Mapping the Effects of Blast and Chemical Fishing in the Sabalana Archipelago, South Sulawesi, Indonesia 1991-2006 A thesis presented to the faculty of the Center for International Studies of Ohio University In partial fulfillment of the requirements for the degree Master of Arts Lauri A. Hlavacs August 2008
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Mapping the Effects of Blast and Chemical Fishing in the Sabalana Archipelago,
South Sulawesi, Indonesia 1991-2006
A thesis presented to
the faculty of
the Center for International Studies of Ohio University
In partial fulfillment
of the requirements for the degree
Master of Arts
Lauri A. Hlavacs
August 2008
2
This thesis titled
Mapping the Effects of Blast and Chemical Fishing in the Sabalana Archipelago,
South Sulawesi, Indonesia, 1991-2006
by
LAURI A. HLAVACS
has been approved for
the Center for International Studies by
Gene Ammarell
Associate Professor of Sociology and Anthropology
Gene Ammarell
Director, Southeast Asian Studies
Daniel Weiner
Executive Director, Center for International Studies
3
ABSTRACT
HLAVACS, LAURI A., M.A., August 2008, Southeast Asian Studies
Mapping the Effects of Blast and Chemical Fishing in the Sabalana Archipelago, South
Sulawesi, Indonesia, 1991-2006 (151 pp.)
Director of Thesis: Gene Ammarell
The overall purpose of this project was to demonstrate the usefulness and cost
effectiveness of Landsat imagery in mapping reef damage resulting from the use of two
destructive fishing practices, blast and chemical fishing. As a side benefit, the protocol
can be used in educational settings where scientists as well as high school and university
students can map these unsustainable activities over large areas.
The living coral reefs of eastern Indonesia are the most diverse in the world, and
they are also among the most threatened by human activity. The long illegal destructive
fishing practices of chemical and blast fishing have been so widely used that many of the
reefs have been damaged to the point of habitat-wide collapse. This project focuses on
the formerly highly productive reefs surrounding a small chain of islands in the Sabalana
Archipelago, a group of islands located roughly half the distance between the main
Indonesian islands of Sulawesi and Sumbawa.
Habitat-scale change was mapped in four change images between 1991 and 2006
using the increase in relative brightness as the habitat shifted from coral-dominated to
algae-dominated and then to dead coral rubble. The output images illustrated how the
damage spread throughout the area as fishermen using destructive fishing practices
progressively exhausted the resources. The destructive fishing effects were differentiated
4 from larger bleaching events in the characteristic that they resulted in a patchy increase in
brightness over the entire reef. Using this image differencing method, Landsat TM and
ETM+ scanners were shown to be useful and extremely cost effective in mapping the
effects of blast and chemical fishing in the study site.
Approved: _____________________________________________________________
Gene Ammarell
Associate Professor of Sociology and Anthropology
5
ACKNOWLEDGMENTS
Many people have been integral in making this project possible. First, I would
like to thank the Center for Southeast Asian Studies at Ohio University and to the
COTIM program in Manado that provided partial funding for the project. Thank you to
the Center for Coral Reef Studies at Hasanuddin University for allowing me to rent the
research equipment. I would like to thank my thesis committee for all their advice in the
research and writing: Gene Ammarell and James K. Lein from Ohio University and M.
Iqbal Djawad from Hasanuddin University in Indonesia. Many thanks to Jamaluddin
Jompa of Hasanuddin University and David Palandro of the University of South Florida
who provided additional input. A special thank you to Edow Maddusila and Gusti
Hardtiny Kemuning from Hasanuddin University who assisted with the data collection in
the field and interpreting. Thank you to Pak Dula and Pak Hamid, the captains of our
intrepid jolor-turned-dive boat and to the family of Pak Supriady for their hospitality and
who continue to run the research station on Balobaloang Island. Thank you to my
professors and to my friends who helped me through the hard times, especially
Pichayalak Pichayakul (Pang), Elizabeth Collins, Joan Kraynanski, Mark and Kanokwan
(Mai) Mason, Farid Muttaqin, Sandra Nahdar, and Muhammad Chozin. And last but not
least a huge thank you to my family, especially to my parents who patiently supported me
through many setbacks and always believed in me. Without you all, this project would
not have been possible.
6
TABLE OF CONTENTS
Page
ABSTRACT........................................................................................................................ 3
ACKNOWLEDGMENTS .................................................................................................. 5
LIST OF TABLES.............................................................................................................. 9
LIST OF FIGURES .......................................................................................................... 10
CHAPTER 1. INTRODUCTION ..................................................................................... 12
CHAPTER 2. DESTRUCTIVE FISHING: CAUSES AND CONSEQUENCES............ 14
2.1 Motivations: Why do Fishermen Use Destructive Fishing Practices? ................... 19
2.2 Chemical Fishing .................................................................................................... 27
2.3 Blast Fishing ........................................................................................................... 31
2.4 Ecological Effects of Destructive Fishing Practices............................................... 36
2.5 Economic Effects of Destructive Fishing Practices................................................ 40
2.6 Social Effects of Destructive Fishing Practices...................................................... 42
CHAPTER 3. BALOBALOANG ISLAND: A VICTIM OF DESTRUCTIVE FISHING
........................................................................................................................................... 44
3.1 Academic Work on the Island ................................................................................ 50
3.2 Getting There .......................................................................................................... 54
3.3 The Island and the People....................................................................................... 56
CHAPTER 4. MARINE APPLICATIONS OF REMOTE SENSING IN MONITORING
REEF DAMAGE FROM BLAST AND CHEMCIAL FISHING.................................... 66
4.1 Obstacles to Current Research................................................................................ 67
7
Problems with Current Coral Reef Status Estimates ................................................ 67
Problems with Reef Status Monitoring ..................................................................... 71
Real and Perceived Cost Effectiveness of Satellite Imagery..................................... 72
The Advantage of the Landsat Archive ..................................................................... 75
4.2 Problems Specific to Remote Sensing in Marine Environments............................ 76
Spatial Resolution Issues .......................................................................................... 77
Atmospheric and Water Column Attenuation ........................................................... 78
4.3 Using Landsat to Assist in Coral Reef Management Efforts.................................. 79
CHAPTER 5. VISUALIZING THE PROBLEM OF DESTRUCTIVE FISHING IN THE
SABALANA ARCHIPELAGO........................................................................................ 83
5.1 Digital Change Detection........................................................................................ 84
Scale of Investigation of a Highly Complex System.................................................. 84
Detecting Coral Death from Space........................................................................... 87
5.2 Project Objectives ................................................................................................... 90
5.3 Methods .................................................................................................................. 92
Image Processing Prior to Field Research............................................................... 93
Field Data Collection ............................................................................................... 96
Image Selection....................................................................................................... 100
Image Differencing ................................................................................................. 101
Registration............................................................................................................. 102
Atmospheric and Water Column Corrections......................................................... 105
Change Detection via Image Differencing of the Blue Band 1............................... 106
8
End User Image Production ................................................................................... 107
5.4 Results and Discussion ......................................................................................... 110
CHAPTER 6. CONCLUSIONS AND RECOMMENDATIONS.................................. 113
6.2 Challenges and Other Things to Take into Account............................................. 117
6.3 Suggestions for Future Work................................................................................ 120
6.4 Follow the Supply Chain ...................................................................................... 123
6.5 Take Advantage of the Free Landsat Archive ...................................................... 124
BIBLIOGRAPHY........................................................................................................... 125
APPENDIX A. RAW DATA USED IN CHAPTER 5................................................... 140
Satellite Imagery Profiles............................................................................................ 140
Locations of GPS Control Points to Register Images................................................. 145
APPENDIX B. RAW TRANSECT DATA.................................................................... 146
APPENDIX C. REEF BALL INFORMATION............................................................. 151
9
LIST OF TABLES
Page
Table 5.1: Comparison of Landsat TM and ETM+ Scanners.........................................86
Table 5.2: Specifications of Imagery Chosen ...............................................................100
Table 5.3: Pixel Values for Change Images..................................................................107
10
LIST OF FIGURES
Page
Figure 2.1: Patterns of diversity in reef-building scleractinian corals ............................15
Figure 2.2a: An outcropping of live coral within a large area of rubble ........................34
Figure 2.2b: Another photo of the same “killing fields” of rubble.................................34
Figure 3.1: Depth chart of the Sabalana Archipelago.....................................................46
Figure 3.2a: Building a lambo on Balobaloang Island, June 2006 .................................49
Figure 3.2b: The lambo we traveled on to the island......................................................49
Figure 3.2c: A smaller fishing boat (jolor) at low tide ...................................................49
Figure 3.3: Balobaloang Island is sighted.......................................................................55
Figure 3.4a: Traditional Bugis style house on Balobaloang Island ................................58
Figure 3.4b: Modern style house on Balobaloang Island ...............................................58
Figure 3.5a: Balobaloang mosque...................................................................................62
Figure 3.5b: Balobaloang elementary school..................................................................62
Figure 3.5a: People walking in the intertidal zone at sunset...........................................65
Figure 3.6b: People walking in the intertidal zone at sunset ..........................................65
Figure 3.6c: A sea cucumber (teripang) caught in a tide pool ........................................65
Figure 3.6d: A sea cucumber (teripang) caught in a tide pool........................................65
Figure 3.6e: A sea urchin caught in a tide pool ..............................................................65
Figure 3.6f: A puffer fish caught in a tide pool ..............................................................65
Figure 4.1: Southeast Asian reefs threatened by destructive fishing ..............................70
Figure 4.2: Location of the study area, Landsat bands 3,2,1 in RGB.............................82
11 Figure 5.1: Reflectance of live vs. dead coral.................................................................90
Figure 5.2a: Isodata classified image of the Sabalana Archipelago ...............................95
Figure 5.2b: Subset of potential dive sites ......................................................................95
Figure 5.2c: The primary field research map..................................................................95
Figure 5.3a: Transect locations of observations, natural color, bands 3,2,1 in RGB .....98
Figure 5.3b: Transect locations of observations, Isodata classified image ....................99
Figure 5.4: Change detection map of reef brightness, 1991-2006................................109
Figure 6.1: Outline of reef zonation..............................................................................114
12
CHAPTER 1. INTRODUCTION
Use of the two destructive fishing practices of blast and chemical fishing has led
to extreme reef damage in the most biologically diverse coral reefs in the world located in
eastern Indonesia. Many areas of the world have developed strategies to protect their
reefs, including national marine parks and marine protected areas. These areas are
frequently so large vast that on site monitoring the effects of blast and chemical fishing is
logistically so difficult that it is nearly impossible. With such large areas to monitor,
satellite imagery is the most suitable strategy to detect the effects of these activities.
Newer satellites that produce imagery with high spectral and spatial resolution are very
expensive, whereas both the Thematic Mapper (TM) scanner aboard the Landsat 5
satellite and the Enhanced Thematic Mapper (ETM+) scanner aboard the Landsat 7
satellite produce imagery that is inexpensive and effective for mapping reef loss.
To demonstrate the usefulness of Landsat’s TM and ETM+ scanners in mapping
reef loss resulting from blast and chemical fishing, this project used five images from
1991, 1992, 1995, 1999, and 2006 in an image differencing change detection technique.
Change images were produced between each of the images and combined in one map
which showed reef loss resulting from blast and chemical fishing. Here change was
defined as an increase in brightness between the years which resulted from the death of
symbiotic zooxanthellae (algae) that lives within the corals and gives color to the
animals. The death of the corals that results specifically from blast and chemical fishing
13 is mapped as patchy increases in brightness, rather than broad increases in brightness as
would be seen in large bleaching events as with temperature increases.
For the description of the data collection and analysis, the reader should turn
directly to Chapter 5. Chapters 2 to 4 are devoted to providing an in-depth background on
the use of the two destructive fishing practices, the study site, and marine remote sensing.
Chapter 2 focuses on the motivations of the fishermen for using destructive fishing
practices in general and the ecological, economic, and social consequences of these
activities. It is important to note that destructive fishing has wide ranging effects and does
not only impact the reefs. Chapter 3 gives an overview of the study site and other
academic work done by researchers from Ohio University in Athens, Ohio and
Hasanuddin University in Makassar, Indonesia. In Chapter 4, the problems with current
reef status estimates and monitoring are covered as well as the usefulness of Landsat in
more accurately mapping coral reefs. The final chapter, Chapter 6, gives some
recommendations for future research specific to the research site as well as for Indonesia
in general. The relevant literature is reviewed throughout the introductory chapters,
Chapters 2 through 5, as the various topics are discussed.
14
CHAPTER 2. DESTRUCTIVE FISHING: CAUSES AND CONSEQUENCES
Reefs embody the mixture of the minute and grand, ephemeral and permanent, simple and complex that we associate with the natural systems of this planet (Hatcher, 1997)
Coral reefs are among the most diverse ecosystems, the underwater analogues to
their terrestrial counterparts, the rainforests. Because the efficiency of coral reefs is based
on “recycling of nutrients, [the] net production is actually very low” making them
“poorly suited to large-scale extractive exploitation” (Roberts, 1995). Tropical fish
experience much higher mortality rates than those in temperate regions. Specialist fish
adapted to specific niches within the reef abundant in the tropics are smaller, requiring
more food, than their temperate counterparts (Pauly, 1994, p. 16-19). The coral reef is an
extremely fragile habitat that is too often taken for granted by humans.
Hallock (1997, p.13) described the term reef as, to seafarers, any “submerged
hazard to navigation” which can include those produced by natural (biological and
geological) processes or artificial processes. Reefs can exist anywhere around the world,
but coral reefs are restricted to within roughly 30 degrees of the equator and are made of
a “rigid skeletal structure in which stony corals are major framework constituents.”
Within this paper, the reefs in question are described in as much detail as possible (e.g.
living coral reefs, dead coral reefs, etc).
15
In the past thirty years there has been much discussion about human activities
impacting the health of these communities. Destructive fishing practices (DFPs) defined
by Pet-Soede and Erdmann (1998) include any activity that “results in direct damage to
either the fished habitat or the primary habitat-structuring organisms in the fished habitat
(e.g. [reef building] scleractinian corals in a coral reef fishery)”; such activities include
chemical and blast fishing, anchor damage, trawl fishing, fishing with fine mesh gill nets,
and “weighted scare lines” (Roberts, 1995). The research within this paper will focus on
the first two methods as those are most relevant to the specific coral reef habitat in the
study site, whereas trawling is more applicable to deep water fishing and not used much
in Indonesia. The reefs around Southeast Asia, and in particular the eastern Indonesian
archipelago, are perhaps the most important areas for DFP research because they have not
only the greatest diversity (an area known as the Coral Triangle) but also the most
destructive of human activities (the darkest purple are in Figure 2.1).
Figure 2.1: Patterns of diversity in reef-building scleractinian corals; the study site is in the area of highest diversity in the world (adapted from Burke et al., 2002, p. 14.)
16
The seas of eastern Indonesia, east of Bali and Borneo (the most eastern islands
before the Wallace Line), are about 20% more diverse than those in the Java Sea in
general, and rare species are much more prevalent. Endemic coral species were found to
make up 25% of the total pool of species sampled. However the variability has dropped,
with now 25% fewer coral genera when compared to those of 1980, and human factors
were suggested to be the reason for the loss (Edinger et al., 2000). The illegal destructive
fishing practices in the region endanger 56% of the region’s reefs (Burke et al., 2002, p.
29), and chemical and blast fishing are more common in parts of eastern Indonesia
(Edinger et al., 2000). These losses are estimated to add to the total loss of the world’s
coral reefs of about 60% by 2030 (Wilkinson, 2000, cited in Spurgeon, 2002).
The coral reef is the home for a wide variety of fish, crustaceans, non-vertebrates,
sea turtles and many other creatures and “are essentially massive deposits of calcium
carbonate that have been produced by corals” (White, 1987, p. 3). Contrary to
misperceptions, corals are not plants. A coral formation is a colony of genetically
identical organisms living together. This organism, referred to as a coral polyp, is related
to jellyfish and can even be thought of as an “upside down” jellyfish, with the stinging
tentacles facing out toward the ocean while searching for food.
What makes the scleractinian (hard, reef-building) corals especially interesting is
that as much as ninety percent of the food it consumes is made from symbiotic
photosynthetic algae called zooxanthellae living within the polyp. So even though the
polyp can consume its food, a large portion is made within (Tomascik et al., 1997, p.
251). In return, the polyp provides the algae with carbon dioxide as a byproduct of its
17 respiration. This mutually beneficial relationship is the basis for study within this paper;
for without the algae, the polyp cannot live and vice versa. The algae and polyps can be
killed by chemical and blast fishing methods, and in shifting from live to dead, a spectral
brightening occurs which can be detected by satellite imagery. (This will be explored
more fully in the data analysis in Chapter 5.) Scleractinian corals are the creatures that
secrete the calcium carbonate to build up the reefs over time and have a distinctive color
when living.
Anthropogenic (human) activities which cause the death of the zooxanthellae such
as pollution or sedimentation (blocking out the sunlight needed for photosynthesis) are
well known in urban areas (Edinger et al., 1998). However in communities which rely on
the reef ecosystem for their food, there are even more destructive activities killing the
coral during the fishing activities themselves, blast and chemical fishing.
To offset such destructive fishing practices and in planning for future
rehabilitation, researchers have pointed to the need for increased monitoring efforts (Tun
et al., 2004). Only a small portion of reefs are protected by marine protected areas
(MPAs), areas where a management group (either governmental, non-governmental, or
co-managed by both) oversee regulation of human activities within the area for the
purposes of conservation and protection of the natural resources through enforcement of
set local policies. MPAs currently cover “18.7% of the world’s coral reef habitats.”
Though over 40 new MPAs have been created each year over the past 10 years, few are
well managed and little enforcement is present. Only 88 of 980 MPAs (covering 1.6% of
reefs worldwide) are well managed so as to prevent poaching, and “management
18 performance . . . is particularly low in areas of high coral diversity such as the Indo-
Pacific and Caribbean.” Harvesting outside the boundaries of the MPAs with limitations
on fishing, called “no take zones”, can still have a negative effect. Overfishing, pollution,
and sedimentation adjacent to the MPAs can all affect fish populations within the
protected areas (Mora et al., 2006).
In the past, laws against illegal destructive fishing practices in Indonesia were
enforced with the backing of the military under the 40-year Soeharto rule. In the 1960s,
trawling was banned after cutting into catches of traditional fishermen. The small-scale
fishermen retaliated against the trawlers, the press became involved, and the government
intervened, limiting trawling grounds along with permit constraints. When the trawlers
ignored the laws by fishing at night, Soeharto banned them all-out and they disappeared
as he called on his navy to enforce his ruling. This “act of intervention” was not
unwelcome by the fishing communities (Berrill, 1997, p. 60-61). Though trawling is not
covered in this study nor were the laws applied in the area, the strong Indonesian
government enforcement of maritime laws in the past stands in stark contrast with the lax
enforcement of the small scale fishermen using DFPs. With the rise of democratization in
the past decade and weakening of the military, laws protecting fisheries are flaunted by
small scale fishermen who are rarely prosecuted. According to one resident of
Balobaloang Island (personal communication), after Soeharto, conflict over territory and
jurisdiction emerged between the three law enforcement organizations, the water police
(POLAIR), the local police (POLRI) and the navy, leading to difficulties enforcing the
DFP laws.
19 Because of the difficulty enforcing the laws, MPA managers and other
organizations interested in protecting the fisheries must be able to monitor the health of
large scale fisheries. The damage created by DFPs need to be monitored both inside and
outside MPAs. Such monitoring at large habitat-scale levels are most appropriate for
satellite imagery techniques, which is the focus of this paper.
2.1 Motivations: Why do Fishermen Use Destructive Fishing Practices?
A number of theories have been put forth by the academic community to explain
the reasons why fishermen in Southeast Asia use methods that are destructive to the very
resources they rely on for their livelihoods. Many of these theories complement each
other and suggest a variety of factors that together provide an explanation of why
fishermen use destructive fishing practices. I argue that no one factor is sufficient unto
itself, but each is a small piece in a comprehensive explanation for the motivation of DFP
use.
Extreme ecosystem-wide overfishing in the Philippines has been described by
scientists working for the International Center for Living and Aquatic Resources
Management (ICLARM) as Malthusian overfishing, the “logical result of declining catch
per effort (and hence income)” (Pauly et al., 1989). In developing countries fishermen are
among the poorest in the economy and have few possibilities for alternative employment.
Sons enter the profession of their fathers and, together young migrants from farming
20 areas, respond to increasing pressure to feed a population growing unchecked. Both
subsistence and commercial fishing operations effectively destroy the entire ecosystem in
trying to catch more fish with progressively fewer fish available. The fishermen are
subsidized by income from the more mobile daughters who move to work in factories in
cities and then send a portion of their incomes to their brothers and fathers who are
fishermen in coastal communities; this subsidization keeps the fishermen working the
seas, where the income would not normally be able to support them, and they continue
fishing the depleting fish stocks (Pauly, 2008).
When faced by declining fish stocks, traditional fishermen who use line and hook
methods are forced to decide to either change profession (if there are any alternatives) or
to switch to destructive fishing techniques if they hope to make a profit from their
catches. In the study site of Balobaloang Island, there are, in fact, alternatives to fishing
such as inter-island trade and coconut silviculture. Those outsiders who choose to fish
using DFPs cause a shift to smaller fish populations, lower fishery productivity, and
eventually total collapse; scholars point to the increase in use of DFPs as the reason for
the ecosystem collapse (Pauly et al., 1989). The intention in coining the phrase
“Malthusian overfishing” was not to directly link population growth with overfishing;
rather, it was intended to emphasize the point that coastal communities should not be
areas of last resort for those who cannot find employment elsewhere and are not areas
that can produce an increasing amount of goods and services (Pauly, 1994, p. 117).
Malthusian overfishing typically involves “growth, recruitment and ecosystem
overfishing as well as a variety of destructive fishing methods” (McManus, 1997).
21 Growth overfishing is where “fish are caught before they [have] ‘had a chance to grow’”
and is common throughout Southeast Asia; recruitment overfishing is where the numbers
of adult fish are diminished by environmental degradation or overfishing so as to leave
few reproductive individuals to replace the population; and ecosystem overfishing is
where the entire ecosystem is altered and previously abundant populations are not
replaced (Pauly et al., 1989; Pauly, 1994, p. 91-93).
A classic example of recruitment overfishing can be seen in the populations of
grouper (genus Epinephelus of the family Serranidae; Indonesian: ikan kerapu) within the
Coral Triangle. Grouper tend to “spawn in large aggregations at traditional sites during
short time periods” during which “fishermen [who are familiar with such behavior] tend
to catch large numbers of fish over such aggregations,” leading to direct removal of the
reproductively active fish “and thus may have severe detrimental effects on future fishery
yields” as the fish can live up to 100 years (Shapiro, 1987, p. 295 and p. 313). According
to local fishermen from the study site of Balobaloang Island, spawning groupers are
known to be “lazy feeders” during this period and are hard to catch using traditional
fishing methods of lines and bait. It is when these spawning populations are targeted
using blast fishing methods that the adult population is damaged, resulting in recruitment
overfishing (Ammarell, personal communication).
Recent market prices for line-caught fish for local consumption at Paotéré Harbor
in Makassar, Indonesia [using the exchange rate of roughly Rp.9,000 to US$1] for the
local varieties of grouper caught for export have been reported to be between Rp.70,000
(US$7.78) and Rp.300,000 (US$33.33) per kilogram, making a large fish a highly
22 profitable catch and as such, a target for chemical fishing (Chozin, personal
communication). Because blast fishing kills the fish, this method cannot be used to catch
fish intended for shipment for consumption abroad, as they are to be held in live tanks for
fresh preparation in the restaurant. Traditionally these fish were not sold for export, but
dried and sold in port for less money; more recently however, increasing demand and
high market prices make the grouper targets for the international live fish trade (The New
Zealand Herald, 1/25/2007).
Because groupers are sedentary creatures that rely on ambush tactics for feeding,
they are “dependent on a hard substrate habitat” and require spatially complex shelters
“in terms of area, relief, and shelter size” (Parrish, 1987, p. 421) which are frequently
destroyed by blast fishing. Particularly susceptible to disturbances in the environment, the
non-territorial, migratory grouper will move on to a new spawning area if the old one has
been damaged (Wilson and Wilson, 1992, p. 97 and p. 152). Researchers have even
found spatial distribution in other areas to roughly correspond “to the distribution of reef
building corals” (Parrish, 1987, p. 422).
Care must be taken however, not to point the finger at in-migration to coastal
areas as being a significant factor in the increase in the destructive fishing. Cassels et al.
(2005) showed that there is no linear relationship between the size of a coastal population
and the health of the local environment, and that there are factors other than migrant
status that affect resource extraction and use. Though there is a relationship between
“migration and lower environmental quality, i.e., large numbers of migrants live in
villages with poor quality coral reefs,” this does not show causality. They could not draw
23 the conclusion that migration “is directly connected with poor environmental quality via
destructive fishing behavior,” where poor migrants “are incorporated into the fishing
sector rather than the subsistence sector” through either economic methods or
intermarriage. There are no behavior differences between migrants and non-migrants in
damage to the environment; when assimilated into the community, there are no
behavioral differences to suggest that “migrants degrade the coastal environments”
(Cassels et al., 2005). Because of the perception that the fishermen are desperately poor,
their destructive fishing methods are seen as a last resort by those who “pity” the
fishermen (Erdmann, 2001). The number of fishermen actually born in the study site
within this paper is currently not known by the author and would be a topic worth
pursuing within the context of the above migration studies. Though there appears to be
no significant migration to the study site, this is an important point to note as possibly
being applicable to other areas within the Coral Triangle.
In an extension of the population pressure theory of Malthusian overfishing, the
motivation to overfish is simply that, as in “Papua New Guinea, blasting is used as an
economically viable fishing method (myopically speaking) in the midst of what are
perceived to be limitlessly abundant coral seas” (McManus, 1997). This is more likely to
be the motivation among Indonesians than in the Philippines where the research for the
Malthusian overfishing theory was done. This opinion of “limitlessly abundant coral
seas” has also been expressed by fishermen using blast fishing in the study site within
this paper and will be explored further in later chapters (Hapsari, 2008). Similarly, in
other areas (including Balobaloang Island) DFP use is motivated by “’greed rather than
24 need’” as with criminal enterprises, and is protected through corruption throughout the
political network (Erdmann et al., 2002; Thorburn, 2003; Hapsari, 2008).
Blast fishing in fact can be very profitable (if the reef has not already been
destroyed). Divers with medium and large scale operations can make around US$50-$150
per week, more than ten times the average Indonesian laborer (Pet-Soede and Erdmann,
1998). Pet-Soede and Erdmann (1998) suggest that the destructive fishing techniques
may be the preferred method and used first because of the high salaries. They cite a study
that shows small-scale fishermen in Asia as actually being much higher in socio-
economic status, having incomes “often equaling or surpassing national averages” (at
least, before the Asian financial crisis) showing greed as much of a motivation as need.
Furthermore, Subani (1972, p. 80) writes that chemical and blast fishing are
preferred because they are easier and quicker for the fishermen to catch fish in a
relatively short period of time when compared to traditional hook and line fishing. Using
explosives, the fisherman does not need to have any specialized knowledge of fisheries or
other experiences with fishery issues, but only needs the knowledge of how to detonate
an explosive. However, Chozin (2008) has shown that among the small crew of about six
on such an operation, there are a variety of skills used such as spotting schools of fish and
knowledge of timing the detonation so as to target that school.
Furthermore, this trend in pursuing DFP use for profit reflects the Malthusian
Tragedy of the Commons thesis according to which “failure occurs where individuals
seek personal benefit in environmental systems and costs are ‘externalized’ to the group”
in areas where there is no organization of the extraction of resources (Robbins, 2004, p.
25 44). In the case of Balobaloang Island (the area of interest in this study), the fishermen
from Sumanga’ Island who use blast fishing say that they give a portion of the catch to
the people of Balobaloang, and so there is some benefit to the group as a whole (though
one or two fish out of a ton is almost nothing) (Hapsari, 2008). The Tragedy of the
Commons can be thought of as an extension of Malthusian overfishing: the fishermen
who have chosen to continue fishing in the face of declining fishery productivity are
under pressure to catch fish with decreasing resources, thereby using DFPs that damage
the commons in a way that affects the larger population with lower yields, while the
fishermen themselves continue to profit.
According to Paul Robbins, author of Political Ecology, there are two big
problems with the Tragedy of the Commons thesis when applied to marine environments.
The first problem with the thesis is that, in focusing on the people, technology, and laws,
it ignores many of complexities of the biological and reproductive processes of the
fisheries. Fish populations are a result of a large number of factors, only one of which is
predation and fishing. The second criticism of the Tragedy of the Commons is that it
operates in an “open-access environment, free of constraints on entry, with no rules to
govern their behavior and catch.” This is rarely the case, as many communities (such as
in the study site in the Sabalana Archipelago) often have informal, unwritten rules by
which the fishermen operate (Robbins, 2004, p. 153-154) as well as formalized rules of
the national and local government of Indonesia.
The idea that greed is fueling the overfishing is further supported by local
officials who, in taking “protection money,” add to this perception; “for the average
26 coastal policeman, a cyanide boat is viewed more as a source of ‘extracurricular
funding’” (Erdmann, 2001). It is not the small fishermen then, who are blamed in such
situations, but the elite Indonesians, companies backing and financing the fishermen, and
even the demand from outside Indonesia.
In 2000, Christopher Johnson of The Globe and Mail (9/5/2000) reported that a
“one-metre Napoleon [wrasse], served alive with an exposed heart . . . fetched CN$3,000
[US$2,040 at the 9/4/00 exchange rate of CN$0.68 to US$1] in Hong Kong.” Eating live
reef fish is “a status symbol for many newly rich Chinese” in Hong Kong, Taiwan, and
mainland China and has caused populations to plummet, according to a 2007 World
Conservation Union (WCU) report. The report found the number of some grouper species
and Napoleon wrasse to fall as much as 99% between 1995 and 2003 (Casey, 1/24/2007).
Most Hong Kong people are reported to prefer grouper caught on a reef to those raised on
fish farms, as “farmed fish is less tasty and fresh”; it is this very demand from China that
has “decimated endangered species in Asia” such as wrasse, grouper, and coral trout,
according to the WCU (The New Zealand Herald, 1/25/2007).
Furthermore, a USAID study that found the “biggest culprit” threatening the
world’s coral reefs to be the United States, in importing 80% of all coral reef products,
and is “the world’s largest consumer of live coral and live rock for the aquarium trade”
(3/3/2000). [Think - Have you ever eaten grouper or seen a saltwater aquarium?] All of
these external factors drive the use of destructive fishing practices (Lowe, 2002).
This brings us back to the idea that indebtedness, or relative poverty, is a factor in
DFP use: fishing companies provide equipment such as motors, and the poor fishermen
27 are forced to use DFPs to pay off the debt from the equipment. The companies also buy
the live catch and pay for the release of the fishermen who are caught and jailed for the
illegal activities. In such cases, it is the fishing companies that run the trade and are
effectively the culprits for motivating and sustaining DFPs. The poverty of the fishermen,
where they cannot pay for the equipment up front, makes them susceptible to financing
schemes and to the pressure from companies to have a large catch from diminishing
resources. For example, people of the Togean Islands of North Sulawesi “do believe that
cyanide is harmful, but feel helpless to oppose it” (Lowe, 2002).
All of the factors listed above contribute to the use of DFPs: population growth,
choice to continue fishing in the face of dwindling resources, greed of fishermen and
companies, corruption of local officials, increased demand from abroad, and indebtedness
(relative poverty). When taken together, all of the above factors provide a comprehensive
explanation of why fishermen resort to using destructive fishing practices, destroying the
resources they rely on for their livelihoods.
2.2 Chemical Fishing
Chemical fishing (Indonesian: membius) is often used to stun fish so they can be
caught and used both domestically and internationally in the live fish trade of exotic
species such as lobsters (often sold to international tourists in Balinese hotels and
restaurants), groupers, and Napoleon wrasse. Most creatures caught this way are sent
28 overseas for consumption or for saltwater ornamental aquarium fish collectors (Pet,
1997). Two different chemical methods have been used in Indonesia, one using ground-
up plants and the other with cyanide. Cyanide exposure is estimated to unintentionally
kill about 50% of fish exposed on the reef and, of those that survive for transport to Asian
restaurants and aquarium collectors abroad, the subsequent death of about 40% of the
remaining (Sumuch and Morrissey, 2004). Though harmful to the fish, exposure to the
chemicals is deadly for the coral polyps, causing them to expel the symbiotic algae and
lose their color. The bleaching is a “generalized response shown by corals to stress” and
happens in response to a wide variety of extremes such as “temperature, salinity, and
light irradiance” (Brown, 1997, p. 365).
In one method of chemical fishing, poisonous plants (Indonesian: tuba) have been
used, such as kayu tuba (English: tuba wood, or in Latin: Derris elliptica Benth) -- a vine
that can grow to 15 m, with a thickness of 20 mm, and is found in forests along the edges
of rivers, coiling around other plants like the slingerplant. The roots are crushed and
when mixed with water will cause fish to become sick and finally die. Tuba laut (English:
sea tuba, or in Latin: Derris heterophylla Backer) can include many types of bushes
growing along the coast, rivers and marshes. The branches and leaves, when crushed, can
be used to poison fish with a little milder effect, though still killing the fish. Places where
these are used include bays and rivers where the current is not strong and other similar
places such as ponds, lakes, and marshes. When a strong current is present, the poison
can quickly spread far. After the poison is thrown into the water, it kills the fish, which
then float to the surface to be easily collected. Tuba is known in almost every fishery in
29 Indonesia, in coastal communities as well as those inland, according to Subani (1972, p.
78). It has also been observed by Alcala (2000) in shallow coastal areas of the
Philippines. Both are in the genus Derris, in the pea family Fabaceae, the roots of which
contain a chemical used in pesticides, Rotenone (Starr et al., 1999, p. 3).
Tuba is reported to have been used in Komodo National Park, with as many as
60% of fishermen reporting its use “every now and then.” The tuba is reported to be
tossed on top of the water, stunning the fish, not killing them. Different plants are also
reported to be used there; the seeds of Croton argyratus, Croton tiglium, and Anamirta
cocculus are ground and mixed with water, as with Derris (the species were only
reported, but not confirmed by Pet). In the study, fishermen also referred to herbicides
and pesticides used for collecting small groupers, snappers, and emperors as “tuba”,
leading to confusion in interviews. The herbicides are mixed with sand, dumped onto reef
flats and crests, and is reported to be active for three days, killing everything underneath
and everything that passes over the mixture (Pet, 1997).
The other, more common, method of chemical fishing (though presumably more
expensive) is to use plant fertilizer or a tablet of potassium cyanide (KCN) or sodium
cyanide (NaCN) mixed with water and referred to as just “cyanide” (Indonesian:
sianida). The preferred use is thought to depend on availability or price. Because many
authors researching chemical fishing do not specify the type, price, size, how many
tablets per kilogram, it is difficult to know the reasons for choice, and McAllister et al.
(1999) point to Ocean Voice International’s recommendation for these details to be
included in reports, when possible. The use of cyanide began in the Philippines as early
30 as 1962 (and possibly even as far back as 1954 in Taiwan) and quickly spread to
Indonesia (McAllister et al., 1999). These days, in some communities the cyanide is
supplied directly to the fishermen for free by live fish businesses, the companies
mentioned earlier that provide the motivation and sustain the DFPs. Even the Indonesian
army has been accused of facilitating the “circulation of cyanide between the mining
industry and the live fish trade” (Lowe, 2002).
The cyanide is used by breaking a tablet, sometimes by mouth, and mixing with
water in a plastic squeeze bottle (usually one 13 g tablet per liter of water) (Pet, 1997) or
tying the tablet to the end of a pole and waving it “around coral heads or [poking] into
crevices” (McAllister et al., 1999). This is believed to be the most common method of
chemical fishing and accounts for about 70% of the fish caught for the aquarium
industry” as well as those caught for consumption (McManus et al., 1997). The fishermen
can get in close to the fish, which will corner itself inside a coral formation, and squirt it.
A typical fishing trip using chemicals to catch aquarium fish is about two weeks, visiting
four locations, each of which is worked for about three days. Though some do not revisit
locations, others have been known to use a location for several weeks or even months at a
time. Former divers reported working at depths of 10 m-20 m (Pet, 1997).
A third method of chemical fishing, used for catching “consumption fish”,
reported in and around Komodo National Park by Pet (1997) is to mix chopped up bits of
fish mixed with cyanide to catch fish which die after eating the chum. This method
differs from the other uses of cyanide in that it actually kills the fish and, though not
reported or investigated, raises serious questions about the health effects on those eating
31 the fish caught with this method. In the summer of 2007, the Chinese central government
“banned imports of Indonesian fish and other foods after scores of shipments were found
to contain toxic substances,” announcing the ban after “excessive drug residue, additives
and harmful bacteria were found in 121 batches . . . in the first six months” of 2007.
Chemicals found included mercury, chromium, antibacterial drugs, and harmful bacteria.
Within the same article, the reporter found one restaurant manager on Lamma Island who
said, “’We stopped buying fish imported from Indonesia 10 years ago because some
Indonesian fishermen use destructive fishing techniques such as putting drugs in the
water” (Heron, 8/5/2007).
The problem with both tuba and cyanide chemical fishing methods is that, while
stunning the fish, the delicate coral polyps that build the reefs are killed in both the
immediate area and down current, resulting in a one to two meter patch (larger if a strong
current is present) of bleached, dead coral (McManus, 1997). Coral mortality from direct
exposure to cyanide is estimated to be at 5% of corals per year, much lower than that of
blast fishing at 14% per year (seen in an area of the Philippines), confirmed with informal
interviews of fishermen familiar with the practice (McManus et al., 1997).
2.3 Blast Fishing
The second DFP method common in eastern Indonesia is blast fishing
(Indonesian: membom), also called dynamite or bomb fishing. After schooling fish are
32 located visually by the fishermen, the boat moves in close and a bomb is thrown into the
middle of the school. Fish killed from the blast that do not float to the surface must be
retrieved by divers who hold their breaths by free diving or use crude “hookah”
compressors on the boat with an air hose for the divers (McManus, 1997; Pet-Soede and
Erdmann, 1998; Fox and Erdmann, 2000). Blast fishing results in extremely high yields
for the fisherman though the long term effects can be described as a “boom and bust”
affecting the entire fishery (Berrill, 1997). Over time, the bomb composition has changed
from dynamite obtained from Japanese military and construction activities in the early
days to homemade kerosene and fertilizer bombs more common these days (Pet-Soede
and Erdmann, 1998). Apparently a few corrupt Indonesian military members still feed the
demand; in October 2006, the wife of an Indonesian marine was arrested with 9 kg of
TNT and several detonators. She claimed that the explosives, powerful enough to blow
up a two story building, were meant for blast fishing, as her husband had been selling
such items to fishermen in Pasuruan, East Java for the previous six months (Osman,
10/6/2006).
Blast fishing destroys the coral skeletons made of calcium carbonate, and though
some fragments may survive, most die within several months. Corals are killed through
the concussion force which turns the limestone foundations into rubble, with pieces no
bigger than fifteen centimeters in length and a few centimeters in diameter (personal
observation); a bomb of only 1 kg “can leave a crater of rubble 1-2 m in diameter” (Fox
et al., 2003). Repeated bombing over time turns the reef into nothing more than “shifting
fields of dead coral rubble” covering the sea floor that are “punctuated by the occasional
33 massive coral head” (Pet-Soede and Erdmann, 1998; personal observation). It becomes
impossible for new growth to occur because of the instability of the rubble, being pushed
around in the current like garbage, forming “’killing fields’ for coral juveniles” and for
any recruits (new growth polyps) that may be present (Fox and Erdmann, 2000; Fox et
al., 2003; personal observation, see Figure 2.2 below). Furthermore, the destruction of
spatially complex reef structures makes it impossible for fish to use the reef for protection
and hiding; this is the case with juvenile groupers which “settle where hiding places are
abundant” and “hide almost constantly” until they grow to a few inches and can venture
into deeper waters (PT Kedamaian Makmur Sejahtera Grouper Fish Farms).
Areas heavily dynamited undergo a shift from hard coral domination to soft coral,
macroalgae domination and eutrophication (excessive plant growth and decay), though
only in cases where the environment is optimal. Factors affecting suitability for soft coral
growth include “grazing intensity, sedimentation rate, larval ability and survival, and . . .
ocean current patterns” (Fox et al., 2003).
Rubble fields around Komodo National Park in Indonesia estimated to be several
decades old have been found to have “high substrate instability and low survival of
recruits resulting in new coral growth to be “very slow at best, and at worst, nonexistent”,
even with the presence of source larvae necessary for new growth (Fox et al., 2003).
The rubble, which cannot support new growth, must be replaced with a stable
substrate for any kind of new hard coral growth to happen. Coral recruitment (new
growth) is greatly enhanced with a stable substrate that is at a height above rubble so as
to prevent being buried; rehabilitation may be as easy as building “spatially complex”
34 rock piles or introducing cement slabs (Fox et al., 2005). Such efforts have been
undertaken in the area of interest in this study and will be alluded to later.
Figure 2.2: (a) An outcropping of live coral within a large area of rubble, and (b) another photo of the same “killing fields” of rubble. The area is located in a high current area off the western end of Balobaloang Island. Both photos have been edited to show the difference between sand and rubble, which is much brighter in reality (photo by Edow Maddusila, edited by author using Microsoft Photo Editor).
According to a 1972 Marine Fisheries Research Institute in Jakarta (Subani, 1972,
p. 79), blast fishing had only really begun after WWII in Indonesia, and it became more
widespread after the 1950s. When the war had just finished, many of those who had
responsibility dispose of the firearms, grenades, and ammunition did not do so. Not only
did Indonesians use the explosives, but so did their neighbors in the Philippines,
Thailand, and Malaysia. The general public (civilians as well as military) were informed
that using these explosive materials to fish was prohibited, although many people chose
to break the law.
35
In fact, prohibitions against using explosives in fishing had been law since the
time of the Dutch colonial period when the government wrote an ordinance to protect fish
populations. Outlawing the activity suggests that destructive fishing practices had begun
even before WWII, but it was the Japanese soldiers that introduced fish bombing on a
large scale. According to the Dutch regulation, it was forbidden to catch fish using the
following methods: i. materials that contain fish poison (ratjun in the text, or racun in
contemporary Indonesian), ii. materials that cause “drunkenness” or “dizziness” (mabok
in the text, or mabuk in contemporary Indonesian), or near death, and iii. materials that
contain explosives (old and contemporary Indonesian: bahan peledak) (Subani, 1972, p.
81). These days, though illegal, blast fishing is known throughout Indonesia. Though
corruption is thought to keep bombers safe, a number of them were arrested in 1996 in
Komodo National Park, and one of the most important blast fishermen was killed as he
tried to throw a bomb at a patrol boat (Pet, 1997).
Yields from blast fishing are extremely high. Collecting greater than 95% of the
fish killed by two blasts using a kerosene-fertilizer bomb in a 300 mL glass bottle, Fox
and Erdmann (2000) counted 2,153 individuals weighing a total of 75.3 kg. Less than 2%
floated in the first blast thrown into a targeted school of fish. From this catch, each
fisherman made UD$8.35, more than five times the daily Indonesian salary. In the second
blast, thrown randomly on a 10 m deep reef slope, only 10.9 kg of fish was collected,
yielding US$3.83 per fisherman. Less than 20% of the fish collected had no value. Blast
fishing can be profitable, but is more often wasteful, with fish killed that have no value
and many left on the sea bottom (Fox and Erdmann, 2000). Depending on the size of the
36 operation, a typical bombing trip is a week at sea, catching 500 kg to 1,000 kg of fish
which is then dried. Boats without compressors work at depths up to 10 m, and those with
the equipment may work in waters deeper than 5-10 m (Pet, 1997).
Though not included in destructive fishing, coral loss from anchor damage is also
a problem throughout Southeast Asia. Many anchors in the shape of grapple hooks are
thrown into the water and dragged until catching, damaging coral in the process
(McManus et al., 1997; Edinger et al., 1998). The effect is similar to that of blast fishing,
damaging the reefs. However, fishermen of Balobaloang Island in the study site have said
that they prefer sandy areas because anchors can get caught in the coral and are very
difficult to dislodge (Ammarell, personal communication).
2.4 Ecological Effects of Destructive Fishing Practices
In a comparison of the two destructive fishing methods chemical and blast
fishing, Pet-Soede and Erdmann (1998) observed that chemical fishers in Indonesia are
“quite sparing in their use of cyanide” so that “one bout of cyanide fishing on a reef kills
far fewer corals than blast fishing. McManus et al. (1997) also stated that, because of the
higher rate of coral mortality and increased inhibition to regrowth from the destruction of
the structure itself, blast fishing is significantly more destructive than chemical fishing.
This point is still debated however, because of anecdotal evidence pointing to the use of
chemical fishing in earnest in South Sulawesi (Ammarell, personal communication). In
37 the study area within this paper, chemical fishing is reported to be a relatively recent
phenomenon, the use becoming known in 2003 (reported by a resident of Balobaloang
Island, personal communication).
In his research in the Spermonde Archipelago in South Sulawesi roughly 200 km
north of the study site of this paper, Chozin (2008) found that fish captured during blast
fishing operations and later sold at market included mackerel, yellowtail, sailfish, scad,
trevally, sardines, anchovies, snapper, and triggerfish. The ecological impacts of blast
fishing are really an example of what has been happening around the world in developing
countries since the early 1990s. In Komodo National Park, the number of bombing
incidents was found to have tripled between 1991 and 1993, peaking at around 300
incidents annually; biannual peaks were seen in April and in October, the periods
between monsoons when the winds diminished (Pet, 1997).
It is clear that in blast fishing both the blast and concussive force of the
shockwave kills adult fish, fish fry, eggs, and other animals in the area of the blast.
Explosives cause external and internal damage to fish seen in torn fins, swim bladder
damage, broken bones (including related blood loss), damaged eggs, and damaged scales.
In fact, it is the internal injuries characteristic to blast fishing that were frequently used to
prosecute fishermen using this DFP method in Guam; these prosecutions and hefty
punishments eventually led to the practice being stopped in that area (according to an
ICRS conference attendee, personal communication). Additionally, the coral that serves
as fish nests are destroyed by the blast, and the damage to the reef structure itself means
that it will take a long time for the reef to recover from nothing (Subani, 1972, p. 80-81).
38
Another ecological effect of all destructive fishing practices includes the
documented loss of “keystone” species which, though some may not be economical or
the targets of fishermen for consumption fishing, they normally keep others in check.
Such species include triggerfish, pufferfish and other species that are easily killed by
blast fishing techniques (for consumption, as by-catches, or for tourist trade). These fish
have been found to have dropped in population from overfishing from DFP use.
The removal of fish that prey on sea urchins and crown of thorn starfish results in
an explosion of these reef-damaging populations which contribute to the corrosion of the
“reef framework” itself. The reef is changed into an “entirely new type of ecosystem
[where the] habitat is no longer suitable for many of the fish that once inhabited it” (The
Economist, 11/4/2000). Thus, with the disappearance of sea urchin predators and scraping
herbivores, the delicate balance of the reef ecosystem is disrupted. Such events have been
documented in the Red Sea, Kenya, and the Caribbean.
Herbivorous fish are usually caught using blast fishing and are rarely caught with
line and bait. By removing populations of parrotfish, macroalgae can grow out of control
and unchecked, can overgrow corals quickly (Sumich and Morrissey, 2004, p. 266). A
phase shift is seen where the “coral/invertebrate dominated” reef changes to an “algal
dominated” reef community and the removal of keystone species (Pet-Soede and
Erdmann, 1998).
Fishing in general, even at low intensity, has an impact on fish abundance and
diversity; adults of the species are virtually eliminated, “removing all but the smallest
individuals” that are unable to replace the fish population. The loss of adult fish is seen
39 when juveniles begin accounting for “a substantial percentage of the catch” as seen in
1998 in the Riau Archipelago (Pet-Soede and Erdmann, 1998). Storms and eutrophication
exacerbate the problem, making it even more difficult for the reefs to recover from the
overfishing (Roberts, 1995). In North America, overfishing has caused a vast decline in
fish populations forcing the United States and Canada to close fishing grounds in the
Grand Banks and Georges Bank, respectively (Berrill, 1997, p. 2).
Species removal effects resulting from overfishing have been recorded on the
Great Barrier Reef and elsewhere with the outbreak of the reef-damaging crown-of-
thorns starfish (COT) that devour the corals. These outbreaks are thought to have directly
resulted from overfishing, causing the removal of COT predators (Roberts, 1995). COT
outbreaks have also been seen in North Sulawesi and Okinawa (personal observation).
Likewise, through chemical fishing, the removal of grouper which have “often
been characterized as generalized, opportunistic carnivores” that “exert a major predation
pressure on many benthic fishes [those that live on the sea bottom] and invertebrates” can
be expected to reduce predation pressure and potential catches of other demersal [those
that live at or near the sea bottom], carnivorous fishes” (Parrish, 1987, p. 406-408).
Populations of fish species that prey on other fish (piscivores) such as groupers
have seen a massive reduction through overfishing as well. Though because of the
redundancy of species, where “a number of species occupy a similar functional role
within an ecosystem,” animals considered “opportunistic predators” fill the reef. Thus,
the loss of a piscivore population has a much smaller effect on the food web because
“apparent specialists may switch to feeding on the former prey of species [removed] by
40 fishing.” Though a variety of species may all prey on urchins, for example, they all tend
to be caught by the “nonselective” nature of blast fishing (Roberts, 1995).
2.5 Economic Effects of Destructive Fishing Practices
“Boom and bust” describes the process of exploiting a habitat beyond its
regenerative capacity. The “cycle of discovery, exploitation, depletion, and collapse”
defines the history of fisheries where the smaller-scale fishermen may choose to
compensate for smaller catches by using more destructive methods if they wish to
continue being fishermen. Less successful (smaller) fishing operations lose money and
are forced out of the industry. In the final stage of collapse, the fishery is often closed to
fishing in “hopes that it will recover” (Berrill, 1997, p. 4). The fisheries around the area
of interest in this study were fished sustainably for many generations, are now
somewhere between depletion and collapse, most likely closer to collapse than not.
Recently, a small area with still-healthy coral has been closed to fishing, though
enforcing this is highly difficult.
In a study conducted in the Spermonde Archipelago, South Sulawesi, it was
calculated that after the first twenty years of blast fishing “in areas with a high value of
coral reefs for tourism and coastal protection the net loss to society” was the equivalent
of US$306,800/km2 coral reef in tourist areas and the “economic costs to society were
four times higher than the net private benefit to blast fishers”; these numbers are
41 conservative because many non-quantifiable factors were not taken into account.
However for the fishermen using blast fishing it is a profitable venture; in Tanzania the
catch from two days was reported to be the same amount as that which traditional
fishermen caught in twenty days (Pet-Soede et al., 1999).
Chozin (personal communication) reported the market price at Paotéré Harbor in
Makassar for selected fish sold as the following: Rp.3,000/kg (US$0.33/kg) for
anchovies, Rp.3,000~ Rp.5,000/kg (US$0.33-$0.56/kg) for sardines, Rp.5,000
(UD$0.56/kg) for mackerel, Rp.12,000 (US$1.33/kg) for red snapper, Rp.10,000~
Rp.15,000 (US$1.11-1.67/kg) for trevally, Rp.25,000 (US$2.78/kg) for tuna, and for
comparison, between Rp.70,000 ~ Rp.120,000/kg (UD$7.78-$13.33/kg) for lobster,
depending on the season. All of the above were caught using blast fishing except for the
lobster which was caught using chemical fishing and tuna which was caught with hook
and line.
As reported by Osman in The Straits Times of Singapore (10/6/2006)
mentioned earlier, the wife of an Indonesian marine sergeant was arrested trying to sell
9kg of TNT for Rp.3,000,000 (US$333). A police spokeswoman said that she “would be
charged under a 1951 emergency law for carrying weapons and explosives” which carries
the death penalty. Thus the economics of blast fishing is profitable for all involved in the
illegal supply chain, though execution is a potential down side to the trade, if caught.
In destroying the fish populations, those whose businesses rely on the fishermen
also experience decline. Shipbuilders, makers of nets and other fishing tools, salt
42 businesses, and transportation all suffer (Subani, 1972, p. 80). Blast fishing becomes less
cost effective as fish population densities in target areas decline (McManus et al., 1997).
2.6 Social Effects of Destructive Fishing Practices
Even though it makes it easier and quicker to catch a large number of fish, blast
fishing is actually full of dangers, such as severed limbs, deafness, and blindness. Many
continue the practice because of the high income potential, with few victims, and get
good results in a brief period (Subani, 1972, p. 80). Bombs assembled at home and stored
under houses are extremely dangerous for the whole family and are often constructed by
men, women, and children. The “return on investment is considered high enough” to
offset the danger and make the risk worth taking (McManus et al., 1997), although in
interviews with fishermen using blast fishing, Chozin (2008) found that many believe
that their fate is determined by god and that decisions to use this DFP is less of a material
cost/benefit analysis.
The effects of blast fishing can be seen in other areas of Indonesian society as
well. In August 2007 a large blast occurred in the coastal village of Pasuruan, a coastal
town about 70 km east of Surabaya in the province of East Java. This is the same area
where the wife of an Indonesian military man had been arrested less than a year earlier
selling TNT that had been obtained from the Indonesian military. The blast “ripped
through several houses” and killed three people. After investigation by special terrorist
43 task force, the case was reported to have been a result of a man improperly mixing
explosives to be used in blast fishing. Body parts were found as far as 40 m away from
the blast, and 10 kg of TNT (later reported by the AFP to be 79 kg) and 934 detonators
were found in the ruins by police (The Sydney Morning Herald, 8/11/2007;
Boediwardhana, 8/13/2007; Agence France Presse, 8/18/2007; People’s Daily Online,
8/22/2007; Harsaputra, 8/22/2007).
In both chemical and blast fishing, divers must collect the dead fish that fall to the
seafloor. Frequently the “crude hookah equipment” (usually a tire compressor) which
delivers the diver unfiltered air can cause serious injury from “decompression sickness,
embolisms, hearing loss, and other diving related maladies” (McManus et al., 1997).
Chozin (personal communication) reported divers going as deep as 40 m (10 m deeper
than recreational no-decompression SCUBA diving limits) because the shallower areas
had been destroyed. Inhaling air mixed with oil is frequently seen in people who are not
trained to understand the technicalities involved in decompression diving, leaving many
widows in the fishing industry (Alcala, 2000).
When a fishery is overexploited, the people who rely on the fish as their
livelihoods are forced to move to other areas, usually cities where they would rather not
be, in order to learn new jobs (Berrill, 1997, p. 3). The people who look to make their
livelihoods from fishing will quickly run into the business decline mentioned above and
will also experience financial loss because the fisheries will continue to suffer from
nobody taking responsibility for their destruction (Subani, 1972, p. 80).
44 CHAPTER 3. BALOBALOANG ISLAND: A VICTIM OF DESTRUCTIVE FISHING
Over the past twenty years, faculty and students from Ohio University (OU) have
been conducting a variety of research activities on and around Balobaloang Island; this
research will frequently be referred to within this project as it is represents a
comprehensive collection of research written about an area within Southeast Asia with
regards to destructive fishing methods and the effects caused. Throughout this paper,
contemporary Indonesian names will be provided in italics, where appropriate.
Greater Balobaloang Island (Pulau Balobaloang Besar – “P. Balobaloang Br.”
on the navigational/depth chart in Figure 3.1 below) is on the northwestern end of the
diminutive Sabalana Archipelago (Kepulauan Sabalana), roughly half way between the
much larger main Indonesian islands of Sulawesi to the north and Sumbawa to the south.
The archipelago is about 200 km from both, and in the southern part of the Strait of
Makassar on the edge of the Flores Sea.
It is the location of the archipelago itself which makes this island group excellent
for a study using satellite imagery. Being so far from urban areas, the islands of the
Sabalana Archipelago are free from chronic land-based stressors such as 1. sewage
pollution, 2. air pollution caused by factories and automobiles, and 3. siltation caused by
deforestation, agricultural, and construction runoff (Edinger et al, 1998) - human factors
that complicate satellite monitoring of reefs close to large urban areas. However,
chemical and blast fishing methods are more prominent in areas that are further from
45 major urban areas (Edinger et al., 1998) such as the Sabalana Archipelago because lower
population densities lead to a lower possibility of being caught by police and provide
clearer waters for fishing (Pet-Soede and Erdmann, 1998). Furthermore, the islands are
outside the cyclone belt and rarely subject to the major storm damage that destroys
Caribbean reefs. They also experience upwellings which protect the area from warm
water of the El Niño Southern Oscillation bleaching events such as that of 1998 (Fox et
al., 2005).
Composed of almost twenty small islands, the largest of which can be
circumnavigated by foot in less than two hours, the Sabalana Archipelago is roughly 45
kilometers wide by 45 kilometers long. Geographically, the islands run from northwest to
southeast in the shape reminiscent of a saxophone, and there is a shallow flat of 20
kilometers by 8 km (narrowing to 4 km) on the southeastern end. Each of the small
islands is surrounded by a fringing reef, and there are two large areas on the western side
of the archipelago composed of submerged reefs (Indonesian: taka) between 8 to 20
meters in depth used as the main fishing grounds. The open water to the south and west
of the islands is relatively shallow, with depths outside the taka about 55 m (30 fathoms).
On the eastern and southeastern side of the island group, the reefs steeply drop off to a
depth of more than 546 m (300 fathoms), with the deepest area being as deep as 3089 m
(1697 fathoms) roughly 50 km to the southeast of the archipelago (Ammarell, 1999, Map
2.3; see Figure 3.1 below).
46
(a)
(b) Figure 3.1: (a) Top: Navigational chart of the Sabalana Archipelago, depths shown in fathoms (image adapted from W.L.J Wharton, Navigational Chart of the Strait of Macassar, Southern Part, 1981; cited in Ammarell, 1999, Map 2.3). (b) Bottom: Location of the study site.
Depth Chart of the Sabalana ArchipelagoDepth Chart of the Sabalana Archipelago(depths shown in fathoms)(depths shown in fathoms)
47
Located roughly 11 kilometers and two islands away, to the southeast of
Balobaloang Island, is Sumanga’ Island (Pulau Sumanga’). In fact, Sumanga’ Island is
administratively part of the Village of Balobaloang (Desa Baloabaloang), along with the
Island of Lesser Balobaloang (Pulau Balobaloang Kecil – “P. Balobaloang Kcl.” on the
navigational chart, Figure 3.1 above) located between the Balobaloang Island and
Sumanga’ Island. Two other distant islands, Pelokang and Longko Itang are also included
in the village unit (Ammarell, 1999, p. 31), though they are so distant as to not be
relevant to this study. Though part of the same village unit, the economies of the two
islands of Balobaloang and Sumanga’ could not be more different. Where the people of
Balobaloang are traders, the wealthier families of the island owning and operating the
traditional Bugis sailing ships called lambo that are used for long distance inter-island
trade, the people of Sumanga’ are mostly commercial fishermen, and as such many have
adopted blast fishing as a reliable method to quickly harvest many fish. Though the
people of Balobaloang do fish themselves for subsistence and some commercial
purposes, they do not fish at the large scale as those from Sumanga’ do, nor do they
currently use the two destructive fishing practices described in this paper.
The people of Sumanga’ who use the blast fishing method do not use the chemical
fishing method; in Hapsari’s video (2008), it is reported that the people of Lae Lae
Island, near Makassar (also known as Ujung Pandang) are the ones responsible for the
chemical fishing in the Sabalana Archipelago. In fact, there is a home reef system around
Lae Lae Island, but it has been destroyed. In their discussion of the nature of the fishers
48 and their ethnic backgrounds, Pet-Soede & Erdmann (1998) noted that it is the mobile
culture of the traditional fishermen “not bound to a ‘home’ reef system” that never forces
them to “deal with the destruction they bring to bear.” They “simply move on” as the
reefs become unproductive. The large cyanide operations of the Spermonde Archipelago
off the west coast of South Sulawesi, near Makassar, had to travel further to acquire the
catch size to meet demand for grouper that greatly exceeded supply (Pet-Soede and
Erdmann, 1998), and perhaps were part of the operations seen in the Sabalana
Archipelago noted by the people in Hapsari’s video.
49
Figure 3.2: (a) top left: Building a lambo on Balobaloang Island, June 2006, (b) top right: the lambo we traveled on (photo by Edow Maddusila), (c) bottom: a smaller motorized fishing boat (Indonesian: jolor) at low tide, a common sight in the afternoon. This particular boat doubled as our dive boat (photo by Edow Maddusila)
Complicating the problem even more is that, while the village head (Kepala
Desa) lives on Balobaloang, Sumanga’ is headed by a lower level official (Sekretaris
Desa or Sekdes for short) who is under the authority of the Kepala Desa. Many of the
bombers from Sumanga’ Island are also related to the people of Balobaloang Island
(a) (b)
(c)
50 through inter-marriage (Hapsari, 2008), though the people of Balobaloang are of Bugis
ethnicity and the people of Sumanga’ are mostly ethnically Makassar.
As with the rest of Southeast Asia mentioned earlier, blast fishing was reported to
have begun around Sumanga’ Island as far back as just after the Japanese occupation,
when they left explosives behind in their retreat in 1945. Those explosives were quickly
used for fishing, though the method was not reported to have started in earnest until the
1990s. Because of a solidarity amongst those who deal in an illegal trade, the people of
Sumanga’ who use illegal blast fishing have allowed the cyanide fishermen from islands
closer to Makassar to use the harbor on their island as a base to practice their trade
(according to a resident of Balobaloang Island, personal communication). The island has
been described to be a den of corruption where all those involved in illegal activities find
security together such as fishermen, police officers, military personnel, and all others “on
the take” (Ammarell, personal communication).
3.1 Academic Work on the Island
In 2002 a memorandum of understanding (MOU) was signed between OU and
Hasanuddin University (UNHAS) in Makassar, South Sulawesi. This partnership allowed
faculty and students from the Center for Coral Reef Studies (CCRS) of UNHAS and the
Center for Southeast Asian Studies (CSEAS) of OU to collaborate on a series of
multidisciplinary projects “to promote a general scientific co-operation of both
51 institutions, covering research, education and training in the fields of integrated coastal
and marine management.” This MOU covered a period of five years and expired in
December of 2007; however, it is due to be renewed by officials from both schools in the
summer of 2008.
With the help of residents of Balobaloang Island, a permanent research station
was built on north side of the island in 2003-2004. Cared for by the family of Supriady,
the principal at the elementary school on the island, the research station has the potential
to be a resource for both scholars and islanders for cultural exchange as well as academic
endeavors. Thus Balobalong Island has become a regional center for research on
destructive fishing practices.
Since 1988, Gene Ammarell, an anthropologist with OU, has been researching the
navigation methods of the Bugis, famous for their long history of seafaring skills.
Throughout the 1990s while doing his own research on Balobaloang, the frequency of
blast fishing increased dramatically. In recent years, interest in learning about the effects
caused by a decade of near-daily blasting has sparked research on the topic within the
area. Ammarell’s personal contacts with the islanders and faculty at UNHAS have made
it possible for OU graduate students to conduct research on a variety academic topics
relating to blast fishing in the area, and he is in the process of describing the fisheries of
the surrounding waters and cataloguing Bugis names for the fish which inhabit the reefs
around the island, among other local projects.
In 2000 Jordan Crago found that the fishermen of Barang Lompo Island near
Makassar were aware of conservation practices in the area but were just not interested in
52 taking part in these practices to preserve the reef because of their distrust of outsiders and
urge to stay out of local politics (Crago, 2001). In 2003 Rita Steyn, a MS student in the
biology program at OU, investigated the depth at which the effects of blast fishing were
greatest. Following Steyn, Amelia Hapsari, a MA student in OU’s Center for Southeast
Asian Studies, produced a video (2008) with a grant from the CSEAS documenting
fishermen in the act of using explosives. Though initiated by Hapsari, an Indonesian from
Semarang on Java, the production and development of the video was in actuality a
“participatory project where the subjects [became] the producers.” Her project followed
the theoretical framework where the victims are empowered through the process of
reflecting on the story as they decide about whom it is told and can then take action on
their oppression (Hapsari, 2008).
Most recently another Indonesian OU MA student from Java in the CSEAS
program, Muhammad Chozin, traveled to South Sulawesi in 2007 to conduct an
ethnographic and social economic study on fishermen who use blast fishing, their
methods, and their religious beliefs in relation to the environment, in an area closer to
Makassar, the Spermonde Archipelago (this is also the island group which includes Lae
Lae Island, mentioned earlier). During his research he also traveled to Balobaloang Island
and Sumanga’ Island (Chozin, 2008). It has been Hapsari’s video, however, which was
the major impetus for my project.
Of greatest relevance to the project within this paper is the portion of the film
when the Vice Village Head, Rewa, took Hapsari onto one of the bombing boats that had
come to Balobaloang, and she interviewed one of the fishermen about their activities. His
53 identity concealed by a ski mask, the fisherman replied that it is “impossible” the ocean
will “run out of fish”; there will “always be fish” as long as the “ocean cannot be dried
out” and that “only a part of the reef will be destroyed. Not all.” When asked, “why do
you bomb here [in Balobaloang], not near your own island of Sumanga’?” the man,
probably in his mid-20s replied, laughing, “there’s no fish there anymore . . . There are
fish there, but only small ones. . . before there were many big fish, but now there are
only small fish . . . People here [Balobaloang Island] never do this kind of thing
[bombing]. . . Here there are still big fish so we come here to catch them and eat them at
home.”
He said that, when he is lucky, he can get one to two tons per day, and if unlucky,
he only gets one or two hundred kilos. Using traditional fishing methods he says that “if
we fish the whole day, we only get one basket of fish. But if we bomb, we will get a boat
full of fish.” He explained that the trip that day was only for a wedding, but then says that
he bombs even when there is no wedding. “Fishing is long and tiring” and hurts his arms.
Regarding the income generated by his boat, if the crew catches Rp.3,000,000 (US$333)
worth of fish, the crew of about six divides Rp.2,000,000 (US$222) between them, with
the boss getting Rp.1,000,000 (US$111). The income from bombing can be used for the
Haj to Mecca, which is quite common throughout Indonesia, and seems to further justify
the use of blast fishing. For a more detailed analysis on the connection between blast
fishing and religion, refer to Chozin’s MA thesis (2008).
54
3.2 Getting There
The Hapsari video piqued my interest, and I wondered whether the fisherman’s
account of the disappearance of large numbers of fish would be reflected in the archive of
satellite imagery as coral reef loss. Could the progression of damage as fishermen moved
their blasting from island to island be seen in the archive of satellite imagery? To match
sea substrate with satellite imagery, I had to travel to Balobaloang Island and was
accompanied by two colleagues from the Center for Coral Reef Studies UNHAS, Edow
Maddusila and Gusti Hardtiny Kemuning who assisted in locating the sites targeted from
the field map, recording substrate, recording GPS locations, and interpreting in
conversations with locals.
Located at roughly the midpoint on a trade route between Makassar on Sulawesi
Island and Bima on Sumbawa Island, Balobaloang is visited by lambo cargo ships
carrying supplies and various items for trade roughly twice a week, weather permitting.
Due to the lack of public transportation or ferries along this route, catching a ride on a
lambo from Makassar’s Paotéré Harbor bound for Bima or other southern islands is the
best way (and usually the only way) to reach Balobaloang Island. This is the standard
form of transportation for people in the Sabalana Archipelago who need to travel to the
city for rice, fuel, and other supplies for school (Balobaloang Island has an elementary
school with about 250-300 students, as of 1991 – this number was an estimate as no hard
numbers were ever recorded by the school).
55 On June 7, 2006, with Ammarell’s help, we caught a ride to Balobaloang Island
with a friendly crew eager to teach Indonesian and chat about their lives. Though an
engine was used with supplemental power provided by sails catching the wind,
navigation that night lacked the dependence on high tech electronic equipment such as
GPS that is relied upon in other parts of the world. Navigation of the entire route was
done that night following the Bugis tradition of using knowledge of “local wave patterns,
tidal currents, and reefs” (Ammarell, 1999, p. 2), stars, prevailing winds, landmarks like
islands and a lighthouse, and a magnetic compass. According to an experienced sailor
from Balobaloang quoted by Ammarell (1999, p. 106), “a navigator depends upon winds,
the compass, stars, and currents, in that order.” When the crew expects to be within sight
of the island, a member climbs the main mast to adjust the course as needed (see Figure
3.3 below).
Figure 3.3: Balobaloang Island is sighted and still another six hours away, June 2006 (photo by Edow Maddusila).
56
Because of the lack of a deep water harbor on the island, ships anchor in the lee of
the island – thus during the east monsoon of June, the ships anchor off the west coast of
Balobaloang Island – and passengers and cargo is transferred to smaller motorized fishing
boats called jolor in Indonesian (in the local Bugis language: joloro’). (This inter-island
area west of Balobaloang Island will be important in Chapter 5.)
3.3 The Island and the People
Balobaloang Island is an elliptical shape roughly 4.8 km in circumference and
oriented roughly 35° clockwise off the North-South Mercator axis. During our first day
on the island, my colleagues from UHNAS and I walked the foot/bicycle path that circles
the “flat sandy island” (Ammarell, 1999, p. 21).
Houses are generally built on the inland side of the main path, with the best
location on the southeast side of the island because the driving rain and wind during the
northwestern monsoon that causes erosion on the northwest side. The style of the houses
built on the island vary from traditional Bugis houses on stilts with the characteristic roof
(see Figure 3.4 a and b) to one-story concrete houses. The elevation of the island is about
“one to two meters above mean higher high water” (Ammarell, 1999, p. 37). A number of
houses on both the north and south sides have a satellite dish out in front.
57
Though the footpath on the north side of the island was dirt, the portion of the
path on the south side has been recently laid with brick (also visible in the photo below).
This path was freshly paved with bricks made from coral, sand, and cement – another
example of a process destructive to the coral which is occasionally mined, further
degrading the live reef structure. Usually, however, the dead coral rubble which washes
up onto shore is the type of coral used for building such paths on Balobaloang Island
(Ammarell, personal communication).
58
Figure 3.4: Houses on Balobaloang Island (note the abundance of coconut trees); (a) the house on the top is of the traditional Bugis style while (b) the one on bottom is more modern, with tile inside and out (photos by author). (In the photo on the bottom, note the brick path in front which as of June 2006 runs the length of the south side of the island; satellite dishes are not uncommon on the island.)
(a)
(b)
59
Because we arrived in early June, the winds from the southeast monsoon were
building (Tomascik et al., 1997). In the area of Balobaloang Island, the winds tend to
blow in the general direction from east to west (on a Mercator projected map) and were
blowing very strong during the first five days or so. These winds made for difficult diving
conditions on the south side of the island and exploration of the fishing grounds one hour
directly south of Balobaloang Island (Indonesian: Taka Luara; or Bugis: Takaluara) by
jolor had to be aborted because of high waves. This issue will be relevant to the transect
data acquisition in the subsequent data analysis of Chapter 5.
Because of the difficulty in getting into the water on the south side, we changed
plans on the third day and turned our attention to a reef ball project that was begun by
Rita Steyn three years earlier. Before traveling to Balobaloang Island in 2003, Steyn
learned how to build a reef ball, a hollow, spatially complex concrete ball with holes for
fish to swim into for shelter. These balls are commonly used for reef rehabilitation,
providing a solid foundation on which corals can grow. Steyn, together with her
colleague from UNHAS and local villagers worked together to make one small reef ball
(1 m in diameter) and another mini donut shape and placed them at the edge of the reef
crest to the north of the island. Our team located the balls and took photos as well as
placing another one built by Steyn’s team but not yet put into the sea. A growth of both
hard and soft corals of about 30 cm in diameter was seen on one side of the larger ball,
though the smaller one was difficult to locate because of the sand that buried it due to its
60 lack of spatial complexity, as also seen by Fox et al. (2005). [Photos and GPS coordinates
for these positions are in Appendix C.]
One of the most striking aspects of life on Balobaloang Island is the distance of
the island from the nearest city, almost 24 hours by lambo, a motorized cargo ship. The
vast distance between Balobaloang Island and the seat of government in Pangkajene
Kepulauan Regency (one of several regencies in the South Sulawesi Province, and more
commonly referred to as Pangkep) north of Makassar exacerbates the problem of
enforcing the laws that prohibit use of DFPs.
While conducting my field research around Balobaloang Island, there were no
incidents of blast fishing. This struck me as strange because the residents reported
blasting as being almost a daily occurrence. I later found out that just a few weeks prior
to my arrival, a small group of fishermen had been arrested and jailed at the Pangkep
District Jail in Pangkajene for blasting in the area of Balobaloang Island. The lack of
blast fishing during my stay was most likely a combination of both the bad weather (as
reported by McManus et al., 1997; Fox and Erdmann 2000) and the arrest of the
fishermen. Blasting was reported to have resumed a few months after my departure in
late summer 2006.
Along with trade, coconut silviculture is another economic activity on
Balobaloang Island, and in fact every part of the tree is used for food, building, and fuel.
The island is dominated by coconut trees and, though no injuries have ever been reported
from falling coconuts, the occasional falling nut can be disconcerting for one new to the
island. Fortunately, trees are not so close to buildings that a falling coconut would
61 damage the roof. Places also lacking coconut trees include the soccer field and the
pathways, and Ammarell estimated 32,000 trees on the island as of 1991 (1999, p.26). On
the northwestern coast of the island the foundations of the coconut palm trees are
constantly being eroded away and trees often fall into the water.
The people of Balobaloang Island embrace Islam as their religion. There is a large
mosque on the island as well as an elementary school (see Figure 3.5 a and b). In the
middle of the island there is a field that is used for soccer and for camping field trips by
the children. Both the large mosque and the field are visible on the satellite imagery and
will be used to geographically locate pixels in the satellite image analysis in Chapter 5.
62
Figure 3.5: (a) Top: The large mosque on the island and (b) the elementary school. Both were used to locate pixels as ground control points in the data analysis. Photos by Edow Maddusila.
(a)
(b)
63
The food on Balobaloang Island was usually rice and eggs (which we brought
with us) along with fresh fish and the local variation of the spicy Indonesian sauce called
sambal. Eggs are consumed more often when fish are less plentiful during bad weather
(as was the case during our stay). A barracuda served fresh one day was then smoked and
lasted almost three more days, still delicious the last day as the first.
Because the tide during that time of year and month (June 10-16, 2006) was on its
way out by mid-afternoon and would not be deep enough to bring the dive boat in, we
had to finish recording transect data by 1pm, lunch time. However, the ship builders
continued their work until late afternoon and occasionally drew a small crowd of
interested villagers and us. Afternoons were times for socializing and neighbors often
brought with them the most delicious sweet snacks. Reflecting the “widespread
abhorrence of isolation” (Ammarell, 1999, p. 37) on the island, there is a strong sense of
community, and though we were visitors, we were quickly made to feel at home and part
of the community.
Though much of the fish eaten on Balobaloang Island is from fishermen, small
fish and other creatures caught in tide pools within the large intertidal zone when the tide
is out for a few hours in the late afternoon and early evening are easily gathered by
women and children. In fact, the size of the intertidal zone can be so large that “the area
exposed at lower low spring tide is nearly twice as large as the permanently dry land.”
This activity is especially important when the weather is so bad as to make fishing
difficult; many of the fish and gastropods are both eaten and sold in Makassar
(Ammarell, 1999, p. 28).
64
With the outgoing tide during the setting sun at that time of year, many women
and children are seen with baskets, walking on the seagrass and even on parts of the
shallow corals. On one occasion I walked out into the intertidal zone, which begins as the
seagrass and shifts to coral. The coral dominating this area is a fast growing hard coral,
called Acorapora, and is resilient to the damage from trampling. Upon returning to the
beach, some children showed us the sea cucumber (teripang) which are also sold in
Makassar, sea urchin, and pufferfish they had captured in the tidal pools (see Figures 3.6
a through f). Pet (1997) has described this trampling as one of the destructive processes,
though the nature and extent of the damage needs to be further investigated and is beyond
the scope of this study.
Other animals of note on the islands include chickens and swans (used for eggs),
toke house lizards (40 cm lizards named for the distinctive night call “to-keeeeeeeee”),
cats, and, in the past, a few horses. Cats are useful for controlling mouse populations, but
are also sometimes kept as pets, as was the case at the research station.
65
Figure 3.6: (a) & (b) top: people walking in the intertidal zone, looking for creatures trapped by the outgoing tide; (c) center left and (d) center right: a sea cucumber (teripang) caught in a tide pool, (e) bottom left: a sea urchin, (f) bottom right: a puffer fish caught, Balobaloang Island, June 2006 (photos by author).
(a)
(b)
(c) (d)
(e) (f)
66 CHAPTER 4. MARINE APPLICATIONS OF REMOTE SENSING IN MONITORING
REEF DAMAGE FROM BLAST AND CHEMCIAL FISHING
Much of the published research on the status of Southeast Asian coral reefs is out
of date and/or difficult to locate. Some of this is so generalized as to be unusable for local
resource and MPA managers because it only provides estimates and, in some locations, is
just plain incorrect. Any monitoring of the coral reef status that is being done is not being
published internationally, where it can have the greatest impact. From the latest
international conference, 11th International Coral Reef Symposium (ICRS), it is clear that
Lansdat remote sensing scanners are not being used in monitoring coral reef damage
from DFP use, either locally or at the national level, within Southeast Asia. The research
using remote sensing techniques to map coral reefs is currently only aimed at finding uses
for the newest and most expensive technologies. As such, it is also inaccessible for local
MPA and resource managers with limited budgets.
Many potential users may be scared off by the obstacles specific to marine remote
sensing, including the cost of the newer tools. Other obstacles are specific to marine
environments, and those familiar with land use and land cover imagery do not have to
deal with such problems. There are many variables that affect the water column and
directly impact the reflectance of the benthos (sea bottom). Landsat is viewed as an
obsolete tool for use in such applications because of its large spatial and spectral
resolutions. This paper aims to show that Landsat can indeed be useful as well as a
67 simple and cost effective tool for resource managers for detecting coral reef loss, despite
the technical difficulties.
4.1 Obstacles to Current Research
In doing the background research for this project, there were the two main
shortcomings in the research on blast and chemical fishing that were encountered. These
involve the age and inaccuracy of the data and the inaccessibility of the literature to those
not well versed on the organizations and researchers involved in the research. One would
hope that programs aimed at increasing awareness of the national and international
networks and the effects of consumer choice on far-away reefs would publish current
information that is easy to understand. Within the remote sensing literature, the
methodologies were found not to address the temporal effects of those particular
destructive fishing practices in a multi-date fashion so as to present the geographic spread
of the effects within a given area. Reports of bleaching events were post-event-driven and
none investigated the effects of anthropogenic DFP use on coral reefs.
Problems with Current Coral Reef Status Estimates
Currently very little research is being done on blast or chemical fishing in
Southeast Asia when compared to research being done on other global threats such as
global warming or ocean acidification. From a review of published literature and
68 attendance at the 11th International Coral Reef Symposium (ICRS) in Ft. Lauderdale,
Florida, July 7-11, 2008, it seems research on blast fishing was a only a hot topic up to
six years ago, and in recent years has fallen by the wayside; only two presentations at the
conference dealt with blast fishing (and one poster presentation which was Chozin’s
[2008]), none with chemical fishing, and no presentations in among two days of remote
sensing panels dealt with either DFP method. In conversation, one attendee (a geologist)
even commented that ocean warming and acidification become irrelevant if the living
coral reefs are blasted to bits. This lack of coverage may be because the conference was
not held in Asia, though with such an important topic, more than two presentations
should be given in a highly visible international conference specific to coral reef issues
that is held only once every four years. In a search using Google News on Sunday July
13, 2008, 174 hits were returned in a search using the phrase “11th International Coral
Reef Symposium”, including a variety of international news sources; 43 of these
mentioned “acidification”, but none mentioned blast or chemical fishing (or any other
descriptions of the activities).
There is quite a bit of work on reef rehabilitation techniques especially for areas
to have suffered from extensive blast fishing, with a number of private companies doing
such work. These companies are the few that give voice to the problem of destructive
fishing. The research that has been done on blast and chemical fishing is difficult to find
beyond reef conservation circles and is only accessible to those knowledgeable of the
organizations involved in the research (such as the WWF, ICRAN, NCRI, etc.). For the
lay person to find the relevant research, he or she must be proactive and first learn about
69 the many groups involved. The research is not readily available in outreach programs as
is seen with carbon dioxide reduction issues.
Works cited in Alcala’s Blast Fishing in the Philippines, With Notes on Two
Destructive Fishing Activities (2000) proved difficult to locate, with many of her
resources unpublished, which is not uncommon in the literature on blast and chemical
fishing. When contacted for funding opportunities for this project, Lauretta Burke of the
World Resources Institute (WRI) in Washington D.C. and an author of one of the few
comprehensive papers on the topic, Reefs at Risk in Southeast Asia, replied that there
were no plans to continue research on the subject in Asia and they were not currently
funding any projects (personal communication, July 2006).
Currently only estimates are available for the risk of damage from destructive
fishing and hard research with empirical data has proven difficult to come by in English
or in Indonesian. Apparently only calculating an estimate for threats to reef health in
2002 is sufficient. The data from the WRI project have been incorporated into a ReefGIS
database with other datasets (see http://reefgis.reefbase.org/) that are interesting, though
in at least the case with the present area of interest, inaccurate. The datasets used in Reefs
at Risk in Southeast Asia classifies the Sabalana Archipelago as “low threat” overall (see
Figure 4.1), and does not even break down the threats past “destructive fishing” into
categories of “blast fishing” or other DFP methods. In Chapter 5, this classification will
be shown to be incorrect. Unfortunately, the WRI publication is perhaps the most recent
and most visible to address destructive fishing effects, and was found to be the most
70 commonly cited reference with regards to destructive fishing practices at the ICRS
conference.
Figure 4.1: Southeast Asian reefs threatened by destructive fishing from Reefs at Risk in Southeast Asia (Adapted from: Burke et al., 2002, p. 29). The study site of this project is shown to be at a low threat level from destructive fishing.
71
Problems with Reef Status Monitoring
Another shortcoming in the literature is the methodologies in recording the
current health of coral reefs. One of the most widely used methods worldwide is used by
Reef Check (www.reefcheck.org), a Los Angeles based international nongovernmental
organization which uses volunteers to survey the reefs, employing an on site line transect
method. While snorkeling, the volunteer records the fish observed, type of substrate, and
any diseases or invasive species within a ten meter section, skips ten meters, then records
observations for the next ten meters, and so on (Reef Check, 2004). This line transect
method is useful in very species-specific record keeping for a small area, though there is
no protocol for recording the latitude and longitude for start and end so that a longitudinal
study over time can be conducted. If properly trained however, volunteers can provide
valuable research data (Crabbe et al., 2004).
The Reef Check reef status reporting method is not very useful in covering large
habitat-scale areas such as those of an entire marine protected area (MPA), and can only
detect large, discrete changes visible to the observer. Given the economic constraints of
in situ surveys, this method can be cost effective. Similar to the Reef Check method, Lam
et al. (2006) showed that a continuous video transect can detect small changes and is
preferable to point intercept transect (PIT) where the cover is recorded at a designated
distance along the line (such as every 1 m or 10 cm), if economically feasible.
72
Real and Perceived Cost Effectiveness of Satellite Imagery
Regarding remote sensing methodologies, satellite imagery has been used to map
the reefs worldwide, though conservation agencies are still reluctant to routinely use such
technologies in their reef monitoring programs (Dekker et al., 2001, cited in Malthus and
Mumby, 2003), where cost is considered to be the main hindrance of habitat mapping
(Mumby et al., 1999). It is useful in that it can detect “pattern changes across a near-
continuum of spatial scales” because of the ability to sample “an entire statistical
population (e.g. the entire reef)” (Malthus and Mumby, 2003).
A survey of the most cost effective remote sensing instruments found that, if there
are no set-up costs (hardware or software), acquisition of satellite imagery accounts for a
smaller percentage of the total project cost when compared to digital airborne sensors and
air photo (analog) interpretation. Furthermore, if only a “coarse descriptive resolution
(e.g. coral/seagrasses [sic]; mangrove/non-mangrove) is the requirement [as is the case in
the present study in the Sabalana Archipelago] satellite sensors will be the most cost
effective option and reasonable accuracy (~60%-80%) should be expected” (Mumby et
al., 1997).
In 1999 the Institute for Marine Remote Sensing (IMaRS) at the University of
South Florida, funded by NASA’s Oceanography Program, began a project to map all
shallow water reefs worldwide within a 15 m depth, called the Millennium Coral Reef
Mapping Project (abbreviated the “Millennium Coral Project” in this paper). The goals of
this project are stated as: “ to provide a reliable, spatially very well constrained data set
for biogeochemical budgets, biodiversity assessment, reef structure comparisons and will
73 also provide critical information for reef managers in terms of reef location, distribution
and extent” (http://www.imars/usf.edu). Landsat scenes that had the least cloud cover
which contained reef, as well as the land adjacent to these areas, were arranged in a
mosaic and all bands were made available for download from the website for research.
The full compliment of bands is available, including the near-infrared and infrared bands
usually considered useless in marine remote sensing. Through the Millennium Coral
Project, an archive useful for future baseline studies, has been created. (See Figure 4.2 for
an example of imagery of the Sabalana Archipelago study location downloaded for free
from the Millennium Coral Project website.)
In a study published in 1999 before the launch of the high resolution IKONOS
(with 4 m multispectral bands and a 1 m pan-chromatic band) and Quickbird satellites,
Mumby et al. (1999) pointed to various factors that affect the cost effectiveness of remote
sensing for tropical coastal resource assessments: the objectives of the mapping,
availability of the hardware, size of the area of interest, technical background of the staff,
the level of accuracy of output maps, and the cost of data acquisition. The time, cost, and
effort were found to be higher in boat-based survey, and satellite based remote sensing
was found to be much more reasonable in terms of cost for habitat mapping in Mumby et
al. (1999).
Recently scientists have been able to use satellite imagery to map the biotic
(living) substrate in given areas to the species level, such as the giant clam (Andréfouët et
al., 2005; Purkis et al., 2006). Making this process possible was the launching of
IKONOS in 1999. With a 5 m resolution per pixel, IKONOS was seen as much more
74 preferable to the Landsat satellite at a 30 m resolution (Elvidge et al., 2004). For this
project in the Sabalana Archipelago, both IKONOS and Landsat imagery were priced.
The cost of IKONOS proved to be much higher (as of spring 2006) costing nearly
US$2000 for a scene minimum of 100 km2 (Space Imaging quoted a new order with no
existing archive – the case with the Sabalana Archipelago – at US$19.80/km2 with a
minimum of 100 km2), whereas Landsat was US$350 per 185km2 when purchased from
the U.S. Geological Survey (USGS) though Ohio University’s membership in the
OhioView Project (a consortium of ten Ohio universities and partners, -- including
NASA Glen Research Center, USGS EROS Data Center, and the Ohio Library
Information Network [OhioLINK] -- formed to make the satellite data more accessible
and to assist with remote sensing research). However, archived Landsat data stored in
Australia was not quoted at a discounted rate and cost AU$1000 (about US$750)
(Geoimage Pty Ltd, Australia, personal communication, 2006). Thus, as size of the study
area increases, so does the cost of satellite imagery.
Adding to the research cost is any acceleration of the processing time. Elvidge et
al. (2004) had to pay US$10,000 for an expedited IKONOS image acquisition in 2003 of
the area around Great Keppel Island in the Great Barrier Reef (14.5 km2 plus surrounding
water). Furthermore, IKONOS still has the same spectral resolution as Landsat; if it could
more finely divide the spectrum to more than five bands (as in hyperspectral satellites
that can record over 250 bands in the electromagnetic spectrum – roughly 50 of those in
the visible portion of the spectrum, thus useful in marine remote sensing) the fine
resolution would make the advantages worth the cost. But it does not.
75
The Advantage of the Landsat Archive
Because the high resolution and hyperspectral satellites have only recently been
introduced, relative to the Landsat program which began in 1972, the archive does not
exist to allow for longitudinal studies using the newer satellites. The Landsat 5 TM
scanner launched in 1984 has been recording 30 m resolution images continuously
between 81°N and 81°S latitudes, returning to the same site every 16 days.
The extensive archive of Landsat TM makes it a useful tool in detection of
expanding areas of unvegetated sand bottom as coral is lost from human impacts
(Luczkovich et al., 1993; Vanderstraete et al., 2006; Lubin et al., 2001). The current
spatial resolution of 30 m in the red, green, and blue bands (3, 2, and 1, respectively) date
back to the 1982 launch of Landsat 4 with a TM scanner; the spatial resolution in the
Multispectral Scanner (MSS) scanner on Lansdat 1 to Landsat 3 archive is 80 m between
1972 and 1983. The problem of the lack of a satellite image archive in the newer
satellites has been overcome in some projects by digitizing aerial imagery, scanned at 300
dpi, resampled to 2 m pixel size, and finally geocorrected the images (Palandro et al.,
2003); however aerial photos do not exist for many locations that are covered by the
Landsat archive, as is the case with the Sabalana Archipelago.
With a large program creating such a large archive as the Landsat program, it
becomes difficult to store all of the information in one location. There are twelve
International Ground Stations (IGSs) that download the data from Landsat 5 TM and five
that download the data from Landsat 7 ETM+, two of which serve only Landsat 7
76 (http://landsat.usgs.gov/about_ground_stations.php). For this project, the archived
imagery was held in the Alice Springs, Australia IGS which was for sale through
approximately ten Australian companies. Of the five of these companies responded to
requests for purchase, two responded that they do not sell imagery to users from foreign
countries. In fact, there is one IGS in Parepare, South Sulawesi, Indonesia (just north of
Makassar) run by the Indonesian National Institute of Aeronautics and Space (LAPAN)
(www.lapanrs.com). The problem of politics in purchasing remote sensing imagery of a
foreign country can become an obstacle when researching sensitive issues such as illegal
blast and chemical fishing and the associated corruption that allows these activities to
continue. Fortunately, Landsat 7 ETM+ imagery was not identified for purchase in this
project and such issues did not need to be dealt with.
4.2 Problems Specific to Remote Sensing in Marine Environments
In addition to the challenges faced by terrestrial remote sensing projects, remote
sensing of the marine environment presents additional challenges of scatter and
interference from the water surface and water column. However, the at-satellite
reflectances measured above the atmosphere which are affected by scattering can still be
useful as “the radiance contrasts between most coral species and most brighter noncoral
objects remain noticeable for water column depths up to 20 m.” This supports other
research showing that “coral reef identification should be feasible using [Landsat]
77 satellite remote sensing, but that detailed reef mapping (e.g. species identification) may
be more difficult” (Lubin et al., 2001).
Spatial Resolution Issues
The biggest problem in using imagery with coarse resolution (large pixels) as with
the Landsat TM and ETM+ scanners (with 30 m pixels) results from the mixture of
different types of cover within the pixel. Because coral reefs are composed of small
groups of animals living within close proximity to other types of biotic substrate (e.g.
algae and seagrass) and abiotic substrate (e.g. rock, rubble, sand) many different types of
benthic cover can be found within one pixel. This problem is more commonly referred to
as subpixel mixing. Mumby et al. (1998) noted the problem of the sensor’s resolution
making it “incapable of distinguishing reef features at subpixel scales.”
The coarse resolution of Lansdat produces accuracy issues some find problematic.
Landsat was found to be 15-20% lower in accuracy than IKONOS throughout the range
of habitat complexity (Palandro et al., 2003). However, the Landsat accuracy was found
to be within acceptable parameters for marine remote sensing applications before the
launch of IKONOS in 1999 (Mumby et al., 1997). This is the main reason many have
decided to forego use of Landsat in marine applications in lieu of IKONOS and airborne
sensors. Accuracy, as well as price, increases significantly with higher resolution
scanners.
Fortunately the scanner assigns a brightness value (BV) to the pixel based on an
average brightness of all substrate within that pixel. Thus, when there is an increase in
78 brightness in a part of the pixel, this will result in an increase in BV of the entire pixel.
As noted earlier, when corals die and expel the symbiotic zooxanthellae, they experience
a bleaching effect. The average increase in such a large pixel may result in an
overestimation of the spatial scale of the brightness increase if measuring the area of the
brightness increase.
Atmospheric and Water Column Attenuation
Problems also result from refraction when the electromagnetic radiation passes
from air to water, when sedimentation or other impurities are present in the water
column, when glint and glare reflect off the water surface, and when there are waves
(with their height and motion). With the IKONOS satellite, the glint from sunlight off the
surface can be corrected for by using the “off-nadir pointing capabilities” of the scanner
which makes it “possible to specify view angles that minimize image contamination”
(Elvidge et al., 2004). To correct for challenges, technical constraints involving the
viewing geometry have been used by a sensor elevation of 70 to 85 degrees and “viewing
west from the east (view azimuth of 5 to 175 degrees)” and a cloud cover target of 80%
cloud free (Elvidge et al., 2004). This is not possible with Landsat and so glint removal
algorithms have been developed “to correct for wave induced specular reflection” (Purkis
et al., 2006).
Corrections have been performed to account for water surface roughness due to
wind generated wave patterns and associated glint and depth by Andréfouët et al. (2003).
These processes are useful when producing a single date, classified map showing the
79 areas that include different types of substrate. The depth variability problem within
marine remote sensing happens when an increase in depth changes the bottom
reflectance. For example, sand that is brighter at shallower depths is darker at greater
depth, at 20 m it may look like seagrass at 3 m, which is darker (Mumby et al., 1997).
Lyzenga (1978) developed a depth invariant processing algorithm to compensate for this
effect and has become commonly used in a variety of projects, as were seen at the ICRS
conference in Ft. Lauderdale mentioned earlier.
4.3 Using Landsat to Assist in Coral Reef Management Efforts
Since the introduction of the high resolution multispectral satellites and
hyperspectral aerial scanners and satellites (both very expensive), Landsat has largely
been deemed obsolete for marine remote sensing within the academic community now
focused on using the newest technologies. These expensive technologies may be
prohibitively expensive for the budget-restricted reef management groups in developing
countries where the highest coral species diversity is found (the six countries of the Coral
Triangle Initiative are Indonesia, Malaysia, Philippines, East Timor, Papua New Guinea,
and the Solomon Islands - all developing countries). Landsat can still be useful in certain
cases, and has been shown to be incredibly cost effective in studies that assess a few
broad classes (e.g. live coral, algae, seagrass, sand, etc.) rather than more detailed reef
issues (Bouvet et al., 2003).
80
Though many reefs have been mapped worldwide with a variety of sensors, no
published longitudinal studies using remote sensing technology have been undertaken of
a location known to have experienced blast or chemical fishing. This type of study should
be relatively easy, using the increase in brightness that occurs with zooxanthellae loss
when coral death is experienced as a basis for the mapping. The areas that have
experienced such shift from healthy coral reef to dead rubble should appear as patchy
increases in brightness from year to year which can easily be detected from space (as
opposed to a larger scale increase in brightness as would be seen resulting from storm
damage or coral bleaching).
The present study aims to use these qualities to map the damage as reported by
residents of Balobaloang Village. The people of Balobaloang mentioned in both formal
interviews with Hapsari (2008) and in informal discussions with me that the fishermen
who use chemical and blast fishing in the area come from Sumanga’ Island do so because
the fish around their island are no longer found in the high numbers that they are around
Balobaloang Island.
The data analysis in Chapter 5 will use Landsat satellite imagery to investigate the
habitat-scale change over 15 years, from 1991 to 2006, by using the increase in relative
brightness as the habitat shifted from live coral-dominated to dead-coral rubble; it will
also look for the spread of damage to the reefs as fishermen using destructive fishing
practices progressively exhausted the resources.
Using the extensive Landsat archive, this paper aims to show the spread of
damage from one island to the other and to the Taka Luara fishing grounds to the south of
81 Balobaloang Island and to the west of Sumanga’ Island. The dramatic visual display of
how much area of live reef has been lost and where the damage came from will hopefully
become yet another tool to help the people of Balobaloang Island in their endeavor to
protect their reefs. While gathering feedback from villagers for her video project using a
preliminary ten minute sequence, Balobaloang viewers said that they were happy: “we
are not afraid anymore because we have evidence . . . before we didn’t have any
evidence, so we were afraid. Now we have the tape, we can prove it. Before, although we
had some evidence, it didn’t reach the authority. It’s not like now” (Hapsari, 2008).
The end users of this project are intended to be both residents of the Sabalana
Archipelago in their struggle against the fishermen using illegal techniques, high school
and university teachers and students of South Sulawesi interested in learning a method to
monitor reef health over a large area, and marine resource managers in monitoring DFP
use and the resulting habitat. The teachers and student can use this method to graphically
display reef loss in a more accurate way than that in Reefs at Risk in Southeast Asia. And
by showing that Landsat is still useful for monitoring coral reef condition, managers with
limited budgets should be able to cost effectively and accurately monitor the damage
from destructive fishing at a habitat-wide scale such as in large marine parks. They can
also use this tool to target specific areas for policing and rehabilitation within a large
area. Furthermore, the transect data is specifically included in Appendix B to serve as
baseline data to monitor the progress of future reef rehabilitation projects.
82
Figure 4.2: Location of study area, Landsat Bands 3,2,1 in RGB (raw data source for satellite image from the Millennium Coral Project; raw data for the GIS from ESRI).
83 CHAPTER 5. VISUALIZING THE PROBLEM OF DESTRUCTIVE FISHING IN THE
SABALANA ARCHIPELAGO
The following data analysis within this chapter is a temporal study investigating
whether the claims of locals are reflected in the archive of satellite imagery. Many have
said that the damage from blast and chemical fishing started around Sumanga’ Island,
became much more intense in the mid-1990s, and then spread to the reefs surrounding
Balobaloang Island and the Taka Luara fishing grounds after the Sumanga’ reefs became
unproductive. Using five satellite images from 1991, 1992, 1995, 1999, and 2006,
brightness values were subtracted to map the change in reef cover. Here the term change
was defined as an increase in brightness of the pixel. This brightness increase can happen
with the expulsion of zooxanthellae (symbiotic algae) from the coral polyps after being
damaged from blast and chemical fishing. All four change images were combined into
one map to visually display the spread of damage over time. Results were found to be
consistent with the expected patchy increase in brightness that occurs from intermittent
use of these two particular DFP methods in the reef crests. However the spread from
Sumanga’ Island to other areas over the time period examined within this paper was not
reflected in the dates chosen for this particular study.
84
5.1 Digital Change Detection
Scale of Investigation of a Highly Complex System
The term ecosystem means many things to different people. Before undertaking
ecosystem management, one needs first to give a “clear and practical definition of the
ecosystem” with the definition using boundaries and scales rather than components and
functions (Hatcher, 1997). Within marine remote sensing, the boundaries must be
carefully defined at the habitat scale, highlighting trends (Palandro et al., 2003). This is
the most specific level possible with Landsat satellite imagery, given the high level of
amalgamation of creatures and other abiotic substrate within the reef. Field data is often
classified according to habitat classes, where the term habitat as in Mumby et al. (1998),
“embodies species assemblages and associated substrata; coarse descriptive resolution
would be simply” defined as coral, algae, sand, and seagrass. Because of the inability to
accurately map benthic habitats, change detection has been “confined to large scale
phenomena such as seagrass die-off or mangrove deforestation (Mumby et al., 1998) as
“different patterns emerge at different scales of observation” (Hatcher, 1997). When the
level of accuracy investigated is at the habitat level, only coarse resolution is necessary as
is the case with the Landsat scanners (Mumby et al., 1999). The coarse, ecosystem scale
defined in Mumby et al. (1999), Hatcher (1997), and Palandro et al. (2003) were used to
define the scale used in this project, where coarse, habitat-level coral death is the subject
of analysis.
To investigate this broad-scale coral death, five images acquired by two space
based scanners were used in a change detection process to map the brightness increase
85 resulting from coral death over a fifteen year period. These two scanners were the
Landsat Thematic Mapper (TM) aboard the Landsat 5 satellite and the Enhanced
Thematic Mapper (ETM+) aboard the Landsat 7 satellite. These scanners have the same
spectral resolutions (area within the electromagnetic spectrum recorded in each band) and
the same spatial resolutions (i.e. pixel sizes) at 30 m in the visible and infrared portions of
the electromagnetic spectrum. The main differences between the two scanners are in the
increased spatial resolution in the far-infrared thermal band (band 6) from 120 m in the
TM to 60 m in the ETM+, as well as the addition of a 15 m panchromatic band (band 8)
in the ETM+ scanner (See Table 5.1). None of these differences are relevant to this study.
Ucuncuoglu et al. (2006) found that both TM and ETM+ scanners can be used within the
same project for a multi-year change detection study.
86 Table 5.1: Comparison of Landsat TM and ETM+ Scanners (EMR = Electromagnetic Radiation portion of the spectrum, IR = Infrared, Pan = Panchromatic; only bands 1, 2, and 3 reflect the radiation in the visible portion of the EMR spectrum and are useful in marine remote sensing)
(A) Thematic Mapper (TM) EMR (B) Enhanced Thematic Mapper (ETM+)
Band Number
Spectral Resolution
(µm)
Spatial Resolution/ Pixel Size (meters)
Band Number
Spectral Resolution
(µm)
Spatial Resolution/ Pixel Size (meters)
1 0.45-0.52 30 m Blue 1 0.45-0.515 30 m
2 0.52-0.60 30 m Green 2 0.525-0.605 30 m
3 0.63-0.69 30 m Red 3 0.63-0.69 30 m
4 0.76-0.90 30 m IR 4 0.75-0.90 30 m
5 1.55-1.75 30 m IR 5 1.55-1.75 30 m
6 10.4-12.5 120 m IR 6 10.4-12.5 60 m
7 2.08-2.35 30 m IR 7 2.09-2.35 30 m
Pan 8 0.52-0.9 15 m
Source: NASA (2008) http://landsat.gsfc.nasa.gov/about/tm.html
Source: NASA (2008) http://landsat.gsfc.nasa.gov/about/etm+.html
In this study, the reefs were analyzed at the depth of greatest EMR penetration
within the fringing reef around the islands and the fishing grounds of Taka Luara. The
habitat-scale coral death was explored though an increase in brightness values of the
pixels using the blue band (band 1) which has the greatest depth penetration of all
Landsat bands (Lyzenga, 1981; Lubin et al., 2001; Vanderstraete, 2006).
87
Detecting Coral Death from Space
All imagery used in this project was the Landsat system of Earth observation
satellites. With the proper choice of band, the bottom reflectance (thus substrate) can be
determined to depths of up to 15 m in clear ocean water (Lyzenga, 1981). As described in
Chapter 3, the waters of the Sabalana Archipelago area particularly well suited for such
investigation because of the distance from land and the associated sources of turbidity.
Philpot et al. (2004) suggested that bottom type can be mapped in waters as deep as 20 m.
Regarding the effects of blast fishing, Steyn (2005, p. 42) found that the depth where
corals were most heavily impacted was at 10 m, though divers were observed collecting
fish as deep as 17 m when the bomb was set to explode in the water column and the fish
sank to the bottom (see Figure 3.1 for a copy of the navigational/depth chart of the
Sabalana Archipelago). Thus, Landsat should be useful in mapping the damage from
destructive fishing around the Sabalana Archipelago.
Philpot et al. (2004) found that in very shallow waters, the ~400 nm – 720 nm
(blue to near infrared) portion of the electromagnetic spectrum is useful for detecting
coral reef cover. However, for depths greater than a few meters, the ~400 nm – 600 nm
portion of the spectrum (visible blue to green) is preferable because of the inability of
near infrared to penetrate water (and the reason why divers notice loss of color at depth
and must use a flashlight to see hues of red) (Philpot et al., 2004). This optimal range
covers bands 1 and 2 of the TM and ETM+ scanners. The infrared portion of the
spectrum (bands 5 and 7) however, is also helpful in isolating non-submarine features
88 such as land and clouds to allow for masking (deletion) of these elements from the scene
to focus on reefs.
In measuring sandy bottom cover, Luczkovich et al. (1993) found Landsat TM
band 1 to be the most useful in measuring coarse bottom types. Though Call et al. (2003)
found band 2 to best map bleached coral (560-590nm) and deep coral (590-600nm), the
increases in brightness can be seen in both bands 1 and 2, with band 3 being the least
useful because of the shallower depth limitations (Michalek et al., 1993). Vanderstraete et
al. (2006) used all three Landsat bands in the visible portion of the spectrum (bands 1, 2,
and 3) because a previous study had established the depth of penetration to be 25 m, 15
m, and 5 m, respectively. Lubin et al. (2001), when investigating the spectral signatures
of various bottom types and coral species, found that band 1 to “be well suited for
distinguishing living coral reefs from most surrounding objects . . . and that band 2 “is
less well optimized for coral reef identification”.
Hochberg et al. (1998) established the distinct reflectances between bleached and
healthy coral using aerial spectrometers. Of all the measures of coral health, the loss of
zooxanthellae seemed to be the only measure of coral health that is detectable by remote
sensing because of the “loss of colour [sic]” in the corals “and therefore change in
spectral reflectance” (Holden and LeDrew, 1998b). This study found that healthy and
dead coral do have spectrally distinct reflectances “based largely on the magnitude of
reflectance”. Michalek et al. (1993) also noted the increase in brightness seen after coral
death from the expulsion of symbiotic algae and the subsequent loss of color.
89
In studying the widespread effects of bleaching, Elvidge et al. (2004) found an
increase in brightness in band 1 and band 2 [using the IKONOS satellite which has
similar spectral recording capabilities to Landsat] of corals in waters as deep as 15m,
though bleaching was not detected in band 3. Distinguishing between bleached coral and
cloud was based on the change in the coral spectrum, so that the “radiance spectra of
clouds [were] brighter in all spectral bands and could be easily distinguished from the
bleached coral (Elvidge et al., 2004). Most important to the present study in the Sabalana
Archipelago, bleached coral was found to be twice as bright as unbleached coral (see
Figure 5.1 below; Clark et al., 2000). In addition to this study, Holden and LeDrew
(2002) used a hand held spectrometer measuring the spectral signature 15 cm above the
features and compared these measurements to photographs that were taken to coincide
with the images. They found bleached and healthy corals to have distinct reflectance
spectra as well.
90
Figure 5.1: Reflectance of live vs. dead coral as measured by boat-mounted portable spectrometers (within a 3 m depth). Here “old dead” coral has been dead more than 6 months (source: Clark et al., 2000).
5.2 Project Objectives
The goal of this study was to evaluate the usefulness of Landsat TM and ETM+
scanners in mapping the effects of blast and chemical fishing in the Sabalana
Archipelago, an area known to have experienced extensive, almost daily blasting as well
as an unknown amount of chemical use to catch fish. The maps produced were to provide
evidence of fishery damage reflecting the observations of locals that reef loss since the
1990s as a result of blast and chemical fishing and the spread from Sumanga’ Island to
other areas within the archipelago as resources were progressively exhausted.
The questions answered by using change detection between five satellite images
from different dates addressed the geographic nature of the change in two key aspects.
91 First, the change sought to answer the question of whether the patchy increases in
brightness seen in blast craters and rubble “killing fields” resulting from blast fishing and
the bleaching resulting from chemical use of cyanide to stun the fish (which also kills
symbiotic zooxanthellae resulting in color loss in coral polyps) could be seen in a change
image. The change resulting from these two destructive fishing methods was expected to
be characterized by a patchy brightness increase (i.e. brightness increase in a relatively
small number of pixels) throughout the image rather than a general increase in brightness
over the whole area as would be indicative of a coral bleaching event (as results from
temperature, salinity, or increase in any number of other factors to which coral polyps are
sensitive).
The second aspect of the geographic nature of the change within the Sabalana
Archipelago was the spread from the origin, Sumanga’ Island where the bombers live, to
the other parts of the archipelago. Because of the accounts of the people from both
Balobaloang Island (in informal discussions) as well as the admissions from the bombers
themselves (Hapsari, 2008), the patchy increases were expected to be around Sumanga’
Island first and then progressively spreading to the other islands as well as to the Taka
Luara fishing grounds. Furthermore, there were anecdotal accounts that the fishermen
using cyanide mainly concentrate their efforts in the Taka Luara fishing grounds. These
activities were reported to have taken place mainly since 2003. If enough images were
used and in the proper time period, the spread of patchy damage was expected to be
reflected in the sequence of change images. As for the timing, the blast fishing was
92 reported to have begun after WWII, though took place in earnest in the mid-1990s; thus,
the imagery purchased for this project was mainly in the 1990s.
5.3 Methods
Within this project change was defined as the increase in brightness value of
pixels. This change detection project within the Sabalana Archipelago investigated
whether or not a change had occurred. It was not intended to be able to identify the
specific nature of that change (e.g. coral to rubble, seagrass to sand, rubble to sand, etc),
through it is known that coral experiences an increase in brightness when it expels its
symbiotic algae after blast or chemical fishing methods are used nearby. In order to
detect the nature of the change, a post-classification change detection would have had to
be done, requiring much more time and funding than available. Furthermore, detailed
prior knowledge of the substrate in both before and after images would have been
required in order to produce an accurate supervised classification of both images before
differencing. However, when the present results are combined with the local accounts of
the history of the area and in situ observations, the change detection image resulted in an
increase in brightness in areas where coral death was reported (and observed) as having
resulted from the blast fishing method. This image differencing method was found to be a
simple and relatively inexpensive method to accomplish the project goals.
93
This brightness value change image was produced using a pre-classification
method between five images over a fifteen year period. Four of the five images were
from the 1990s, when the blast fishing was reported to have accelerated in use. Upon
locating the areas where brightness was found to have increased, the mid-infrared band
(band 7) of the later date within the pair was used to create a land/cloud mask to edit out
the changes that resulted from these two non-marine features. The output images were
compiled into one user-friendly map, showing all areas in each of the four change images
overlaid (1991-1992, 1992-1995, 1995-1999, and 1999-2006). This map was intended for
use by the villagers of Balobaloang to provide feedback on these areas and to assess the
accuracy and the usefulness of the process.
Image Processing Prior to Field Research
Bouvet et al. (2003) showed that Landsat imagery is useful to identify areas for in
situ investigations, which was the reason for creating an unsupervised classified field
map in this project. Before traveling to the research site, a field map was produced to
target areas for investigation. Raw unprocessed satellite imagery data for the area was
located at the Millennium Coral Project website at the Institute for Marine Remote
Sensing (IMaRS) at the University of South Florida in St. Petersburg, FL and
downloaded (http://www.imars.usf/edu). The image was acquired on September 20, 1999
by the Landsat 7 ETM+ scanner and subsequently used as part of the Millennium Coral
Project mapping all of the shallow water coral reefs worldwide and made available for
use on the website.
94
Using this image, an unsupervised Isodata classified image was produced via the
ENVI 4.2 software. Both Isodata and K-Mean algorithms were available in the program
as the two unsupervised classification methods. The Isodata method was found to be
more useful because the number of classes in the image were unknown and the Isodata
algorithm “allows for different number of clusters while the k-means assumes that the
number of clusters is known a priori” (Yale Center for Earth Observation Landcover
Classification Project). The Isodata algorithm was used to create twelve different
unsupervised classified maps in a trial-and-error method, and the sixth iteration was
found to be the best. This determination was made through prior knowledge of the
patterns of reef geography (reef slope, reef crest, etc.) as described in (Tomascik et al.,
1997). 20 classes were arbitrarily mapped by the computer, and those classes known to be
land or cloud were deleted from the image, using the depth chart in Figure 3.1 as
reference, leaving 11 classes of submarine benthic cover. This was similar to the deep-
water masking that was performed for depths greater than the 20 m threshold by Philpot
et al. (2004). These 11 classes were arbitrarily reassigned colors for better separation for
ease of use in the field. Figure 5.2 below shows (a), the large classified map covering the
entire Sabalana Archipelago (b) the subset of sites targeted for visitation, and (c) a close-
up of Balobaloang Island surroundings for a more detailed investigation.
95
Figure 5.2: (a) Classified image of the Sabalana Archipelago, (b) subset of potential dive sites, and (c) the primary field research map, close-up of dive sites around Balobaloang Island (raw data downloaded from the Millennium Coral website; all maps produced by the author).
96
Field Data Collection
Upon arrival at Balobaloang Island, two local fishermen were shown the Isodata
field map, told that each color represented a different type of unknown bottom cover as
categorized by a computer program, and were asked their opinions about what the colors
might represent. One fisherman identified the large area of red on the western side of
Balobaloang Island as being an area of intense daily blasting. Many areas identified for
substrate observation were identified by local fishermen with knowledge of the reefs;
areas not visited in this manner were identified by color and visited later.
Transect protocol used was a variation of that used by Reef Check volunteers
(www.reefcheck.org). However, rather than recording the substrate every 1 m (which was
determined to be inappropriate for comparison with the 30 m pixels of the TM/ETM+
satellite imagery), and given the on-site time constraint, a general estimation of the
substrate within the area was recorded within a given 30 m area. Substrate was estimated
for percent cover of the various types (live coral, dead coral covered by algae, rubble,
sand, seagrass, rock) within the transect and photos were taken in panorama as well as
close-up of the bottom. Areas targeted for investigation were as close to uniform cover as
possible (e.g. area entirely composed of rubble); areas of significant substrate mixture
were avoided. The GPS location at the beginning of the transect was recorded before
entering the water, at the bottom 90 m of transect tape was laid by divers (in the first few
transects only 30 m was laid), and the GPS location of the end of the transect was
recorded using a GPS device after exiting the water, again on the boat.
97
With ten days on the island, two transects in the morning and two transects in the
afternoon, forty transects were expected to be recorded. However, because the tide went
out in the afternoon, the fishing boats had to be grounded for the rest of the day, and data
collection was not possible in the afternoon. Only eighteen transect observations were
recorded and are shown in Figure 5.3a and Figure 5.3b below.
98
Figure 5.3a: Transect locations where substrate cover was recorded; image in natural color, bands 3, 2, and 1 in red, green, blue (2006 image inset).
99
Figure 5.3b: Locations of transects where substrate cover was recorded; Isodata classified image with 11 classes displayed (1999 image inset).
100
Image Selection
Five images over a fifteen year period between 1991 and 2006 were chosen for
the project. The open source software wxtide 32 (Hopper, 2006) was downloaded from
the internet and used to assess the tidal conditions at Makassar at the time of acquisition.
This was to assure the images were not taken at low tide when the reef flat is exposed
causing misclassification of that area as land. All other information is listed in Table 5.2
below.
Table 5.2: Specifications of Imagery Chosen
Table 5.2 Date Scanner
(TM/ ETM+)
Cost Acquisition Source Sun Azimuth
Sun Elevation
Sky Conditions & Wind Speed
Tide Height (Meters)
August 21, 1991 TM AU$1000
(US$800) Geoimage Pty Ltd, Qld, Australia 62.80 47.50 NA 0.55 m
August 23, 1992 TM AU$1000
(US$800) Geoimage Pty Ltd, Qld, Australia 64.10 47.80 NA 0.51 m
May 28, 1995 TM AU$1000
(US$800) Geoimage Pty Ltd, Qld, Australia 53.30 41.10 NA 0.84 m
September 20, 1999 ETM+ Free
download The Millennium Coral Project 74.19 60.61 NA 0.52 m
August 14, 2006 TM
US$350 (with OhioView discount)
US Geological Survey EROS Data Center, via OhioView Project
54.63 52.53 NA 0.72 m
101
Image Differencing
Change detection is the method whereby the differences between two images over
a given period of time are used to identify broad geographic trends and is the remote
sensing method used by managers to monitor compliance with policies such as use of
destructive fishing methods (potentially). Human impacts on the landscape (and
seascape) can be monitored much more quickly than on site surveys and specific areas for
coral reef rehabilitation can be targeted over a large area. Two different methods of
change detection have been identified by past research, post-classification and pre-
classification. In a post-classification image change detection, each image is classified
separately and then the two images are input into a before and after change matrix which
is used to compare the classes and give a statistical measure of change; in pre-
classification change detection, the change is based on pixel brightness values (BV) and
the nature of the change is then classified after the pixel subtraction (Jensen and Cowen,
1997).
The pixel brightness used in the image differencing of the marine environment
depends on a variety of factors, including bottom (benthic) cover, depth, and water
column turbidity. Because at depth the “optically dark marine habitats” such as algae and
corals tend to become spectrally similar, especially coral and seagrass (Zainal et al.,
1993; Holden and LeDrew, 1998b), the habitats in the waters of the Sabalana
Archipelago were not mapped for change using a post-classification change detection
method; rather, only the increase in brightness was pursued as a reflection of the increase
102 of spectrally bright rubble and sand and the decrease (loss or death) of spectrally dark
live coral.
Using one TM/ETM+ band (the blue band, band 1) the pre-classification change
detection method was chosen to compare the images (image differencing). This was done
by subtracting the brightness value of the pixels (on a scale from -255 representing full
blackness to 255 representing total whiteness of the Landsat TM and ETM+ scanners) of
the early image from the older one. A value of 0 was representative of no change,
negative values represented an increase in darkness, and positive values represented an
increase in brightness. For the purposes of this study, only positive values were mapped
because these values were indicative of an increase of brightening of live coral, which
happens with the death of symbiotic algae within the polyps (which is a result of blast
fishing, chemical fishing, or other bleaching events). The goal of this study is monitoring
the blast fishing behaviors of the fishermen as they spread the use of their destructive
methods from one area to another within the archipelago. This spread of behavior was
expected to be reflected in the progression of the brightening of pixels from one area to
another.
Registration
“’Registration’ is the process whereby one image is made to conform to another”
(Green et al, 2000 p. 99). Before registering the images however, they had to be of
uniform spatial dimensions. All images but one had 30 m pixels. The one image that had
28.5 m pixels (the 1999 image) was resized to 30 m to match the other images. The 1999
103 image was determined to be the most correct in terms of geography (latitude and
longitude) using Jafar’s hand-drawn map of Balobaloang Island (Ammarell, 1999, Map
2.2).
All images were registered to the 1999 image using six ground control points
(GCPs) from easily identifiable features as well as GPS locations recorded in the field.
Image-to-image registration to the 1999 image was done using visualized ground control
points and the pixel locator function rather than image-to-map because of the relative
ease and quickness. The GCPs recorded in the field using a handheld GPS device are
listed in Appendix A.
In working with a set of islands on a change detection project, it is assumed that
natural features will change over time. There is little man-made infrastructure that is
easily identifiable as would be the case in large urban areas such as road intersections.
Thus areas chosen for GCP identification included large mosques and school buildings
that are separated from coconut trees and have different reflectances from the
surrounding flora. A field cleared for soccer and camping also had a different reflectance
value than the trees and was used as a GCP. Also included in the GCP collection was the
research station location, though it was unclear whether the structure would be large
enough to be identified on the satellite imagery (in the end, it was not).
Six GCPs were selected using bright pixels in band 1 that stood out from the
surrounding vegetation. Three of the GCPs were on Balobaloang Island (two of which
were recorded in the field and included in Appendix A), one was on Sumanga’ Island,
104 one on Manukang Island, and one on Sarege Island to ensure a good distribution of GCPs
throughout the image (see Figure 2.1).
RMS errors were checked and found to be within acceptable parameters for all six
GCPs, at a value less than 0.10. All bands were warped according to these GCPs and,
upon warping, checked to ensure correct projection and spatial scales. All files were
linked to the 1999 image using the interactive linking function in ENVI and found to be
satisfactory in matching geographically.
Warping is the process where the images are made to geographically made to
match each other using the ground control points. Warping the images around the GCPs
using the 1999 image as the base also had the added benefit of transferring the chosen
projection, Universal Transverse Mercator (UTM) WGS84 Zone 50, to the output warped
images for each year. This projection was chosen because it is the most common in use
by computer programs (Green et al. 2000, p. 96) and because the research site in the
Sabalana Archipelago is near the equator and thus experiences little geographic warping
in UTM.
The nearest neighbor method of resampling was used because of the simplicity,
the “ability to preserve original [brightness] values in the unaltered scene”, and the
requirement of fewer GCPs than the other methods (Campbell, p. 306). The second order
polynomial was chosen because 6 GCPs were used, and recommended by Green et al. for
use with satellite imagery (2000, p. 101-102). After warping the images, the 1999 image
was subset to the area of interest (AOI), and then all images were subset using the extent
of that one image file as the base.
105
Atmospheric and Water Column Corrections
All five images were visualized to have much different radiometric characteristics
(i.e. some images were much brighter overall than other images). Similar to Holden et al.
(2004), correction for atmospheric attenuation was performed using histogram matching.
Because the 1999 image was much clearer than the raw images of 1991, 1992, and 1995,
and to better compare the images, the images were interactively stretched using a linear
stretch from 20 (minimum) to 120 (maximum). The stretched images were then saved
using the export stretch function on the histogram matching screen. This correction
method used two images together at the same time to produce images that more closely
match each other radiometrically. To more closely match the images in depth and
richness to the 1999 image that had been processed by the Millennium Coral Project and
to remove image brightening and striping in the older images experienced from scanner
aging (the TM scanner used was 22 years old as of 2006!), histogram matching was then
used.
According to Mumby et al. (1998), with coarse descriptive resolution as is used in
this project, the reef habitats are different enough so as not to require depth invariant
processing to correct for the darkening of water with increasing depth. The effects of
water column on spectral reflectance were assumed to be the same between all dates
because the location is far from urban areas that would cause increased turbidity
depending on a variety of environmental factors as described in Chapter 2. Thus, to
maintain consistency and not to produce undesired errors, no water column corrections
106 were used; because the water conditions of each date were unknown and because the area
is so far from land, water column corrections applied to each image individually were
deemed unnecessary and even counterproductive.
Change Detection via Image Differencing of the Blue Band 1
Before performing the image differencing, band 1 from each of the warped and
stretched images were compiled in one file using the layer stacking tool in ENVI. Then
using the “basic tools” and “band math”, the equation entered was [float(b1)]-[float(b2)],
where “b1” is band 1 from the most recent image and “b2” is band 1 from the older
image in the particular change investigated.
The transect observations were used in the locating areas where change detection
resulted from coral loss and were also used in determining the threshold for defining
change. Using the location to the west of Balobaloang Island previously identified by
fishermen as the site of daily blasting and later confirmed by diver observation, a
threshold was found that would identify the location where rubble was seen as a location
for change. First, the value of 10 was arbitrarily chosen and adjusted to conform with the
reef loss observation. To be conservative in the change detection image, the value of 12
was the threshold determined to capture change, but not overestimate it. This threshold
was used in all change images. The variation of difference values for the pixels within the
change images are listed in Table 5.3 below.
107
Using the “class color mapping” function in ENVI, values between 0 and 12 were
classified as no change and values greater than 12 were classified as change. This image
was then exported as an ArcView raster file for further processing in ArcGIS 9.0.
Table 5.3: Pixel Values for Change Images
Table 5.3 Maximum & minimum values for each change image, band 1 All images used 12 as the threshold for change
Change dates Minimum Value Maximum Value 1991-1992 0 75 1992-1995 0 81 1995-1999 0 79 1999-2006 0 78
End User Image Production
Call et al. (2003) showed that the infrared bands of Landsat TM can be used to
mask land features and clouds. In this project, using the “class color mapping” function in
ENVI as with the change images, and for each year band 7 was divided into two classes
to separate the islands and the clouds from the water, where the brightest values
represented everything not water. Again, all band 7s were exported as ArcView raster
files (though it was later found that exporting as Geotiff files better preserved the
geometry of the image for use in ArcGIS).
In ArcMap, the change images were reclassified: a value of 0 was given to pixels
with change values of 0-12 (representing the definition given of no change) and a value
108 of 1 was given to pixels with change values of 12-255 (representing the definition given
of change). Next, the raster was converted to a polygon file using the “conversion tool”
then “raster to polygon” functions in the toolbox.
The same transformations were done with the band 7 raster files for each year:
pixels with values of 255 were reclassed to 1 (representing land and cloud), and 0
(representing water). Again the reclassed band 7s were converted into polygon files.
After conversion into polygon shapefiles, the increases in brightness that resulted
from cloud cover or beach expansion were deleted using the “erase” function in ArcMap
toolbox. Band 7 from the later date of the two change images was used to erase the
brightness increases due to cloud or land (e.g., in the 1991-1992 change image, band 7
from 1992 was used to erase the brightness increases due to cloud and land).
Finally, using the natural color (blue band 1, green band 2, red band 3) 2006
image, the reef extent was traced at roughly a 22 meter depth (12 fathoms according to
the depth chart in Figure 3.1). Using the editor tool in ArcMap, a shapefile was created of
the reef extent. Also using the 2006 reclassified polygon of band 7, the islands were
selected and saved as a shapefile. All elements were then combined to create Figure 5.4
below.
109
Figure 5.4: Change detection map of reef brightness increase in the Sabalana Archipelago between 1991 and 2006 (map produced by author; data sources: 1991, 1992, and 1995 from Geoimage Pty Ltd., Queensland, Australia; 1999 from the Millennium Coral Project; 2006 from the US Geological Survey EROS Data Center).
110
5.4 Results and Discussion
The change image produced in Figure 5.4 shows change on a large scale that
reflects the accounts of villagers of Balobaloang Island. In Hapsari’s video (2008) the
fishermen tell of decreasing fish catches forcing them to travel further distances for their
subsistence fishing, stories which were also heard while conducting field research for this
project during the summer of 2006.
The reef cover reflectance was found to have increased in brightness over the
fifteen year time period covered in this project. Though it is unclear exactly which DFP
method caused the brightness increase, blast or chemical fishing (as both have reported in
the area), or what was the nature of the reef change (coral to rubble, seagrass to sand,
etc.), the extent of the damage is troubling. The change image can be interpreted to be
loss of seagrass habitat when it is near shore and loss of coral habitat when lining the
edge of the reef on the reef crest because in situ observations found these to be the
substrate cover common in the areas where change was found.
Most troubling is the brightness increases in small patches in reef crests east and
northeast of Sumanga’ Island and north of Sabaru Island as well as the area just to the
west of Balobaloang Island between 1992 and 1995 which shows that live coral loss is
indeed reflected in the archive of satellite imagery. However, because of the large area of
increase in brightness between Balobaloang Island and Sabaru Island between 1991 and
1992, and because the first change was not initially surrounding Sumanga’ Island, it is
more difficult to say that this loss of live coral is shown to start around Sumanga’ Island
111 and spread to the other areas. According to Ammarell (personal communication) who
was conducting research during the 1991-1992 time period, there was bombing off the
south side of Balobaloang Island, and there were healthy reefs to the west of the island.
Along these same lines, it is good to note that the reef crest on the north side of
Balobaloang Island has experienced much less change (increase in brightness) than the
reef crests of the other islands. This is a hopeful sign and points to the people of
Balobaloang Island being effective in their efforts to protect their reefs.
Because very little change was detected in the Taka Luara fishing grounds, it is
hard to say that the effects of chemical fishing known to exist in the area is reflected in
the satellite imagery archive. It is possible that the fishing grounds of Taka Luara are too
deep for any meaningful change detection to be possible. The small patches that were
shown within Taka Luara should be visited to investigate whether or not the change
detected is meaningful.
Though the progress of the spread of damage throughout the area of interest is not
immediately visible in the change image, it is clear that most of the coral reef damage is
in the area surrounding Sumanga’ Island, particularly concentrated in the reef crest east
and northeast of the island. Also of note is the dramatic brightness increase of the reef
crest north of Sabaru Island; it is so clear that it is focused on the crest that it is possible
to see the edge of the reef from the change detection image. This is especially troubling
because it is not the people from Sabaru Island that are causing the loss if it is indeed sue
to blast or chemical fishing, but it has been caused by those from other islands. The
brightness increase is unlikely due to wave action, with the waves breaking in that area,
112 because it is not continuous throughout the reef crest and only appears in patches as is
expected with DFP use.
Because Figure 5.4 points to damage concentrated between 1999 and 2006, a
more detailed examination using the same protocol and two additional images from 2002
and 2004 is recommended. A visual examination of Figure 5.4 shows that the reefs have
experienced great loss over the 1991-2006 time period, consistent with the fact that this is
the greatest time difference between the images with seven years. Furthermore the
findings are not necessarily consistent with Steyn’s (2005) conclusion that the reefs
around Balobaloang are in good condition and Burke’s (2002) classification of the area in
Figure 4.1 as being under a “low threat” from destructive fishing.
113
CHAPTER 6. CONCLUSIONS AND RECOMMENDATIONS
The destructive fishing practices of blast and chemical fishing known to have
been used in the study area within this paper have had a large impact on the reefs
surrounding Balobaloang Village over the fifteen year period of study. With the patchy
increases in brightness that were expected reflecting reef loss from blast and chemical
fishing, both the TM and ETM+ scanners aboard the Landsat satellites were shown to be
useful in reef status monitoring. The reef damage mapped using pixel brightness increase
in increments between 1991 and 2006 showed brightness increases most extensively in
the reef crest on the east and northeast side of Sumanga’ Island. This finding reflects the
exhaustion of resources by blast fishermen living on that island as described in Hapsari
(2008). Heaviest damage was seen in the period between 1999 and 2006, the longest time
period between two images within the set, suggesting a need to more finely investigate
the period with additional satellite imagery within that period, perhaps additional imagery
from 2002 and 2004. Such brightness increase in the reef crests (see Figure 6.1 for
definition of this term) was also seen around other islands as well as in an extensive area
to the west of Balobaloang Island. This area west of Balobaloang Island is known to have
experienced almost daily use of blast fishing and is where rubble “killing fields” were
observed by the author. The effects in the Taka Luara fishing grounds said to be the area
where chemical fishing has been used since about 2003 were indeterminable because of
114 depth, though a small number of pixels identifying change should be visited for further
investigation.
Figure 6.1: Outline of reef zonation
(source: http://animals.howstuffworks.com/marine-life/coral-reef.htm/printable).
However, the nature of the reef changes cannot be determined from satellite
imagery using pre-classification image differencing as was done in this study. Because of
time and budget limitations, the study goal was only to identify areas of change and not
the nature of that change. Some of the areas identified may have resulted from loss of
seagrass, which are areas more likely to be close to shore. Other areas, such as reef crests,
are easily identified visually in the change image Figure 5.4 such as those around
Sumanga’ Island, Lesser Balobaloang Island, and Sabaru Island. This was not seen in the
reef crests around Balobaloang Island, perhaps because the people are better stewards of
their resources and/or because they are better able to protect from outside predatory
115 fishermen using DFPs. The loss in the reef crests can be interpreted as loss of live coral
reef because of the bleaching that occurs after expulsion of symbiotic zooxanthellae from
the sensitive polyps after blasting.
The Landsat TM and ETM+ data were shown to be useful in detecting change in
reef habitat and are a cost effective resource for managers looking to monitor reef health
and identify areas for law enforcement patrols. Large areas found to have experienced a
spectral brightening can be identified for investigation for presence of rubble. For a more
detailed mapping of the nature of the change, extensive in situ observations must be
made, dramatically increasing the cost of the project. Furthermore, research needs to be
done for the development of at “spectrally based bleaching index” (Elvidge et al., 2004).
Because of the tides of the time of year and month within the present study, only
the time between 7 a.m. and roughly 1 p.m. was available for recording transect
observations on the reef, and the duration of field work was limited to eight days. In order
to record enough transects to perform a post-classification change detection and accuracy
assessment necessary for a study of the nature of the change, two to three months of field
research is recommended. Thus the pre-classification method used in this study can be
relatively cost effective for use in reef management programs.
116
6.1 Practical Applications of This Research
Burke et al. (2002, p. 64) noted about Southeast Asian reef management that
“managers and communities are not receiving the information they need to make sound
management decisions” and that “remotely sensed data are most valuable when coupled
with well-designed in situ monitoring, including repeat monitoring of permanently
marked stations.”
Such programs include both education of reef users (particularly alternative
employment), enforcement of reef protection laws, and rehabilitation of the living coral
reefs. Together with local communities, education programs can be used as a first step in
a reef rehabilitation program. Both local residents and those using the destructive fishing
practices need to be in partnership with the managers, in a community based incentive
program, for it to be effective. One program begun in January 2007 in the study site is the
second Coral Reef Rehabilitation and Management Program in Indonesia (COREMAP II)
(April, 2008), the first of which was in western Indonesia. Among the many activities of
this program, local fishermen from Balobaloang Island (one of whom was the dive boat
captain for the field work portion of this study) monitor destructive fishing activities in
the reefs around their island, children are taught about the value of the coral reefs, and
fishermen who use the unsustainable DFPs are educated about alternative livelihoods.
The area is headed in the right direction for preservation and rehabilitation of the
reef resources; however, there are concerns about corruption related to the program itself.
These concerns involve high level Pangkep Regency officials on the main Island of
117 Sulawesi allowing access to the sites, local police, other law enforcement officials, and
local politicians, many of whom have been paid off in the past to ignore illegal
destructive fishing activities and now expect to be paid extra to side with the
conservationists. These concerns may be real or imagined. At this time, it is more
imperative than ever for the conscientious leaders and members of the program (as well
as future members), especially those at the local level, to act to stop the corruption from
within. According to Pauly (2008) the long term solution to fisheries in distress is to limit
entry to traditional small scale fisheries; as Berrill (1997, p. 86) wrote, “economically,
open-access fishing is madness.” For such programs to be effective, grassroots pressure
from those affected is necessary, and without which the program will fail. Finally, it is
only when such programs are in full swing that reef rehabilitation efforts should even be
considered.
6.2 Challenges and Other Things to Take into Account
With the study site being so isolated, and the time limitation of ten days on site,
preplanning was essential. Communication with the main island of Sulawesi and the city
of Makassar is impossible. Though there was a satellite phone on the island, it was not
working during our stay. Furthermore, the cargo ships do not carry communications
equipment, so even a boat docked offshore must be contacted via smaller boat (jolor).
118 Supplies limiting the expedition include gas (Indonesian: benzin) for the compressor to
fill the SCUBA tanks as well as food.
To be able to accurately locate pixels for study from the field map, it was
necessary to have a version of the remote sensing or GIS software in the field. There was
no internet connection to obtain information about weather forecasts to pre-plan for
which sites could be visited on a given day. For example, the Taka Luara fishing grounds
were visited on the second to last day in the field because the entire time was far too
windy before that. After a one hour hazardous trip though large waves and high winds to
the location, conditions were unfit to safely enter the water, and the substrate was never
observed. The weather conditions would most likely be better another month or two later
in the summer, such as April-May or October-November during the dry season.
Permanent transects should be established to observe the seasonal changes in the fisheries
as is seen in anchovy populations, for example.
Other challenges involved the cultural differences from island to island. Though
Sumanga’ Island is where the blast fishermen come from, I was not able to travel there to
conduct interviews or survey the reef. Because Balobaloang Island was the location of the
research station and the people are accustomed to researchers from Ohio University and
Hasanuddin University visiting the island, they had become quite friendly and
welcoming. However, because the people of Sumanga’ Island were the ones participating
in the illegal activity and because the police on the island were corrupt (according to local
accounts), the issue of my personal safety in researching the illegal activities was
questionable. Therefore all information on local accounts of the problem is based only on
119 the accounts of Balobaloang residents, and all other accounts are from Hapsari’s video
(2008).
The need to be culturally sensitive in the study site is essential when doing
research as a visitor. Being a woman working on an island where the women dress
conservatively by American standards (though moderate by Indonesian standards; e.g.
most women do not wear headscarves or even long sleeved shirts), wearing even a one
piece swimsuit could cause misunderstanding and make the locals uncomfortable.
Though I wore a full length, black wetsuit over my swimsuit out of water, it was usually
too hot to keep on the top half while on the dive boat. Wearing a full wetsuit while out of
water being uncomfortable, I had to make sure to always use a sarong or other type of
cover-up over my shoulders and top half of my body (also an essential for sun
protection). This is the reality of being a foreign woman working in marine environment
in a Muslim country.
Having local contacts to be able to assist in arranging a dive boat (really a
modified fishing boat with a motor), fishermen knowledgeable of the local reefs and the
conditions, and colleagues from Hasanuddin University were of immeasurable
significance. Without these people, research in the Sabalana Archipelago is much more
difficult.
This study does not include a count of the types and numbers of fish caught nor
does it address the problem of corruption. Though it addresses the spread of damage from
one location to other locations, it does not address the background causes and
personalities involved in perpetuating the activities. The politics and corruption
120 surrounding the protection of fishermen using destructive fishing practices were not
addressed in this paper, as the purpose was mainly to identify geographic locations,
extent, and spread of reef damage.
6.3 Suggestions for Future Work
During the time this paper was being written, another extremely significant and
germane study was published. On July 10, 2008 the first ever global assessment of reef-
building (scleractinian) corals was published in the journal Science Express (Carpenter et
al., 2008). The research group, composed of 33 scientists from all over the world, joined
with the Global Marine Species Assessment (GMSA) to assess the status reef-building
corals according to International Union for Conservation of Nature (IUCN) Red List
criteria. This list covers all threatened species in ecosystems worldwide. Carpenter et al.
(2008) found 32.8% of reef-building corals (845 species were examined) to be in danger
of extinction from global climate change as well as the variety of anthropogenic factors,
and that “the extinction risk of corals has increased dramatically over the past decade” (p.
2). The Coral Triangle, which includes the study site in this paper, was found to have the
“highest proportion of Vulnerable and Near Threatened species,” with 50%-60% of
species. As Figure 2.2 shows, the highest number of these corals is in the Coral Triangle,
at over 500 species. The authors warned that “if corals cannot adapt, the cascading effects
of the functional loss of reef ecosystems will threaten the geologic structure of reefs and
121 their coastal protection function, and have huge economic effects on food security for
hundreds of millions of people dependent on reef fish” (p.3).
Studies such as the one mentioned above have been giving numbers for threatened
reefs, coral, fish, etc. for a number of years. After reading numerous articles for this
paper, the numbers quickly blend into each other and turn into a kind of white noise. The
challenge for the reader and for conservationists is making these numbers understandable
for the public. These numbers are nice for science, but if they cannot be used to create
change in the community that is causing the problems, they are useless. Where such
studies fall short is that they area so general in the findings that they become
overwhelming. Fortunately, Carpenter et al. (2008) broke down their findings regionally
and showed how the Coral Triangle compares to the rest of the world in terms of percent
of threatened reef-building coral species. More detailed research on the causes of the
decline in species is needed in order to target programs for protection and rehabilitation
of coral reefs.
The fisheries of the reefs need to be monitored more closely such as a count of the
numbers and types of fish caught by the bombers as was done by Fox and Erdmann
(2000) in North Sulawesi. Because of the close relationship between corals and fish, the
numbers and types of fish recorded in a rapid assessment is a reflection of the health of
the reef itself. Reef Check has been doing an excellent job of documenting fisheries
worldwide, however permanent transects need to be geographically documented and
monitored regularly. Researchers must return to the same sites at different times of the
year because of changing fish populations throughout the year and migration (such as is
122 seen with anchovies). In the study area of the Sabalana Archipelago, the manta tow
method would be a cost effective method of documentation, where a snorkeler is towed
behind a boat at a certain speed, stopping at a certain regular interval to record
observations on a clipboard atop the tow handle.
The economic histories of the islands of the Sabalana Archipelago should be
recorded through interviews of locals. This may shed light on any correlation with DFP
use and how and to what extent people of the island have benefited from the greed of the
fishermen. Furthermore, there is the question of whether or not the island has suffered as
a result of habitat destruction. A study of the economics done using the parameters of the
Socio-economic Monitoring (SocMon) program is recommended
(http://www.reefbase.org/socmon/). Jamaluddin Jompa, a marine biologist at UNHAS
who has visited the area, estimates that if the intensity of cyanide use and bombing does
not decrease within five to ten years the reefs will not be able to recover for a long time,
as much as fifty years (Hapsari, 2008). As of late 2006 there was not enough fish left to
support one fisherman of Balobaloang Island, and he had to sell his boat (Hapsari, 2008);
two years earlier he had been able to pay off his boat with the fish he caught. There is
some anecdotal evidence that detonators and blasting caps have become difficult to
obtain because of government anti-terror activities and that blast fishing has dropped a bit
because of this (Hapsari, 2008).
123
6.4 Follow the Supply Chain
The most important recommendation is to increase public awareness of the
impacts of consumer behavior (both locally and internationally) through outreach
programs. Local islanders need to know the value of their reefs and that they area not
inexhaustible (as Chozin [2008] found, the people of the Spermonde Archipelago near
Makassar think the reefs cannot be destroyed), tourists need to understand the fish and
lobster eaten at local hotels may have been caught using DFPs, mainland Asians who are
consumers of Indonesian fish (especially Chinese and Japanese) need to know if the live
fish in their aquariums used for food have been caught using DFPs, and Americans need
to know if the ornamental fish like clownfish that live only in the Pacific Ocean have
been caught using DFPs (see Sale, 2002 for a comprehensive review of the international
live fish trade). [What a wonderful use of the Disney character Nemo from Finding Nemo
– to speak for the reefs like the Lorax speaks for the trees!] To convince people that the
fish they eat and use in their aquariums are caught in unsustainable ways, research needs
to be done tracing the fish back through the supply chain to the source. In addition to
addressing fishing methods, mooring buoys need to be established so that anchors do not
damage the reefs, as McManus (1997) noted that the use of grapple hook anchors needs
to be changed.
Together with a public awareness campaign, this research is so desperately
needed. However difficult it may be, considering the stakeholders may be dangerous
characters if they feel their livelihood is threatened, the academic and NGO community
124 must be more proactive. Supply chain research would provide the link between the
academic community and the public to begin to create the change to save the coral reefs
of Indonesia and Southeast Asia in general.
6.5 Take Advantage of the Free Landsat Archive
Since this project was done, the US Geological Survey announced that it will be
releasing all Landsat imagery for free download, thanks to those who put so much work
into the OhioView and AmericaView projects (Lein, personal communication). The
imagery will be released in stages, and the entire archive is expected to be available as of
February 2009 (Beck & Headley, 2008). This new development is an exciting
opportunity for students and researchers to more accurately monitor the health of coral
reefs, and now there is no longer a need to rely on mere estimates. It is now practical to
map all of the reefs around Southeast Asia using the Landsat archive and a handful of
dedicated imagery analysts.
125
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140
APPENDIX A. RAW DATA USED IN CHAPTER 5
Satellite Imagery Profiles
a. Satellite imagery profile (all are Landsat 5 TM except for the 1999 Landsat 7 ETM+ image; all are path 114, row 65; Universal Transverse Mercator (UTM) projection Zone 50S datum WGS84; Alice Springs, Australia was the receiving station to which all images were downloaded),
b. Tidal profiles of nearest point available in WXTide32 version 4.6 (Hopper, 2006) open source software (nearest station is Makasak [sic], located at E 119°24.00', S 5°9.00'), and
c. Astronomical profiles for those dates, calculated from the US Naval Observatory website (http://aa.usno.navy.mil/data/docs/RS_OneDay.php):
1. August 21, 1991 – time of acquisition 13:34pm
a. Bought from Geoimage Pty Ltd in Queensland Australia Information from ACRES Geoscience Australia Digital Catalogue Landsat 5 TM ID # 105011406519910821013438 Sun azimuth 62.80° Sun elevation 47.50°
b. Profile from WXTide32v.4.6: High tide 03:48, 1.1m Low tide 18:27, 0.3m Tide at acquisition 0.55m First quarter moon
c. Profile from US Naval Observatory SUN Begin civil twilight 05:49 Sunrise 06:10 Sun transit 12:08 Sunset 18:06 End civil twilight 18:27 MOON Moonrise 14:01 on preceding day Moonset 02:50 Moonrise 14:51 Moon transit 21:15 Moonset 03:37 on following day Phase of the Moon on 21 August: waxing gibbous with 84% of the Moon's visible disk illuminated. First quarter Moon on 17 August 1991 at 13:01 (Universal Time + 8h).
141
2. August 23, 1992 (alternate for 1993 image that was not available) – time of acquisition 13:33pm
a. Bought from Geoimage Pty Ltd in Queensland Australia Information from ACRES Geoscience Australia Digital Catalogue Landsat 5 TM ID # 105011406519920823013328 Sun azimuth 64.10° Sun elevation 47.80°
b. Profile from WXTide32v.4.6: High tide 03:03, 1.0m Low tide 17:50, 0.3m Tide at acquisition 0.51m Last quarter moon
c. Profile from US Naval Observatory SUN Begin civil twilight 05:48 Sunrise 06:09 Sun transit 12:07 Sunset 18:05 End civil twilight 18:27 MOON Moonset 12:16 on preceding day Moonrise 01:10 Moon transit 07:12 Moonset 13:14 Moonrise 02:09 on following day Phase of the Moon on 23 August: waning crescent with 31% of the Moon's visible disk illuminated. Last quarter Moon on 21 August 1992 at 18:02 (Universal Time + 8h).
First choice image that was unavailable:
Information from ACRES Geoscience Australia Digital Catalogue October 13, 1993, 13:33, Landsat 5 TM ID # 105011406519931013013316
Sun azimuth 93.00°, sun elevation 56.30° Low tide 17:24 0.5m, High tide 23:15 0.9m, Tide at fly over 0.61m moon transit 09:40, last quarter moon
142
3. May 28, 1995 – time of acquisition 13:18 a. Bought from Geoimage Pty Ltd in Queensland Australia
Information from ACRES Geoscience Australia Digital Catalogue Landsat 5 TM ID # 105011406519950528011804 Sun azimuth 53.30° Sun elevation 41.10°
b. Profile from WXTide32v.4.6: High tide 08:44, 1.1m Low tide 20:49, 0.3m Tide at acquisition 0.84m Last quarter moon
c. Profile from US Naval Observatory SUN Begin civil twilight 05:46 Sunrise 06:08 Sun transit 12:02 Sunset 17:55 End civil twilight 18:17 MOON Moonset 16:24 on preceding day Moonrise 05:03 Moon transit 11:06 Moonset 17:09 Moonrise 05:51 on following day Phase of the Moon on 28 May: waning crescent with 1% of the Moon's visible disk illuminated. New Moon on 29 May 1995 at 17:27 (Universal Time + 8h).
143
4. September 20, 1999 – time of acquisition 13:35 a. Downloaded from Millennium Corals Website
Information from Institute for Marine Remote Sensing (IMaRS) metadata Landsat 7 ETM+ ID # 7114065009926350 Sun azimuth 74.19° Sun elevation 60.61°
b. Profile from WXTide32v.4.6: High tide 01:29, 1.0m Low tide 17:38, 0.4m Tide at estimated time of acquisition 0.52m First quarter moon
c. Profile from US Naval Observatory SUN Begin civil twilight 05:35 Sunrise 05:56 Sun transit 11:58 Sunset 18:01 End civil twilight 18:22 MOON Moonrise 12:51 on preceding day Moonset 01:34 Moonrise 13:40 Moon transit 20:02 Moonset 02:24 on following day Phase of the Moon on 20 September: waxing gibbous with 72% of the Moon's visible disk illuminated. First quarter Moon on 18 September 1999 at 04:06 (Universal Time + 8h).
144
5. August 14, 2006 – time of acquisition 14:03 a. Bought from USGS using OhioView discount
Information from USGS Glovis Visualizer Metadata Landsat 5 TM ID # 5114065000622610 Sun azimuth 54.63° Sun elevation 52.53°
b. Profile from WXTide32v.4.6: High tide 07:23, 0.9m Low tide 20:21, 0.5m Tide at estimated time of acquisition 0.72m Full moon
c. Profile from US Naval Observatory
SUN Begin civil twilight 05:51 Sunrise 06:13 Sun transit 12:09 Sunset 18:06 End civil twilight 18:28 MOON Moonrise 21:45 on preceding day Moon transit 03:53 Moonset 09:59 Moonrise 22:39 Moonset 10:47 on following day Phase of the Moon on 14 August: waning gibbous with 71% of the Moon's visible disk illuminated. Last quarter Moon on 16 August 2006 at 09:51 (Universal Time + 8h).
145
Locations of GPS Control Points to Register Images
Waypoints taken by Andi “Edow” Maddusila on September 21 and 22, 2007 Balobaloang Island Field corners S6° 35’ 38.1”, E118° 51’ 40.92”
S6° 35’ 38.34”, E118° 51’ 42.96”
S6° 35’ 35.94”, E118° 51’ 43.62”
S6° 35’ 35.16”, E118° 52’ 42.00”
Field center S6° 35’ 36.96”, E118° 51’ 42.36”
Mosque S6° 35’ 43.26”, E118° 51’ 36.60”
Research S6° 35’ 42.42”, E118° 52’ 2.94” Station
School S6° 35’ 39.42”, E118° 51’ 37.80”
Sabaru Island Field corners S6° 34’ 36.12”, E118° 50’ 19.44”
S6° 34’ 37.98”, E118° 50’ 18.66”
S6° 34’ 38.94”, E118° 50’ 21.12”
S6° 34’ 37.08”, E118° 50’ 21.66”
Field center S6° 34’ 38.10”, E118° 50’ 20.22”
Mosque S6° 34’ 27.48”, E118° 50’ 19.80”
SD S6° 34’ 28.14” E118° 50’ 21.18”
146
APPENDIX B. RAW TRANSECT DATA
Collected for baseline data for future research “Field map” refers to the classified map created using ENVI Isodata unsupervised classification of September 20, 1999 Landsat image downloaded from Millennium Corals Website (dca = dead coral algae) Obs 1 – Saturday, June 10, 2006, 7:51 a.m. Fishermen say this area has been blasted every day until a month ago Start: S6° 36’ 04.3”, E118° 51’ 28.9”; depth 9.2 m End: S6° 36’ 04.6”, E118° 51’ 27.6”; Dive started 9:00 a.m. Strong northwest current Location about 250 m offshore Purple on field map
Substrate cover observed: sand and rubble mix Obs 2 -- Sunday, June 11, 2006, 8:00 a.m. (Landsat satellite flyover today) Start: S6° 34’ 56.3”, E118° 51’ 33.5”; depth 3.9 m (high tide) End: S6° 34’ 56.3”, E118° 51’ 32.7” Conditions, about 1 m waves Green on field map
Substrate cover observed: sand, rubble, and dead coral algae mix Obs – Sunday, June 11, 2006 Waves too high to dive Passed through point S6° 34’ 53.5”, E118° 51’ 17.3” Dark brown on field map
Substrate cover observed: sandy and shallow Obs 3 – Sunday, June 11, 2006, 9:20 a.m. Point: S6° 35’ 15.2”, E118° 51’ 05.4”; depth 5 m with 1 m waves Red on field map
Substrate cover observed: all rubble with a few coral heads
147 Obs 4 – Monday, June 12, 2006
Conditions: overcast with drizzle, strong current from east to west toward end of transect Start: S6° 35’ 31.0”, E118° 52’ 16.2”; depth 5 m Midpoint: S6° 35’ 31.8”, E118° 52’ 15.7” Midpoint: S6° 35’ 32.5”, E118° 52’ 14.7” End: S6° 35’ 32.6”, E118° 52’ 13.8’’ 1st half light blue (teal); 2nd half light brown on field map Substrate cover observed: sand to the north of start point 1st 30m: dca 60%, healthy coral 30%, sand 10% 2nd 30m: dca 50%, healthy coral 40%, sand 10% 3rd 30m: not recorded – current blew observer off transect
Obs 5 – Monday, June 12, 2006, 5:26 p.m. Walking observations of intertidal zone at low tide Start: S6° 35’ 22.6”, E118° 51’ 48.2” Midpoint: S6° 35’ 21.2”, E118° 51’ 49.5”
End: S6° 35’ 17.8”, E118° 51’ 50.8” Starts mixed (dark brown, light brown, purple); then becomes mostly light purple on field map Substrate cover observed: 1st line seagrass 2nd line mostly rubble, rock, and sand (less seagrass) To the north of endpoint, 50 m of live coral Acropora (no waypoint recorded because I didn’t want to walk on top of the live coral)
Obs 6 – Tuesday, June 13, 2006, 8:00 a.m. Start: S6° 36’ 07.5”, E118° 50’ 56.4”; depth 12 m (sea darker blue) Strong wind, current to the northwest Peach color on field map
Substrate cover observed: Sand {no photos, observation from surface only, dive abandoned because of strong current}
Obs 7 -- Tuesday, June 13, 2006, 9:21 a.m. Start: S6° 35’ 47.5”, E118° 51’ 18.1”; depth 1 m at high tide End: S6° 35’ 43.7”, E118° 51’ 19.1”
Light blue on field map Substrate cover observed: live coral at beginning and turned to rubble at end of transect
148 Obs 8 – Tuesday, June 13, 2006, 9:30 a.m. Start: S6° 35’ 52.1”, E118° 51’ 40.4”; near shore, depth 2 m Start first third dark purple, then light brown on field map
Substrate cover observed: 1st 30m 70% live coral, 20% rocks 2nd 30m 50% rocks, 20% seagrass, 10% live coral
Obs 9 – Tuesday, June 13, 2006, 5:30 p.m. - 5:45 p.m. Walk on the pier on the south side of the island
Start of pier: S6° 35’ 47.7”, E118° 51’ 37.5” End of pier: S6° 35’ 53.8”, E118° 51’ 34.7” Undetermined color on field map (mix of many colors; mostly light brown toward end of pier) Substrate cover observed: 100% seagrass around the wooden pier
Obs 10 – Wednesday, June 14, 2006 Trip out to Taka Luara fishing grounds (south of Balobaloang Island) Start: S6° 40’ 10.0”, E118° 49’ 23.6”, depth 12 m End: S6° 41’ 23.2”, E118, 48’, 47.4” {turn around point} Waves too high to get into water (~2.5-3m), no snorkel, no dive, no photos
Purple on field map Substrate cover observed: No observations because of unsafe conditions Obs 11 – Wednesday, June 14, 2006 South side of Balobaloang Island, east of the pier
Artificial sandbar around 30m-40m long, built for locals for agar cultivation in the past, no photos
Start: S6° 35’ 58.8”, E118° 51’ 54.7” Light teal on field map, almost on the border with light brown pixels Substrate cover observed: sand and rock, Obs 12 – Wednesday, June 14, 2006 Dead reef, naturally pushed by current into bump, no photos Start: S6° 35’ 54.9”, E118° 51’ 39.2” Light brown (on edge with light purple) on field map Substrate cover observed: Dead coral
149 Obs 13 – Wednesday, June 14, 2006 Near shore snorkel Start: S6° 35’ 30.3”, E118° 52’ 09.0”, depth 1~1.5 m at high tide End: S6° 35’ 31.4”, E118° 52’ 05.4”
Light purple on field map Substrate cover observed: 65% rock, 10% sand & rubble, 20% seagrass (mixed, not dense, see photo 075), 5% healthy coral
Obs 14 – Thursday, June 15, 2006 Sunny day, with a few clouds, windy, 0.5 m waves Used to be coral and now blasted (according to fishermen)
Start: S6° 35’ 22.3”, E118° 51’ 04.5”, depth 4.5 m at high tide End: S6° 35’ 20.1”, E118° 51’ 05.3” Start and end is red, passing through peach, on field map Substrate observed: all rubble with 10% live coral, including 60 m to the north and 30 m to the south of transect
Obs 15 – Thursday, June 15, 2006 Waves too rough for snorkel observations, sunny & 15mph wind from SE Start: S6° 35’ 48.7”, E118° 50’ 53.0”, depth 8.5 m at high tide Teal (light blue) on field map Substrate observed: No observations because of unsafe conditions Obs 16 – Thursday, June 15, 2006 Waves too rough for snorkel observation, sunny & 15mph wind from SE Start: S6° 36’ 10.6”, E118° 51’ 33.9”, depth 9 m at high tide, 2 m waves
Peach on field map Substrate observed: No observations because of unsafe conditions Obs 17 – Thursday, June 15, 2006 Start: S6° 35’ 04.0”, E118° 51’ 26.5” Snorkeled 60 m to the south Dark brown on field map Substrate observed: 1st 30m 20% seagrass & rubble, 70% rocks, 10% live coral 2nd 30m the same
150 Obs 18 – Thursday, June 15, 2006, 10:10 a.m. Start: 6° 35’ 00.3”, E118° 51’ 40.4”, Depth 9.5 m rising to 6 m End: 6° 34’ 57.9”, E118° 51’ 37.7” Teal 1st third, light brown, then green on field map Substrate observed: 1st 30m 95% live coral, 5% rock 2nd 30m same 3rd 30m 75% live coral, 25% rock (probably sandy patches too) Sandy bottom on other side of start * Old Dutch Harbor Location S6° 35’ 52.6”, E118° 51’ 32.6”
151
APPENDIX C. REEF BALL INFORMATION
GPS location taken Monday June 12, 2006 S6° 35’ 31.2”, E118° 52’ 16.2”; depth 5.4m Photos
(a) (b)
(c)
(a) Top left: the reef ball built by Rita Steyn in 2004. (b) Top right: the same ball in 2006 (the small piece has been buried in sand). (c) Bottom: the new ball built in 2004 and put in the water by my team in 2006.
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