Project report 2002 - Aders' duiker in ASF.pdf

A CONSERVATION AND RECOVERY PLAN FOR THE

ADERS’ DUIKER CEPHALOPHUS ADERSI IN ARABUKO-

SOKOKE FOREST, KENYA

ERUSTUS M. KANGA

KENYA WILDLIFE SERVICE

OCTOBER 2002

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TABLE OF CONTENTS

1.0 INTRODUCTION ...................................................................................................4 Objectives: .....................................................................................................................6

2.0 STUDY AREA ........................................................................................................7

Figure 1: Location of Arabuko-Sokoke Forest ................................................................8 Figure 2: General Vegetation Types in Arabuko-Sokoke Forest....................................10

3.0 MATERIALS AND METHODS............................................................................11

Figure 3: Shape of the drive area showing how nets were set in before a drive took place......................................................................................................................................12 Identification of an In-situ breeding site........................................................................14

4.0 RESULTS AND DISCUSSION.............................................................................15

Mini-antelopes Population Size and Density Estimates. ................................................15 Disturbance in the forest ...............................................................................................16

5.0 Conclusions and Recommendations .......................................................................25

Actions for Conservation and Recovery of Aders’ duiker .............................................25 Education and awareness...........................................................................................26 InSitu Captive breeding.............................................................................................28 Lobby for enlargement of the current Nature Reserve area ........................................28 Strengthen law enforcement ......................................................................................28 Support in-come generating activities........................................................................28 Research and Monitoring...........................................................................................29

6.0 LITERATURE CITED. .........................................................................................31



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ACKNOWLEDGEMENT

This report is the product of generous support from various individuals, whose help I have

the pleasure to acknowledge. Full financial support came from Paignton Zoo (UK).

I express profound gratitude to Dr Amy Plowman of Paignton Zoo (UK) who was

instrumental in organizing for the grant as well as its disbursement. She was very

supportive during times of needs and I say a big thankyou to her for being mindful of the

conservation of African duikers. Extra thanks go to Eston Murithi, my field assistant and

in-charge logistics support during data collection and report draft preparation. The team of

the local duiker drivers, led by Willington Kombe, were valuable and their support is

memorable. To all other individuals who assisted in different ways, especially the staff of

Kenya Wildlife Services (KWS), Forest Department (FD), and Kenya Forest Research

Institutes (KEFRI) at Gede Forest Station, I say thank you to you all.



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1.0 INTRODUCTION

Duikers are antelopes of the subfamily Cephalophinae, within the family Bovidae. The

Cephalophinae is only found in Sub-Saharan Africa and comprises of two genera;

Sylvicapra (1 species) and Cephalophus (17 species) (Kingdon, 1982; 1997). Taxonomy of

the Cephalophus is still controversial (Kingdon, 1982; 1997; Newing, 1994). For example,

the Hervey’s duiker C. harveyi hybridize with the Natal red duiker C. natalensis and

Peter’s duiker C. calliygus in the regions of Dar es salaam Tanzania and Mau forest in

Kenya respectively (Kingdon, 1997). There are possibilities that some recognized

subspecies of duikers might be distinct species while species that are currently hybridizing

may be subspecies.

Most duikers live sympatrically and those inhabiting dry thickets, alpine scree and swamps

resemble those living in true forests in terms of the basic body morphology (Kingdon,

1982 and 1997). However, all species are generally of different body sizes, which is a

possible source of their ecological separation (Kingdon, 1982 and 1997; Newing, 1994).

Other potential causes of ecological separations include activity patterns (either diurnal,

nocturnal or both), variable social systems, habitat and diet specialization. There is great

variability in their average body weight. The smallest is the blue duiker weighing about 3.5

kg, while the heaviest is the Jentink’s duiker weighing about 80 kg. This variation in body

size enables them to utilize different diet types (Hofmann, 1973), make use of different

habitats and avoid predation.

Most indigenous forests in Africa have at least one species of duiker in them. The

existence of 18 species of duikers in Africa is an indication of the importance and success

of duikers as dominant forest antelopes while the allopatry they exhibit could be a measure

of the fragmentation of the African forests (Kingdon, 1982 and 1997). Most duikers prefer

forest habitats, but some are adapted to the open, swampy or montane environments

(Kingdon, 1982 and 1997). The grey duiker is the only duiker adapted to savannah and

woodlands habitats. Majority of the duikers are widespread and common in occurrence,

few are vulnerable and threatened like the Ruwenzori duiker (C. rubidus), Peter’s duiker

(C. callipygus), Abbots’ duiker (C. spardix) and zebra duiker (C. zebra) and others like

Aders’ duiker, black duiker (C. niger) and Jentink’s duiker are endangered.



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The future conservation and management of duikers in African forests requires adequate

baseline information on their population status, distribution and the human impact on their

survival. This is important not only in terms of biodiversity conservation, but also in the

context that duikers in each forest provide bush meat that plays an important role in the

socio-economic and cultural life of the people surrounding the forests. Therefore,

extensive survey of forest duikers and their habitats is recommended to provide more

information on their taxonomic and population status that will be used to draw guidelines

for their conservation (IUCN/SSC, 1988).

The current destruction, degradation and fragmentation of forests in Africa through

excisions for settlement, clearing for agriculture and harvesting of forest products for

commercial and domestic uses are greatly threatening the survival of most forest duiker

species (IUCN/SSC, 1988). Another threat to duikers is that many are killed throughout

Africa every year for meat, skins and horns, but there are no effective management policies

to ensure their sustainable utilisation (IUCN/SSC, 1988).

In Arabuko-Sokoke Forest Reserve, Kenya, there are four duiker species; Ader’s duiker

(Cephalophus adersi), blue duiker (C. monticola), red duiker C. natalensi and bush duiker

Silvicapra grimmia. Ader’s duiker appears to be getting increasingly rare throughout its

range in the Cynometra forest. The Aders’ duiker is a small sized forest antelope,

weighing 6-12 kg, with a body length of 66-72 cm, height of 30-32 cm, tail length of 9-12

cm, and horns of 3-6 cm. There is a white band across the buttocks and white freckling on

the legs. The coat is washed out tony red becoming somewhat greyer on the neck, a red

crest on the head and a white and black spot just above the hooves. It can be distinguished

from the other red duikers by its white and black dappled lower midriff to and across its

upper hind-quarters. The fur is soft and silky (Kingdon, 1982; 1997). Ader’s duiker is

diurnal with acute hearing (Acher, 1994).

In Kenya, Aders’ duiker occurs only in Arabuko-Sokoke Forest and its population size is

not well established (Kanga in press). The IUCN/SSC Antelope Specialists Group

classifies it as “Endangered” (East, 1995; Kingdon, 1997). Arabuko-Sokoke Forest

experiences considerable illegal forest exploitation by the community surrounding it



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through extraction of both woody and non-woody products. The present trapping of

animals and habitat distractions through tree logging are major factors identified by

different authors as endangering duikers in the forest (Mogaka, 1991; Davies, 1993; Kanga

in press).

Therefore, this study was designed to generate more information that will be useful in the

conservation and management of duikers in Arabuko-Sokoke Forest with special emphasis

on Aders’ duiker. Population size, density of duikers and human activities in the forest

form the focus of this study. The main objective of this study is to initiate a population

recovery programme for Aders’ duiker in Arabuko-Sokoke Forest, while specific

objectives were: .

Objectives: (I) Establish the population size and density of Ader’s duiker and other duiker

species.

(II) Identify a suitable In-situ breeding site for Ader’s duiker within Arabuko-

Sokoke Forest.

(III) Identify and quantify human activities that may be adversely influence duiker

population in the forest.



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2.0 STUDY AREA

Location: The Arabuko-Sokoke Forest Reserve is found in Kilifi and Malindi District,

Coast Province of Kenya, (Fig. 1). It is one of the last major remnants of lowland forests

on the East African coast (Britton and Zimmerman, 1979; NMK-KIFCON, 1992) and it

covers an area of approximately 416.8 km2, 63 km2 of which comprises a gazetted nature

reserve (Awimbo and Wairungu, 1990; NMK-KIFCON, 1992). The forest lies between

latitudes and longitudes of 3o11’50”S, 39o47’56”E and 3o29’51”S, 40o0’6”E (NMK-

KIFCON, 1992). This is the largest of Kenya's coastal forests and there is a substantial

botanical and zoological evidence, which indicate that it was part of a much more

extensive coastal forest system. Its presently isolated biogeographical nature and the

resultant species endemism give this particular forest its status as an area of considerable

conservation interest (KIFCON, 1995).

Climate: Mean annual rainfall in and around the forest ranges from 900 mm in the south-

western corner to 1000 mm at Gede in the north-east. The dry season lasts from December

to March with the main rains occurring between April and June and smaller amount of rain

falling between July and November. Temperatures are high, with a daily mean of about

25oC and show little monthly variation. Humidity is high at about 60% for most of the

year, due to the proximity of the Indian Ocean (Kelsey and Langton, 1984; KIFCON,

1995).

Topography: The eastern part of the Arabuko-Sokoke Forest Reserve lies on a flat coastal

plain, at an altitude of about 45m above sea level, comprising of sand and coral rags. The

remainder is a plateau, which begins to rise along a line running roughly southwest-

northwest through the middle of the forest. The plateau, 60 to 135m above sea level, is a

seaward sloping plain with underlying Jurassic sediments and easily identifiable by its

distinct red soil, deep and heavily leached with low phosphate contents and low fertility

(KIFCON, 1995). There are a series of seasonal pools, at the base of the plateau, which

disappear in the dry season. There are no perennial rivers or streams running through the

forest (Fanshawe, 1995).



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Figure 1: Location of Arabuko-Sokoke Forest



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Fauna: The fauna in the forest has been less studied than the flora, with the exception of

birds, but there is ample evidence to show that Arabuko-Sokoke is an extremely valuable

fauna reserve. Ten percent (10%) of the country's bird species and about 30% of its

butterfly species are found within this small forest area. More significantly, in terms of

biodiversity, there is an exceptionally high proportion of endemism or near-endemic

species. Six species/subspecies of butterfly, two species of birds, the Sokoke Scops owl

(Otus ireneae) and Clerke's weaver (Ploceus golandi), and three mammal species; the

Golden-rumped elephant shrew (Rhychocyon chrysopygus), Sokoke bushy-tailed

mongoose (Bdeogale crassicauda omnivora) and the Ader’s duiker (KIFCON 1995) are

known to occur in this forest.

Vegetation: The forest covers four distinct vegetation types (Britton and Zimmerman,

1979; Robertson and Luke, 1993; (Fig. 2). The Cynometra manilkera vegetation covers an

area of about 220 km2 and has a variable structure ranging from thickets to forests but is

mainly dominated by Cynometra and lies on the western side of the reserve and above 60m

contour on extremely infertile dark red loams. Branchystegia woodland vegetation covers

an area of about 70 km2 and is characteristic of "miombo" woodland, and occurs on the

eastern half of the forest covering open woodland dominated by Branchystegia

spriciformis trees up to 18m high. This vegetation occupies deep, loose, light-grey to buff

medium to coarse sand. The lowland mixed forest covers about 50 km2, is of limited extent

but shows the greatest diversity of species and occurs in the eastern half with vegetation

growing to no more than 10-12m. The mangrove forest fringing Mida creek, represent

another important ecosystem of the Arabuko-Sokoke Forest, towards the Indian Ocean. It

has seven species of mangrove each adapted to slightly different levels of salt

concentration. The species include; Avucenia marina, Brugueria gymnorrhiza, Ceriops

tagal, Heritiera littoralis, Lumnitzera racemosa, Rhizophora mucronata, and Sonneratia

alba.



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Figure 2: General Vegetation Types in Arabuko-Sokoke Forest.

Source: ASFMT 2002



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3.0 MATERIALS AND METHODS

Drive counts technique

The drive count technique involves cordoning off a randomly pre-selected site of known

size with nets and to scare all duikers into the nets (Kosher and Hart, 1988; Bowland,

1990). By carrying out drive counts on a number of sites, an estimate of duiker population

size and their distribution in the survey area can be obtained. The population size is

estimated as number of duikers encountered multiplied by area surveyed divided by total

area sampled.

The drive count technique assumes that a duiker is not counted twice, all duikers occurring

in the census area are counted and positively identified (Koster and Hart, 1988; Bowland

and Perrin, 1994; Williams et al., 1996). This method is labor intensive, time consuming,

tiring, expensive and requires experienced people who can positively identify duikers.

Other requirements of this technique include familiarity with the census area and good co-

ordination during the drive. However, if this technique is used appropriately, it gives better

results of duiker surveys compared with the other duiker census methods (Koster and Hart,

1988).

A topographic map of Arabuko-Sokoke Forest, scale 1:50000 was used to stratify the forest

into three survey zones, corresponding to the three existing vegetation types. These survey

zones were divided into 4.0 km2 grid cells. In these grid cells, random sampling points

were established using a table of random numbers and later located in the field using a

Global Positioning System (GPS). At every sampling point a rectangular plot of 200m ×

200m (4 ha.) was established. Nets were put up covering the entire U-shape of the plot

(Fig. 3). The nets were 1m high and had an average mesh size of about 12 - 14 mm. Plate

1 shows the drive team fixing the nets while Plate 2 show a net that has been fixed in

position. A team of 14 local people assisted in putting the nets along net-paths on the actual

census day and ‘beat’ the bush making noise as they moved towards the inside of the drive

enclosure. Observers were positioned along the net-path watching, counting and identifying

any duikers flushing past the nets.



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Figure 3: Shape of the drive area showing how nets were set in before a drive took place.



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Plate 1: Members of the drive team unfolding and fixing the nets.

Plate 2: A Net fixed in position ready for the drive.



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Identification of an In-situ breeding site

Availability of natural foods, security from predators and human and terrain were the key

factors considered in identification of an in-situ breeding site. Two sites about 1.5x1.5 km2

(225ha) each in the Cynometra vegetation, one in Komani (Enclosed by GPS lines: 37M

0603000, UTM 9638700 and 37M 0601000, UTM 9640500) and the other in Jilore

(Enclosed by GPS lines: 37M 0602800, UTM 9643000 and 37M 0604700, UTM 9644820)

were pre-selected for in-situ captive breeding on the basis that the Ader’s duiker has been

more frequently sighted there, they have relatively flat terrain and are secure from human

influence. The other consideration was food plants abundance and distribution in the two

sites and this served as the basis for determining the more suitable site.

Sample plots were systematically placed in each of the sites to quantitatively assess duiker

food plants with an aim of determining duiker browse availability. At each sampling point,

concentric sample plots 20mx20m, 4mx4m and 1mx1m on which trees (≥10cm diametre at

breast height, dbh), saplings (<10cm dbh and >1m height) and seedlings (≤1m height) were

enumerated respectively.

Kanga (in press) compiled a checklist of duiker food plants for Arabuko-Sokoke Forest.

The checklist was used to determine duiker food plant species during this study. The

densities and frequencies of the duiker food plants were determined and statistical

comparisons made for the two sites.



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4.0 RESULTS AND DISCUSSION

Mini-antelopes Population Size and Density Estimates.

The population size and density of mini-antelopes in the Cynometra vegetation type was

estimated and presented in table 1 below. The Suni has the highest population compared to

the three duiker species in this vegetation. Plates 3 shows a pair of Sunis (male and female)

caught in the nets. Only 2 individuals of Aders’ duiker were encountered, but outside the

sampling plots. The Aders’ duiker may be in such low densities that it is difficult to

encounter at low sampling intensity. However, we cannot overrule that among the

unidentified mini-antelopes there was an Aders’ duiker, as it is very elusive.

Table 1: Mini-antelopes Population Size and Density in Arabuko-Sokoke (Cynometra

Vegetation 220 km2).

Species Number counted in

sampling plots

Population size estimate

Density estimate

Seen outside sampling plots

Blue duiker 13 1300 5.9 0

Red duiker 9 900 4.1 3

Aders’ duiker - - - 2

Suni 44 4400 20.0 1

Unidentified 5 500 2.3 0

In comparison to an earlier study (Kanga, in press) there is a general decline in population

sizes of the duikers in this vegetation type. The blue and Red duikers population is

estimated to have declined by 51% and 26% respectively. Similarly, it is suspected that the

Aders’ duiker population experienced a decline during the same period due to human

disturbance.

The local community that live around the forest trap animals in the forest for bush meat,

which they consume at their homes or sell to earn some income. Mogaka (1991) estimated

that a total of 576,450 small mammals are trapped from the forest annually. Different

forms of traps targeting different species of small mammals are used. The indiscriminate

trapping of small mammals for bush meat has considerable impact on their population



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sizes and densities in the forest because all sizes of mammals, mature and young alike are

caught. This means that the number of mature breeding individuals continue reducing

while the young do not reach maturity.

Plate 3: A pair of Sunis (male and female) caught in the nets, identified and ready to

be released.

Disturbance in the forest

The main disturbances in the forest are caused by human and elephants. Human

disturbance is mainly in form of animal trapping and tree cutting (Table 2) while elephants

break trees and open up trails in the forest. Plates 4-10 show the various kinds of human

disturbance evidence observed in the forest. The same kind of disturbances were

documented in an earlier study (Kanga, in press; FitziGibbon et al, 1996; Gordon &

dephew, 1995), however, there is a marked increase in frequencies of animal trapping and

tree cutting from this vegetation type since the last study was conducted in 1998.



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Table 2: Frequency of occurrence of the various kinds of disturbances.

Kind of Disturbance Frequency % Relative frequency

Traps 10 28.6

Tree cutting 24 68.6

Fibre harvesting 4 11.4

Human trails 10 28.6

Elephant presence (dung/trails) 9 25.7

Elephant tree breakage 11 31.4

Two tree species Brachylaena huillensis and Oldfieldia somalensis are the main species

felled from the Cynometra vegetation for their carving wood value. Tree cutting and

animal trapping are usually done concurrently by the local people, such that they set

animal traps and move to a different location in the forest where they fell trees. Sometimes

wood carving, especially for O. somalensis is done in the forest to reduce the bulk of wood

to be carried out of the forest but at times especially for B. huillensis logs are carried out of

the forest to the markets. Pole size trees are also harvested from the forest and used mainly

as building material.

Elephants open up trails in the forest thus increasing accessibility to many parts of the

forest. Some animal trappers set so many traps that they even lose track of some, which

may sometimes catch animals that eventually, die and rot on the trap, as evidenced by plate

4. In addition to reducing the number of individual duikers in the forest through trapping,

the increased presence of human beings in the forest interferes with the duikers natural

behaviour such as feeding and breeding, which in turn may affect their population sizes

and densities. The effect of human presence in the forest is magnified by the increased

accessibility as a result of trails opened up by elephants.



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Plate 4: Remains of unidentified mini-antelope that was caught and rotted on the

trap.



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Plate 5: A snare used to catch small mammals especially the elephant shrews in

Arabuko-Sokoke Forest.

Plate 6: A trap used to catch small mammals in Arabuko-Sokoke Forest



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Plate 7: A stack of illegally cut Brachylaena huillensis logs inside the forest awaiting

collection.

Plate 8: A stump of illegally cut Brachylaena huillensis observed inside the forest.



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Plate 9: Remains of Oldfieldia somalensis felled and carved on site.

Plate 10: Some carving tools and unfinished sculptures of Oldfieldia somalensis

retrieved from one of the carving sites.



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Duiker Food Plants

Table 3 shows the density and relative frequency of known duiker food plants in the two

blocks, Komani and Jilore that have been proposed for captive breeding of the Aders’

duiker. There are more food plant species in Komani than Jilore. However, there is no

significant difference in food plant densities (t0.05, (2) 21 = 0.74) in the two sites. Duiker food

plants distribution is significantly different in the two sites (χ20.05, 1= 6.24), with the Komani

site having a more even distribution of duiker food plants.

Table 3: Density and relative frequency of Duiker food plants in the two sites sampled

Trees Density Rel. Freq.

Species Komani Gilore Komani Gilore Cynometra webberi 4250 5200 100 100 Haplocoelum inoploeum 100 25 Manilkala ssp. 550 450 75 67 Strychnos madagascariensis 50 50 13 11

Saplings Canthium mombazense 4375 50 Combretum illairii 19375 6875 75 44 Croton pseudopulchellus 30000 18750 100 100 Cynometra webberi 54375 6875 75 44 Haplocoelum inoploeum 1250 13 Hugonia castaneifolia (Mkuro) 39375 8125 63 44 Manilkala ssp. 4375 2500 50 22 Salacia madagascariensis 6250 3750 25 22 Uvaria ssp. 625 13

Seedlings Combretum illairii 50000 30000 37 33 Croton pseudopulchellus 230000 80000 50 44 Cynometra webberi 810000 1020000 75 100 Hugonia castaneifolia (Mkuro) 130000 160000 63 56 Manilkala ssp. 30000 33 Pavetta ssp. 20000 25 Salacia madagascariensis 20000 25 Strychnos madagascariensis 20000 13 Uvaria ssp. 30000 10000 13 11



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Although the two sites have similar food plant densities, the Komani site could be more

preferred for a captive breeding facility for Aders’ duiker due to its higher duiker food

plants diversity and a more even distribution of the food plants. A higher diversity of food

plants is important in that the plants will exhibit a higher diversity in phenoloy (flowering,

fruiting, leaf shedding etc) within the site thereby providing the duikers with variety of

food plant parts most of the time. A more even distribution of food plants is advantageous

in that the probability of encountering a food plant within any part of the site would always

be higher.

Other Mammals Recorded in the Forest. Table 4 shows the estimated population size and density of other small mammals

encountered in the Cynometra vegetation during this survey and density for some

mammals estimated in 1994 (Fitzgibbon et al, 1995). There is a general declining trend of

most of the species population. Of key interest is the Golden-rumped elephant shrew (plate

11), an endangered species that also indicates a declining trend in density. The reducing

density may be a result of the increasing animal trapping in the forest (plate 12).

Table 4: Population size and density estimates of other small mammals encountered

during this Survey (Cynometra Vegetation)

Species Number Population

size

Current

Density

Estimate

(No./km2)

1994 Density

Estimates

(No./km2)

Four-toed Elephant shrew 109 10900 49.5 391.2

Pocupine 1 100 0.5

Red-berried ground squirrel 49 4900 22.3

Sykes monkey 2 200 0.9 57.7

Dwarf mongoose 5 500 2.3

Genet cat 1 100 0.5

*Golden-rumped Elephant shrew 39 3900 17.7 58.9

Tree Squirrel 5 500 2.3 11.0

* An endangered species.



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Plate 11: A golden-rumped elephant shrew (endangered) caught in the net identified

and ready to be released

Plate 12: A dead four-toed elephant shrew retrieved from one of the traps during the

drives.



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5.0 Conclusions and Recommendations

Despite the protection efforts illegal human activities such as animal trapping and tree

cutting are still persistence and on the increase in Arabuko-Sokoke Forest. These human

activities have significant impacts on duiker population sizes and densities and therefore

have implications on their conservation and management. It is important that the current

Strategic Forest Management Plan for Arabuko-Sokoke be implemented in conjunction

with the existing National Law and Policy in order to achieve greater success in illegal

activity reduction in the forest. More resources should therefore be availed.

The population size and density of Ader’s duiker in Arabuko-Sokoke is low and the

numbers continue to decline due trapping and other influences on their habitat by human.

A recovery programme for the Ader’s duiker which is endangered is therefore justified,

considering that it is only found in this forest in Kenya. The recovery programme should

focus on introduction of Ader’s duiker individuals into the forest in order to boost the

breeding population and make efforts to reduce trapping by the local people. The efforts to

reduce trapping by the local people, that could be achieved through introduction of

alternative sources of meat and income generating activities are envisaged to help in the

conservation of other small mammals in the forest.

Actions for Conservation and Recovery of Aders’ duiker

The Ader's duiker is fully protected from hunting under the Kenyan Laws (CAP 376). The

new Environmental and Management Act (2000) provides further protection for the Ader's

duiker and other wildlife species. This legislation has been implemented in full and give

authority to Kenyan citizens to sue in cases where they have evidence of environmental

offences, being committed by other citizen.

However, despite the degree of protection accorded to the Kenyan wildlife under National

laws, the same laws have not been effectively enforced such that the Aders’ duiker has

been continually trapped / hunted and its habitat degraded heavily in recent years, to the

extent that the species population has undergone a severe decline. With the current

conservation initiatives and advocacy at the community level, the extent and intensity of

human pressure is expected to decline in Arabuko-Sokoke Forest.



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The following management actions are proposed to enhance continued conservation and

recovery of Aders’ duiker:

Education and awareness

• Continued intensified environmental education among the law enforcers and offenders.

This will boost sufficient law awareness and conservation status of Aders’ duiker. It is

realized that integration of human in conservation is inevitable and I propose to work

with conservation oriented groups (community forest guides and other groups) to

enhance their socio-economic status and enhance their level of understanding the

importance of sustainable use of Arabuko-Sokoke Forest. Figure 4 shows the

administrative boundaries and human population estimates around the forest.

Ø A localized conservation education campaign to advocate for the conservation

of the mini-antelopes in Arabuko-Sokoke Forest will be carried out through

Schools’ program, Barazas’ and workshops.

Ø Lobby and campaign amongst all stakeholders working in the forest to insure

that the Ader's duiker is appropriately listed and included in all relevant

development projects being undertaken around Arabuko-Sokoke Forest.

Ø People's awareness of wildlife and forest conservation issues is gradually

increasing amongst the community around the forest. The general public's

awareness about conservation issues should be much higher and a concerted

effort to educate people about the increasing decline of the natural resource

base and the finite extent of natural resources should be made. Indeed, in this

contest the likely extinction of some species and the decline of the Ader's

duiker population can be used as examples.

Ø Interpretative material for school curricula should be prepared and schools

encouraged to bring their pupils to Arabuko-Sokoke Forest. The education

Center at the KWS Arabuko-Sokoke Forest Station should be further supported.

Funding for school to visit this center (largely transport and interpretative

materials) should be secured.



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Figure 4. Administrative boundaries of locations surrounding Arabuko-Sokoke Forest, with indications of Human population density estimates

Source: ASFMT, 2002



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InSitu Captive breeding

• Ader's duiker will continue to be threatened by hunting and habitat destruction to a

lesser or greater degree in Arabuko-Sokoke Forest for the foreseeable future.

Therefore, there is imperative need to consider setting a captive breeding center on a

small, localized scale in the Aders’ duiker range, to try and build up numbers of these

endangered duiker.

Ø It is proposed that a captive breeding facility be set up in the Cynometra vegetation

(Komani site) in partnership with one or more organisations experienced in captive

breeding of duikers. It is proposed that an initial 4 year funding agreement is

necessary with a further 4 year project completion period required. There is need to

approach the European Association of Zoos and Aquarium.

Lobby for enlargement of the current Nature Reserve area

• Prepare a detailed proposal, lobbying for the enlargement of the existing Nature

Reserve within Arabuko-Sokoke Forest (67 km2), to secure larger parts of the Aders’

duiker range in the forest.

Ø The realization of an effective enlarged protected area will effectively protect

Ader's duiker, while intensified patrols in an area with strict rules on no human

interference policy and stiff penalties for law-breakers will deter illegal

activities.

Strengthen law enforcement

• Organize and support regular coordinated joint patrols comprising of the lead

government departments working in Arabuko-Sokoke Forest. This will foster

cooperation between the various government departments, implementing biodiversity

protection in the forest (these includes; Kenya wildlife Services, Forest Department,

Kenya Forest Research Institute, National Museums of Kenya).

Support in-come generating activities

• Effort should be put on accelerating funding on current community projects like bee-

keeping, butterfly farming, and training more people on use of energy saving cookers,

to reduce fuel wood harvesting from the forest. The expected output will be improved



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socio-economic status of the community (livelihood) and energy conservation through

reduced fuel wood harvesting from the forest.

Research and Monitoring

• The status of Ader's duiker in Arabuko-Sokoke Forest needs to be monitored so that

the performance of management actions can be effectively reviewed. Monitoring is

often forgotten or relegated to a last priority especially when resources are in short

supply. Thus the monitoring programme for Ader's duiker will need to be sufficiently

comprehensive and sustainable in terms of its demand on resources, personnel and

time.

Ø At least every three years, a full survey of the population of Ader's duiker

should be carried out. The methodology of the survey should be such that the

survey can be used directly as a comparison with previous population estimates.

It is recommended that the survey methodology be based on that used in 1998

(Kanga, in press). If resources allow, the population survey should be carried

out more frequently. Smaller studies could be carried out at shorter intervals as

well.

Ø A simple research programme to understand more about the behavioral and

population ecology of the Ader's duiker in Arabuko-Sokoke Forest should be

embarked upon. It is suggested that in the absence of funding for a research

programme, that a post-graduate students of an appropriate biological field be

encouraged to carry out supervised research projects.

Ø A human activity management data base be developed and maintained.

Information on this aspect should be collected on a monthly basis which details

the quantity and frequencies of human activities in various parts of the forest.

This will enable an overall view of the following indicators to be developed, to

be assessed in different management zones of the forest as shown on figure 5

♦ Human activity spread in different parts of the forest.

♦ The level of illegal duiker trapping in various part of the forest.

♦ The generation of an index of the overall mini-antelope population off-

take and intensity of illegal trapping.



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♦ The number of animal traps and incidences of tree cutting, that will

indicate the effectiveness and respect for law enforcement by the wider

community surrounding the forest.

Figure 5. Proposed Zonation of Arabuko-Sokoke Forest

Source: ASFMT, 2002



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6.0 LITERATURE CITED.

Archer, A. L. (1994). A survey of hunting techniques and the results thereof on two

species of duiker and the suni on Zanzibar Island. Zanzibar Forestry Development Project.

Technical paper - 17.

ASFMT, (2002). Arabuko-Sokoke Strategic Forest Management Plan 2002 - 2007

Awimbo, J. A. and Wairungu, S. N. (1990). The ecology and conservation of the

Arabuko-Sokoke Forest. Forest Ecology Division. KEFRI.

Bowland, A. E. and Perrin, M. R. (1994). Density estimate methods for blue duiker

Philantomber monticola. J. of Afr. Zool. 108.

Bowland, A.E. (1990). The ecology and conservation of the blue duiker, Philantomba

monticola and red duiker Cephalophus natalenisis. PhD. Thesis, University of Natal,

Pietermaritzburg, SouthAfrica.

Briton, P. l. and Zimmerman, D. A. (1979). The avifauna of Arabuko-Sokoke Forest,

Kenya. J. East afri. Nat. Hist. Soc. 169: 1-15

Davies, G. (1993). Arabuko-Sokoke Forest Reserve: Biodiversity overview. Unpubl.

Report KIFCON

East, R. (1995). 1996 IUCN Red list. Gnusletter Vol. 14, no. 2 and 3.

Fanshawe, J. H., (1995). Effects of selective logging on bird community of Arabuko-

Sokoke Forest, Kenya. Ph.D. Thesis, Oxford University.

Fitzgibbon, C. D., Mogaka, H., and Fanshawe, J. H. (1995). Subsistence hunting in

Arabuko-Sokoke forest, and its effects on mammal population. Conserv. Biol. 9: 1116-

1126.



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Fitzgibbon, C. D., Mogaka, H., and Fanshawe, J. H. (1996). Subsistence hunting and

mammal conservation in a Kenyan coastal forest: resolving a conflict. In: Tylor V.J. (eds.)

The Exploitation of Mammal populations. Chapman and Hall, London.

Gordon, I. and Dephew, L. (1995). The Kipepeo Project. Swara 18: 15-17.

Hofmann, R.R., (1973). The ruminant stomach. E. Afr. Monog. in Biol., Vol. 2

Kanga, E.M. (in press). Some ecological Aspects of duikers in Arabuko-Sooke Forest.

MSC Thesis, University of Nairobi.

Kelsey, M. G. and Langton, T. E. S. (1984). The conservation of the Arabuko-Sokoke

Forest, Kenya. International Council for Bird Preservation.

KIFCON (1995). Forest inventory report no. 2. Arabuko-Sokoke. Karura Forest Station,

Nairobi

Kingdon, J. (1997). The Kingdon field guide to African Mammals. Academic press.

London.

Kingdon, J. (1982). East African mammals. An Atlas of Evolution in Africa Vol. 3, Part C

(Bovids), Academic Press, London.

Koster, S. H., and Hart, J. A. (1988). Methods of estimating ungulates population in

tropical forests. Afri. J. of Ecol. 26: 117-126.

Mogaka, H. R. (1991). Local utilization of Arabuko-Sokoke Forest reserve. Unpublished

KIFCON Report, Nairobi: Karura Forest Station.

Newing, H.S. (1994). Behavoiural Ecology of Duikers (Cephalophus spp.) in Forest and

Secondary Growth, Tai, Cote d’Ivore. Ph.D. thesis, University of Stirling.



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Robertson, S. A. and Luke, W. R. Q. (1993). Kenya coastal forests. The report of the

NMK/WWF Coast Forest Survey. WWF Project 3256: Kenya, coast forest status,

conservation and management.

Williams, A., Mwinyi, A. A, and Ali, S. J., (1996). A population survey of the mini-

antelopes; Ader’s duiker, Blue duiker and suni of Unguja Zanzibar. Unpubl. report for

Commission for Natural Resources, Zanzibar.



Project report 2002 - Aders' duiker in ASF.pdf

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