INVERTEBRATE MONITORING FOR ASSESSING ECOSYSTEM …

ES LINK SERVICES PTY LTD ABN 76 088 414 037

1 Queensberry Place, North Melbourne VIC 3051

T (03) 9274 9405 F (03) 9328 2744 E [email protected] W www.eslinkservices.com.au

Linking sustainable economic returns with environmental and social outcomes

INVERTEBRATE MONITORING FOR ASSESSING ECOSYSTEM HEALTH AND SUSTAINABILITY IN THE CORANGAMITE CATCHMENT

Prepared for:

Corangamite Catchment Management Authority 64 Dennis Street COLAC VIC 3250

31 May 2007

Invertebrate Monitoring in the Corangamite Catchment

INVERTEBRATE MONITORING FOR ASSESSING ECOSYSTEM HEALTH AND SUSTAINABILITY IN THE CORANGAMITE CATCHMENT

Prepared for:

Corangamite Catchment Management Authority 64 Dennis Street COLAC VIC 3250

Prepared by:

Dr. Andrew Weeks CESAR Consultants

Dr. Richard Woods & Nicholas Lewis ES Link Services Pty Ltd

31 May 2007 Page i


31 May 2007 Page ii

Version control

Date Version Description Author Reviewed By

1 May 2007 1.0 Preliminary Draft for review and comment on direction by Corangamite CMA

AW & RW NL

31 May 2007 2.0 Final Report for Corangamite CMA

AW & RW NL

Abbreviations

Abbreviations Description

AFSCT Agroforesty for Salinity Control Trial

AUSRIVAS Australian River Assessment Scheme

CESAR Centre for Environmental Stress and Adaptation Research

CMA Catchment Management Authority

EPA Environmental Protection Authority

IOBC International Organisation for Biological Control

ISC Index of Stream Condition

NRHP National River Health Program

NRM Natural Resource Management

RCS Regional Catchment Strategy

RBP Rapid Bioassessment Protocols

SIGNAL Stream Invertebrate Grade Number – Average Level


31 May 2007 Page iii

Table of Contents

1 Introduction ..................................................................................................................................................................1 1.1 Project context....................................................................................................................................................1 1.2 Report structure..................................................................................................................................................1

2 Invertebrate monitoring in terrestrial environments ................................................................................................2 2.1 Introduction........................................................................................................................................................2 2.2 Invertebrate monitoring as an indicator of environmental change in terrestrial environments...........................3 2.3 Invertebrates as indicators of sustainability in agriculture .................................................................................4

2.3.1 Introduction ...........................................................................................................................................4 2.3.2 Landscape management and effects on invertebrates including pests ...................................................4 2.3.3 Pesticide residues and effects on invertebrate fauna .............................................................................8 2.3.4 Summary ................................................................................................................................................8

2.4 Innovations in terrestrial invertebrate monitoring ..............................................................................................9 2.5 Current terrestrial monitoring programs in Australia .........................................................................................9 2.6 Review of previous invertebrate monitoring programs in the Corangamite region..........................................10

2.6.1 Introduction .........................................................................................................................................10 2.6.2 Neville (2003). Assessing the biodiversity value of invertebrates within shelterbelts ..........................10 2.6.3 Lewis (2003). Can invertebrates be used as indicators of dryland salinity? The identification of

candidate assemblages in south-western Victoria ...............................................................................12 2.6.4 Neville (2003). Assessing succession and biodiversity of invertebrates within revegetation areas:

Apollo Bay revegetation project ..........................................................................................................14 2.6.5 Tsitsilas et al. (2006). Shelterbelts in agricultural landscapes suppress invertebrate pests ................16 2.6.6 Gower et al. (2007). Effectiveness of spring spraying targeting diapause egg production for

controlling red legged earth mites and other pests in pasture .............................................................19 2.6.7 Tsitsilas et al. (2007). Grass cover characteristics and their effects on beneficial organisms and pests

in adjacent pasture. .............................................................................................................................22 2.6.8 Summary ..............................................................................................................................................23

2.7 Knowledge gaps in invertebrate monitoring in terrestrial environments..........................................................24 2.8 Conclusion .......................................................................................................................................................24

3 Invertebrate monitoring in aquatic freshwater environments................................................................................26 3.1 Introduction......................................................................................................................................................26 3.2 Current monitoring programs in Australia .......................................................................................................26 3.3 Recent innovations in invertebrate monitoring in aquatic environments..........................................................27 3.4 Overview of previous monitoring programs in the Corangamite region ..........................................................29 3.5 Knowledge gaps in aquatic monitoring programs using invertebrates .............................................................32 3.6 Conclusion .......................................................................................................................................................32

4 Towards using indicator invertebrate species in the Corangamite Catchment.....................................................34 4.1 Introduction......................................................................................................................................................34 4.2 The Adaptive Management Framework...........................................................................................................34 4.3 Integrating Invertebrate Indicators ...................................................................................................................36

4.3.1 Identification of an invertebrate indicator...........................................................................................36


31 May 2007 Page iv

4.3.2 Integration with the Corangamite Regional Catchment Strategy ........................................................37 4.3.3 Incorporating invertebrate indicators into the Monitoring and Evaluation Framework .....................39

5 Conclusion...................................................................................................................................................................41

6 References ...................................................................................................................................................................43


31 May 2007 Page 1

1 INTRODUCTION

1.1 Project context Biological indicators of catchment health and sustainability add significant value to non-biotic indicators, enabling accurate reporting of catchment health. Organisms live in the ecosystem and are therefore best placed to indicate the health and sustainability of their environment. The benefits of biological indicators include the ability to detect biologically relevant impacts (both positive and negative) of threatening processes or interventions. Intuitively, the best biological indicators will be those that are directly impacted by changes to the environment, are in large numbers and display low movement rates. Invertebrate organisms generally fulfil these requirements and are increasingly being accepted as tools that can be used to indicate the health of an ecosystem.

In 2002 the Corangamite Catchment Management Authority (CMA) invested in a preliminary study investigating the utility of invertebrates as indicators of catchment health in terrestrial environments. This seed funding provided a sound base for additional research and investment by the Centre for Environmental Stress and Adaptation Research (CESAR) at The University of Melbourne. A range of invertebrate surveys and experiments have now been completed in the Corangamite region across the broad natural resource themes of sustainable agriculture, soil health, waterways, biodiversity and native vegetation.

This report aims to synthesize the current knowledge on invertebrate biomonitoring in the Corangamite region and place the results in the global context of using invertebrates as indicators of ecosystem health and sustainability. The report will inform the identification of potential invertebrate indicators in terrestrial and/or aquatic environments. Key knowledge gaps are identified and targets for future work, including the development of an invertebrate monitoring program, are discussed.

1.2 Report structure Chapters 2-4 provide the main part of this ‘State of Knowledge’ report.

Chapters 2 and 3 provide a review of invertebrate indicators, including a review of projects conducted in the Corangamite Catchment. Chapter 3 deals with terrestrial biomonitoring and provides a review of this emerging field including all identified research projects conducted in the Corangamite Catchment. Chapter 4 deals with aquatic biomonitoring and provides a brief overview of this established field. Both chapters also provide an overview of knowledge gaps, as well as recent innovative approaches to invertebrate biomonitoring.

Chapter 4 addresses the potential for developing indicator species for monitoring the health and sustainability of terrestrial and aquatic environments in the Corangamite Catchment.


31 May 2007 Page 2

2 INVERTEBRATE MONITORING IN TERRESTRIAL ENVIRONMENTS

2.1 Introduction Changes in land use, habitat fragmentation, nutrient enrichment and environmental stress often affect species composition and diversity in ecosystems. These changes in land use, often induced by agriculture, are among the most immediate drivers of species diversity (Perner and Malt 2003). Therefore, it makes sense that we can use biological monitoring to determine the health, both at a local and regional scale, of ecosystems. The advantage of including biomonitoring in evaluation systems over the sole use of physical and/or chemical data are that living organisms occupy their habitat continuously and experience the stressors, changes and modifications taking place therein. Their response integrates the cumulative effects of environmental change over time, and they may be sensitive to several different stressors simultaneously. Relying solely on physical and/or chemical properties of an environment can therefore give a biased view of how these properties may actually affect organisms that live within an environment and our interpretation of the health of that ecosystem. Therefore, biological monitoring provides a means to assess the biological significance of changes within an environment.

Biological monitoring is not a new concept and has been used broadly in many different fields for indicating habitat alteration, destruction, contamination and rehabilitation, vegetation succession, climate change and species diversity (McGeoch 1998). Plants and plant communities, as well as vertebrates (such as birds) and microorganisms, have been frequently used as bioindicators for environmental monitoring (see McGeoch 1998). But there are major drawbacks for using these taxa as bioindicators. Plants, because of their slow population turnover times and slower dispersal are relatively less responsive indicators of change. Vertebrates, with their much higher migration potential (and in the case of birds, their migratory patterns), slow generation time and generally low numbers, are also limited as indicators of environmental change. Similarly, microorganisms respond very rapidly to changing environmental conditions, often fluctuating wildly, and therefore are less stable indicators of long-term trends.

In terrestrial landscapes, invertebrates constitute a substantial proportion of species richness and biomass (> 65 per cent; Jeanneret, Schupbach et al. 2003), and play a significant role in ecosystem functioning. Invertebrate community composition also offers insight into ecosystem function and interaction due to the wide range of functional groups represented (Pik, Dangerfield et al. 2002). Invertebrates are abundant medium-sized organisms that, as a generality, have growth rates and population turnover times lying midway between those of microorganisms and higher plants and animals. They also have effective active and passive dispersal mechanisms that allow wide dissemination and rapid recolonization of disturbed habitats. All these attributes make invertebrates highly suitable and the most likely choice as bioindicators of environmental change.

While the logical choice as indicators of catchment health, there are a number of hurdles that must be overcome before invertebrates can be routinely used in monitoring programs. Numerous studies indicate the potential of some groups of invertebrates as bioindicators (and these are highlighted in Appendix 2), but while groups can be universally applied, often local knowledge of the makeup of these invertebrate groups is needed.


31 May 2007 Page 3

This chapter outlines some of the issues of terrestrial invertebrate biomonitoring and provides a review of past and current projects that have been conducted in the Corangamite Catchment.

2.2 Invertebrate monitoring as an indicator of environmental change in terrestrial environments

The utility of invertebrates for assessing environmental conditions in aquatic ecosystems has long been recognized and this has spawned a number of biological monitoring tools that use aquatic macroinvertebrates. These monitoring methods recognize that different invertebrate taxa tolerate organic pollution to a lesser or greater extent and that their differing responses can be used to indicate water quality (see chapter 3). In terrestrial environments, the use of invertebrates in monitoring and assessment is much less developed for which there are a number of reasons. Foremost is the social complexity associated with terrestrial environments at the landscape level where agriculture and its practice impact heavily on biodiversity. In Australia, these social complexities have resulted in a lack of specific regulations for terrestrial environments and therefore the lesser need to assess compliance. Others (Andersen, Fisher et al. 2004) also suggest that this reflects the lower prominence of invertebrates within terrestrial ecology more broadly when compared to limnology, especially in Australia.

In its rawest form, the most direct way of monitoring invertebrate biodiversity to assess changes in terrestrial environments is to sample entire invertebrate assemblages. This would involve surveying and identifying large numbers of taxa, and although it has its uses when initially trying to develop bioindicators for particular systems, the efficiency and technical expertise required for this approach is impractical. Generally, researchers and land managers will focus on particular groups of invertebrates that reflect broader patterns of invertebrate biological integrity.

In terrestrial environments, most attention has been paid to developing indicator invertebrate taxa for habitat management, degradation, restoration and improvement. Invertebrate taxa that have been suggested in this regard include ants, beetles, spiders, mites, earthworms, moths and even bees (see Appendix 2). However, it is not unreasonable to expect that just about any invertebrate taxa could be used in this regard as we are generally talking about successional changes in total biodiversity (in the case of restoration, starting from a very low level and increasing). In the northern hemisphere, beetles are regarded widely as bioindicators of habitat change, while in Australia there has been a concerted effort promoting ants as universal bioindicators in terrestrial environments with the development of ant functional groups (Andersen, Fisher et al. 2004).

In the Corangamite Catchment, greater than 70 per cent of its area is defined as agricultural land, the majority of which is pastoral. A key component of any program promoting health within the Corangamite Catchment will include sustainable agriculture. Invertebrate monitoring can have a huge influence on determining sustainability and provide land managers with options on best practice methods for maintaining biodiversity, reducing pest pressure and increasing farm profitability.


31 May 2007 Page 4

2.3 Invertebrates as indicators of sustainability in agriculture

2.3.1 Introduction

“Sustainable agriculture is the management and utilization of the agricultural ecosystem in a way that maintains its biological diversity, productivity, regeneration capacity, vitality and ability to function, so that it can fulfill – today and in future – significant ecological, economic, and social functions at the local, national, and global level, and that does not harm other ecosystems”

(Lewandowski, Hardtlein et al. 1999)

The intensification of agriculture in Australia and throughout the world in the last century has led to an alarming level of ecological degradation. However, many developed countries, including Australia, are now increasing their efforts to restore agricultural landscapes and enhance biodiversity by implementing agri-environmental programs, such as introducing semi-natural habitats and field margins (shelterbelts) into farmlands. Similarly, the reliance on pesticides to control pest invertebrates and weeds is becoming an untenable option with the increase in resistance in many pest organisms, and more sustainable options are now being sought in different agricultural industries.

Unfortunately, there is still some resistance by farmers and land managers to implement strategies that are more sustainable because the benefits are not always immediately apparent; why dedicate a part of productive farmland that has immediate economic benefits to a revegetation program? To convince farmers and land managers to take more sustainable options in agriculture there is a need to show direct benefits for these options. This is of critical importance for the Corangamite CMA.

Increasing invertebrate biodiversity on farm land can actually provide direct benefits and promote sustainable agriculture through reductions in invertebrate pest pressure, higher nutrient turnover in soils, increases in plant pollination and greater efficiency of ecosystem services. By directly showing these benefits to farmers and land managers, resistance to sustainable farming options are likely to be greatly reduced. This needs to be a focus of invertebrate monitoring programs in the Corangamite Catchment so that the Regional Catchment Strategy (RCS) targets related to Sustainable Agriculture can be achieved. Below, two areas of immediate relevance to sustainable agriculture within the Corangamite Catchment are discussed with reference to the benefits of promoting terrestrial invertebrates for pest control.

2.3.2 Landscape management and effects on invertebrates including pests

The relatively homogenous environments created by agriculture have resulted in a loss of biodiversity, including invertebrate diversity. Unfortunately, there is also an increasing amount of evidence that suggests a link between these ‘monocultures’ and invertebrate pest problems in agriculture. In Australia, the adoption of within-field monocultures is believed to be a major factor underlying the nature and severity of pest problems in crop production systems (Gurr, Wratten et al. 2004). Similarly, the clearing of land for pasture has reduced biological complexity and provided a ‘sterile’ haven for pests.

In the Corangamite Catchment there are a number of invertebrate pests that impact significantly on agriculture (see figure 1). In particular, the red legged earth mite, Halotydeus destructor, the blue oat


31 May 2007 Page 5

mite, Penthaleus spp., and the lucerne flea, Sminthurus viridis, are significant pests of pasture environments where they reduce available feed for livestock and are the major establishment pests of winter grain crops. Control methods for these pests currently rely solely on chemical applications, but this is not a sustainable option and may exacerbate the problem (see Gower et al. (2007) – Section 2.6.6, below).

The loss in biodiversity in agro-ecosystems can be countered to some extent by increasing vegetation diversity through the provision of non-crop habitats such as those provided by shelterbelts, within field refuges, hedgerows, remnant vegetation and herbaceous strips within crops. This habitat manipulation, widely known as ecological engineering, is an emerging science in agricultural landscapes for the endemic control of invertebrate pests (see Gurr, Wratten et al. 2004). Numbers of natural enemies of pests (see figure 2 for examples) can be increased in these habitats by providing overwintering sites, alternative prey and hosts, food sources such as pollen and nectar for parasitoids and predators, which can lead to more effective biological control of pests. For instance, within field refuges in corn crops are known to increase carabid beetle densities (Carmona and Landis 1999), important predators of insect pests of corn. Similarly, complex habitat boundaries (consisting of deciduous forest vegetation) were shown to increase generalist parasitoids of armyworm, one of the major pests of corn crops (Marino and Landis 1996).

It is likely that increasing habitat heterogeneity adjacent to crops may provide a more sustainable choice of pest control. Understanding the characteristics that promote the key invertebrate predators needs to be considered when designing these habitats. Increases in invertebrate biodiversity in these habitats will also provide improved ecosystem function in agricultural landscapes, and add to a more resilient system.


Figu

re 1

. M

ajor

pes

ts o

f agr

icul

ture

with

in th

e C

oran

gam

ite C

atch

men

t; (a

) the

redl

egge

d ea

rth m

ite, H

alot

ydeu

s de

stru

ctor

, (b)

the

blue

oat

mite

, Pen

thal

eus

maj

or, (

c) th

e lu

cern

e fle

a, S

min

thur

us v

iridi

s, (d

) the

cer

eal

aphi

d, R

hopa

lisip

hum

pad

i, (e

) the

mite

Bal

aust

ium

spp

., (f)

the

mite

Bry

obia

spp

., (g

) the

slu

g Le

hman

nia

nyct

elia

, (h)

the

yello

w-h

eade

d pa

stur

e co

ckch

afer

, Ser

ices

this

gem

inat

a, (g

) the

true

w

irew

orm

(Fam

ily E

late

ridae

).

31 May 2007 Page 6


31 May 2007 Page 7

Figu

re 2

. Ty

pica

l pre

dato

ry in

verte

brat

es fo

und

with

in s

helte

rbel

ts o

r rem

nant

veg

etat

ion

that

can

pro

vide

end

emic

co

ntro

l of p

ests

in a

gric

ultu

ral s

yste

ms;

(a) b

row

n la

cew

ing,

(b) h

over

fly, (

c) ju

mpi

ng s

pide

r, (d

) lad

ybug

, H

arm

onia

con

form

is, (

e) C

arab

id b

eetle

, Not

onom

ous

grav

is, (

f) gr

een

lined

gro

und

beet

le, C

atad

rom

us

laco

rdai

rei

(g) g

arde

n or

b sp

ider

, (h)

com

mon

blu

etai

l dam

selfl

y, Is

chnu

ra h

eter

ostic

ta, (

i) pr

ayin

g m

antid

.


31 May 2007 Page 8

2.3.3 Pesticide residues and effects on invertebrate fauna

The management of pests and diseases remains a key issue for agricultural profitability and environmental health. Chemicals still remain the main method of pest and disease control in many agricultural industries but they have negative effects on natural enemies (predators and parasitoids) that exert control of pests. Most chemicals applied in agricultural systems in Australia are considered ‘hard’ to all invertebrate fauna in that they do not target invertebrate pests specifically. These ‘hard’ chemicals kill invertebrate fauna, including beneficial predators, and thereby can actually increase pest problems (see project by Gower et al. (2007) below for example). This results in a lack of sustainability in the agro-ecosystem by creating a dependence on chemicals for the future control of invertebrate pests. It is also not parsimonious with increasing habitat complexity for endemic biological control of pests mentioned above and may actually negate any influences provided by habitat manipulation.

A recent study by Thomson and Hoffmann (2006) highlights the importance of reducing pesticide applications within an agro-ecosystem to increase biodiversity. These authors used IOBC (International Organization for Biological Control; http://www.iobc-wprs.org/) pesticide toxicity ratings for beneficial organisms to formulate a ‘farm score’ (low number good, high number bad) for a number of vineyards in the Yarra Valley, Victoria over a single season. Invertebrates were then collected and sorted to family or lower levels and those with ecological functions important to vineyards (not including pests) were correlated to the ‘farm pesticide scores’. Even though their data was statistically limited (only 19 vineyard sites were assessed), the authors found highly significant negative correlations between farm pesticide scores and ecologically important invertebrate groups. As farm pesticide score increased, functional invertebrate biodiversity decreased. This is the first study that has directly shown the impact of pesticide spraying regime in an agricultural context on important beneficial invertebrate groups.

The results of Thomson and Hoffmann (2006) highlight the importance of reducing chemical input into agricultural systems if resilience and sustainability are to be achieved. Softer pesticides (chemicals that target a pest specifically while being non-toxic to beneficial invertebrates), used in conjunction with more judicious timing of application and increases in habitat heterogeneity to promote biodiversity, could provide a more sustainable means of pest control. If the method of Thomson and Hoffmann (2006) is validated in other agricultural systems (i.e. livestock and cropping environments), land managers will be able to provide chemical input/biodiversity impact ratings to their farms. This may become important to the Corangamite CMA as government and industry regulatory bodies change environmental policies for sustainable agriculture in the future.

2.3.4 Summary

Recent research has highlighted how increasing and/or maintaining invertebrate biodiversity, and in particularly predatory invertebrates, can help reduce pest pressure within agricultural ecosystems. The relatively homogenous environments created by agriculture and the intense use of pesticides have reduced biodiversity within agroecosystems to a very poor level. By increasing habitat heterogeneity surrounding crops, pastures and agricultural fields, increases in invertebrate biodiversity are possible and can result in the endemic control of invertebrate pests. However, unless chemical applications for the control of invertebrate pests are reduced, then the increase in biodiversity will be temporary and endemic control of invertebrate pests will not be possible.

http://www.iobc-wprs.org/


31 May 2007 Page 9

2.4 Innovations in terrestrial invertebrate monitoring While advances have been made developing certain invertebrate groups as indicators of particular environmental changes, largely there have been few major innovations in terrestrial biomonitoring recently. There are still several burgeoning issues that have held back this field such as: (1) lack of taxonomic expertise and speed at which samples can be processed; (2) lack of studies directly correlating changes in the environment with particular invertebrate taxa; and (3) the apparent localised or endemic nature of invertebrate diversity.

The one area that has progressed is the link between biodiversity and sustainable agriculture. The study of Thomson and Hoffmann (2006), directly linking pesticide use with impacts on beneficial invertebrate fauna is a crucial step in developing sustainable agricultural practices. Several studies performed in the Corangamite Catchment outlined below, also provide innovative approaches to linking terrestrial invertebrate monitoring with sustainable agriculture and the control of invertebrate pests.

2.5 Current terrestrial monitoring programs in Australia Despite the benefits already mentioned for using invertebrates as bioindicators, terrestrial invertebrate monitoring programs are largely in their infancy both within Australia and abroad. This is in contrast to aquatic invertebrate monitoring programs which are well established throughout the world (see Chapter 3). The reason for this difference is likely to be the relative importance of aquatic versus terrestrial environments for human health. Humans need clean, healthy water to survive. Therefore governments have fostered the aquatic invertebrate monitoring field through legislation, new regulatory laws and mandates (Bonada, Prat et al. 2006). This has not been the case in terrestrial environments, although this does appear to be changing.

In Europe, the most widely used invertebrate terrestrial indicators are beetles from the family Carabidae. A worldwide program was launched in 2000 (GLOBENET) to use this single family as indicators of habitat change/modification (Niemela, Kotze et al. 2000). The program is designed to use carabids to determine large scale patterns of human induced disturbance and separate these from localized processes to help sustainably manage landscapes for biodiversity and human requirements. Unfortunately, within Australia carabid beetles are relatively scarce and there is a general lack of ecological and taxonomic understanding of the Australian fauna (Andersen, Fisher et al. 2004). This has limited their applicability for monitoring programs in Australia.

In Australia there has been a large focus on ants as bioindicators and they are currently used successfully in several monitoring programs. They were initially developed as a monitoring system for assessing restoration success following mining (Majer 1983) and are now well entrenched in the mining industry as part of programs for best practice environmental management (Andersen, Fisher et al. 2004). Ants have also been applied to other land use situations including offsite mining impacts, forest management, conservation assessment and grazing impacts in rangelands (Andersen, Fisher et al. 2004). They have also been shown to reflect changes in other invertebrate groups following disturbance (King, Andersen et al. 1998; Majer 1983), indicating that they are a good surrogate group for reflecting changes in invertebrate diversity and structure. To simplify their use as bioindicators beyond taxonomic experts, ants have been formally structured into a global model of functional groups in relation to environmental stress and disturbance.

http://www.helsinki.fi/science/globenet/


31 May 2007 Page 10

While there use in monitoring habitat disturbance appears to be well developed, ants may not be good indicators of particular stressors that are relevant to agriculture. Several recent studies have found that ants do not respond to two particular stressors, dryland salinity (Lewis 2003) and pesticide usage patterns (Chee Seng, pers. comm.). Other invertebrate groups have been suggested as potential indicators (spiders, grasshoppers and moths), but none are used in Australia for monitoring purposes.

2.6 Review of previous invertebrate monitoring programs in the Corangamite region

2.6.1 Introduction

As discussed, terrestrial invertebrate monitoring for ecosystem health and sustainability is largely in its infancy and therefore the number of research projects that have been conducted in the Corangamite Catchment on this topic are very limited. However, several studies have addressed some key aspects that are of major concern to the Corangamite Catchment region including salinity, biodiversity, pest management and revegetation. This section reviews six separate terrestrial invertebrate studies that have/are being conducted in the Corangamite CMA region. Some of these studies have been published in the scientific literature, whilst several are experimental studies presently being conducted at CESAR and the results are therefore preliminary.

Neville (2003b) surveyed invertebrates within different shelterbelt types to assess their biodiversity value, whilst Tsitsilas et al. (2006) survey invertebrates in shelterbelts and adjacent pasture to assess the effects of shelterbelt composition on invertebrate pests and beneficials. Lewis (2003) surveys invertebrates across a soil salinity gradient in a pasture environment and identifies groups that could be used as indicators of salinity stress. Neville (2003a) outlines and initiates a study for assessing the utility of invertebrates for indicating the success of revegetation programs. Gower et al. (2007) focus specifically on sustainable agriculture and the use of a particular insecticide spray strategy to control some of the major agricultural pests within cropping and pasture environments. Finally, Tsitsilas et al. (2007) investigate grass cover characteristics for enhancing biodiversity and sustainability in pastoral environments.

Each of these six studies is reviewed in detail where possible and the objectives, experimental design, sampling methods, results, analysis and interpretation are discussed. Most of these studies are aimed at sustainable agricultural and providing direct benefits to farmers. The final part of this section identifies some knowledge gaps, that if addressed, could assist in the utility of invertebrate monitoring in the Corangamite Catchment.

2.6.2 Neville (2003). Assessing the biodiversity value of invertebrates within shelterbelts

Neville (2003b) conducted a seasonal survey of invertebrates in 2002/3 at the Agroforestry for Salinity Control Trial (AFSCT) sites near Gerangamete (143° 69” E, 38° 46” S), 32 km south-east of Colac. The research project, funded by the Corangamite CMA, aimed to understand the link between shelterbelt composition and invertebrate biodiversity. Results were used to inform land managers on best practice for increasing invertebrate biodiversity when designing shelterbelts.


31 May 2007 Page 11

Shelterbelts are used throughout rural landscapes in Australia in response to the growing recognition of the potential role of trees in reducing land degradation, waterlogging and dryland salinity (Bird, Bicknell et al. 1992). Shelterbelts provide many inherent benefits to agroecosystems through shelter and protection to livestock, crops and pasture, and have also been shown to increase agricultural productivity (Nuberg 1998). Within the Corangamite Catchment, shelterbelts have been planted extensively in some regions. The AFSCT site near Gerangamete, including four farms, was initiated to combat the increasing salinity concerns throughout the region. These sites were established in the early 1990’s and shelterbelts planted varied in the number of rows, number of tree species, size, length and aspect. These trial sites provided a perfect opportunity to assess how these differences in shelterbelt composition might influence invertebrate biodiversity and therefore produce guidelines for the construction of shelterbelts to maximize biodiversity.

Project Objectives:

The shelterbelt invertebrate biodiversity project had several objectives:

1. To assess the invertebrate fauna within shelterbelts of different composition at the AFSCT sites.

2. To determine the optimal tree species composition, number of rows of trees and aspect that maximizes invertebrate biodiversity and hence beneficial invertebrates.

3. To assess the utility of two functional groups (ants and spiders) for assessing shelterbelt composition.

4. To compare the effects of native species versus introduced on invertebrate biodiversity

5. To develop guidelines for the construction of shelterbelts that maximizes invertebrate biodiversity.

While some of these objectives were met, only tentative conclusions were made for other objectives due to the limited number of sites.

Research Methods and Analysis:

Approximately 11 km of shelterbelts occur across the four properties involved in the AFSCT sites at Gerangamete (see Appendix 1 for trial site map). A total of 164 sampling points were randomly allocated throughout these shelterbelts on four occasions (autumn, winter, spring and summer). Additional sampling points were also allocated in remnant vegetation (40 samples) that adjoined the trial site and in two revegetated paddocks consisting of Eucalyptus trees (15 samples) or Casuarina trees (10 samples). The remnant vegetation and revegetated sites were used as control sites for comparison with the shelterbelt surveys. The shelterbelts were themselves classified into 11 different categories (see Appendix 1).

Samples were taken by two different methods at each sampling point. Pitfall traps (0.5 L plastic container, 80mm depth with ethyl glycol and 70% ethanol) were used to collect ground-dwelling ‘active’ invertebrates, whilst the beat method (Major, Christie et al. 2003) was used to sample from two branches immediately adjacent to the pitfall trap. Pitfall traps were left in the ground for 7 days, whilst beat sampling took place on the days immediately after pitfall traps were removed.


31 May 2007 Page 12

All invertebrates were sorted to Order following Harvey and Yen (1989) and CSIRO (1991), with some groups taken to the Family, Genus and even Species levels. Two groups (ants and spiders) were further classified into functional groups and analysed separately. Analyses mainly consisted of comparing average invertebrate densities between (a) seasons, (b) the different habitat types (shelterbelt, revegetated Eucalypt, revegetated Casuarina and remnant vegetation), and (c) the different shelterbelt types. Further analyses were also conducted on the influence of shelterbelt type on different groups/Orders of invertebrates for both pitfall and beat samples.

Results and Interpretation:

A total of 521,992 invertebrates were collected during the four sampling periods (autumn, winter, spring, summer). A large percentage of these were collembolans (437, 589) and were not included in subsequent analyses. The author states that there were seasonal differences in invertebrates, with the greatest number found in summer and spring. There were also differences between habitat types for both collection methods (pitfall and beat samples). Comparisons were then made between the different shelterbelt types (Appendix 1), with the following general recommendations made to enhance invertebrate diversity:

1. Native species are preferred to introduced species, with a far greater invertebrate biodiversity in shelterbelts with native species

2. Shelterbelts should consist of five rows of trees

3. Shelterbelts should include a minimum of three tree genera (including Eucalyptus, Acacia and either Melaleuca or Leptospermum)

4. Shelterbelts should try and include tall trees, understorey trees and shrubs to increase complexity and hence invertebrate diversity

Conclusions:

The data from the AFSCT sites at Gerangamete suggest that certain combinations of native trees are best for promoting biodiversity. The analysis was limited by the overall design and replication and the lack of an adequate control site. Findings suggest that introduced tree species (cypress) do not promote biodiversity. Further work understanding the link between shelterbelt design and biodiversity would be best served by incorporating multiple locations in the design and assessing biodiversity on a temporal scale, as well as having adequate controls in each location. The findings here suggest that future studies could focus on spiders as a functional indicator species. Ant functional groups, however, did not respond in this study suggesting there use may be limited.

2.6.3 Lewis (2003). Can invertebrates be used as indicators of dryland salinity? The identification of candidate assemblages in south-western Victoria

Lewis (2003) surveyed invertebrate fauna across a salinity gradient at the AFSCT sites near Gerangamete during 2003. The research project was designed to test the hypothesis that invertebrates could be used as a sensitive indicator of dryland salinity. This project was funded partially by the Corangamite CMA and CESAR.


31 May 2007 Page 13

Dryland salinity is of major concern to Australian agriculture with over 5.7 million hectares of agricultural land assumed to be at threat (NLWRA 2001). Assessment of dryland salinity is usually performed by remote sensing, electroconductivity characterization of soils or ground water monitoring, but these detection methods often only detect an impact once the biological tolerance of crops or pastures to salt have been exceeded (Sinclair and Hoffmann 2003). Therefore, the development of a sensitive indicator of dryland salinity would provide land managers with options prior to impacts being felt. The Corangamite Catchment is one of the worst affected regions for dryland salinity in Victoria and such early warning indicators would assist the Corangamite CMA in developing management strategies to combat the growing threats of dryland salinity. This would also feed into the CCMAs RCS targets for Sustainable Agriculture.

Project Objectives:

The project set out to explore the response of invertebrates to dryland salinity in agricultural environments and therefore provide a role in assisting farm-based management decisions. As stated in Lewis (2003), the project objectives were:

1. Determine whether invertebrate community composition responds to soil salinity in an agricultural environment.

2. Test the response of ants to indicate habitat complexity and soil conditions.

3. Determine whether invertebrate rapid assessment techniques, specifically the use of ordinal data, can detect environmental heterogeneity in an agricultural environment.

4. Assess the utility of the ‘Indicator Value Method’, and its implications for invertebrate monitoring in agriculture.


The same study site was used as in Neville (2003b) at the AFSCT sites near Gerangamete. Four transects were used to sample invertebrates; two transects traversed perennial pasture stocked with cattle, one transect traversed a five row shelterbelt and the last transect spanned a ten row shelterbelt. Tree species in the shelterbelt transects consisted of Eucalyptus occidentalis (3 rows), Casuarina glauca (1 row) and Melaleuca halmaturorum (1 row) for one transect and for the other transect Eucalyptus occidentalis (2 rows), E. spathulata (2 rows), E. gomphocephala (2 rows), Casuarina glauca (2 rows) and Casuarina cunninhamiana (2 rows).

Two sampling techniques were applied in this study, (a) pitfall trapping using a minor modification to the method of Majer (1978), and (b) beat sampling in transects with trees using the method of Major et al. (2003). For pitfall traps, along each transect 14 sampling points were established at distances between 25 and 50 metres, with 3-5 replicates/sampling point (a total of 196 pitfall traps). For beat samples, two eucalypts and one Casuarina were sampled in one transect, while in the other transect three Casuarinas and two eucalypts were sampled (each sample consisted of a combined catch from two branches). Samples were taken on three occasions (summer, autumn and winter), with pitfall trapping taking place over a period of seven days and beat samples taken on the days immediately after pitfalls were removed. Invertebrates were identified to Order using the key of Harvey and Yen (1989) and ants were identified further to the genus level. Measures of EC (soil salinity), pH and soil


31 May 2007 Page 14

fresh and dry weights were also taken in summer and winter samples. Finally, several measures of habitat heterogeneity were made (e.g. vegetation cover, bare ground, and leaf litter).

A number of non-parametric tests were used to assess the impact of several variables on the number and composition of invertebrates collected from pitfall and beat samples. To determine if EC was the explanatory variable amongst the set of environmental variables measured for differences in invertebrate diversity, step-wise multiple regression and correlations were computed to quantify the effect of each parameter. The suitability of each Order (or Genus for ants) as an indicator of soil EC was assessed using the ‘Indicator Value Method’ of Dufrene and Legendre (1997).


The author found significant differences between some invertebrate orders in the two different habitat types (pasture transects versus shelterbelt transects). The reasons for the patterns were not clear and may reflect species-specific responses.

The results suggested clear impacts of dryland salinity on invertebrate orders. Three orders responded to the salinity gradients; spiders, beetles and hymenopterans. All three showed high indicator values for salinity. There were seasonal differences in response, however, with these orders not showing an association in the autumn and winter samples. This may reflect that soil EC was only measured during summer and assumed to be similar in autumn and winter. Therefore the non-association may merely reflect this assumption.

The ant functional groups did not respond to EC and therefore are unlikely to be a useful indicator of soil salinity.

Conclusions:

The invertebrate survey conducted by Lewis (2003) across salinity gradients at the AFSCT sites was able to identify several invertebrate groups that could be used as indicators of dryland salinity. This is the first study that has tried to link changes in invertebrate density to salinity. This is a very important finding for Australia given the high rates of dryland salinity experienced across this country. There are several limitations of the study that warrant further investigation. Firstly, it is imperative that these results are extended both temporally and spatially as different soil properties may influence these groups as bioindicators. Secondly, taking the surveys to lower taxonomic levels (such as species) will allow greater resolution of the sensitivity of these groups and could help establish casual mechanisms (i.e. salinity) with greater authority.

2.6.4 Neville (2003). Assessing succession and biodiversity of invertebrates within revegetation areas: Apollo Bay revegetation project

In Australia, the use of invertebrates (and in particular, ants) as indicators of successful revegetation has primarily focused on the rehabilitation of old mine sites. The project undertaken by Neville (2003a) aimed to extend this work and develop invertebrate indicators for pastoral land rehabilitation. The initial sampling was funded by the Corangamite CMA and CESAR and the sites were located along the Great Ocean Road, near Apollo Bay.


31 May 2007 Page 15

Project Objectives:

The project set out to observe the succession of invertebrate biodiversity at five sites along the Great Ocean Road, Victoria. The main objectives of Neville (2003a) were to:

1. To observe the succession of invertebrate fauna through time on revegetated farmland

2. To document changes in biodiversity as revegetation develops.

3. To compare and contrast methods of revegetation (eg. direct seedling versus plantings of seedlings).

4. Develop indicator invertebrate groups that can be used by land managers and the Corangamite CMA to assess the progress of revegetated sites.

Research Methods and Analysis

Five sites were identified by the Corangamite CMA in the Apollo Bay region that included (a) a south facing revegetation site, (b) a north facing revegetation site, (c) a partially forested site, (d) a remnant native vegetation site, and (e) a ‘directly seeded’ revegetation site.

At each site, Pitfall traps (pitfall trapping using a minor modification to the method of Majer (1978)) were used to collect ground-dwelling ‘active’ invertebrates. Three samples, each consisting of 10 Pitfall traps, were made at each site. Pitfall traps were left in the ground for 7 days. Samples were collected in Spring 2002 and Autumn 2003, immediately prior to and following the revegetation treatments.


ES Link Services, in conjunction with CESAR, have identified to Order all invertebrates collected in the initial samples taken by Neville (2003a) in spring and autumn of 2002/03. A second collection has been made at the 5 sites in autumn of 2006 by CESAR/ES Link Services. These samples await identification to Order level. A spring sample will also be taken from the 5 sites in 2007. Analysis and interpretation will follow once samples have been identified and indicator invertebrate taxa will be selected.

Conclusions:

While Neville (2003a) undertook the initial sampling of invertebrate fauna, this project cannot be completed unless follow up sampling is undertaken so that the succession of invertebrate fauna can be identified. ES Link Services and CESAR, in conjunction with the Corangamite CMA have undertaken a follow up project to reassess the invertebrate fauna at the five revegetated sites originally sampled by Neville (2003a) and following the same sampling design. Although there are some limitations to the design of this study (primarily the lack of replication of treatments and statistical power), it is expected that ‘potential’ indicator invertebrate groups can be identified. These ‘potential’ indicators could then be trialled at other revegetated sites to see if they can be used more generally as indicators of health in revegetated pastoral sites.


31 May 2007 Page 16

2.6.5 Tsitsilas et al. (2006). Shelterbelts in agricultural landscapes suppress invertebrate pests

The role shelterbelts play in reducing land degradation, waterlogging and dryland salinity is clearly defined in Australian agriculture (Bird, Bicknell et al. 1992). Often, however, convincing land managers to allocate more productive farmland to shelterbelts is difficult because the benefits are not immediately seen. In addition, although never scientifically quantified, shelterbelts are inferred to be a source of pest invertebrates and weeds. The research project undertaken by Tsitsilas et al. (2006) aimed to understand how shelterbelts influence the number of invertebrate pests and predators within shelterbelts and in adjacent pasture. The results would provide land managers with the first quantitative assessment and help clarify any misconceptions.

Project Objectives:

Tsitsilas et al. (2006) identified two types of established shelterbelts, those with a ‘complex’ understorey consisting of tall and high grass cover, and those with a ‘simple’ understorey consisting of short or low grass cover. These shelterbelt types typify different management regimes (grazed or burnt versus unmanaged). The objectives of the Tsitsilas et al. (2006) research project were:

1. Do shelterbelts provide a haven for pests and assist recolonising of pasture in the winter and spring?

2. Do the higher numbers of invertebrate predators found in the shelterbelts have an impact on invertebrate pest numbers in adjacent pasture?

3. Do different characteristics of shelterbelts influence invertebrate pest and predator numbers?

The research combined field invertebrate surveys in the Corangamite, Glenelg-Hopkins and North Central CMAs and laboratory manipulation experiments.


Surveys conducted by Tsitsilas et al. (2006) found that shelterbelts within western and central Victoria generally fell into 1 of 2 categories depending on the nature of fencing around the shelterbelts; ‘complex’ which consisted of an understorey of grass that was dense and high, and ‘simple’ which consisted of an understorey of grass that was short and often sparse (see figure 3). They sampled the invertebrate fauna from 25 shelterbelts in four regions (Gerangamete, Streatham, Hamilton and Bendigo) in winter 2004, when pasture pests are known to be active. At each shelterbelt, two transects were set up, perpendicular to the shelterbelt-pasture border. There were 5 sampling points along each transect, starting in the shelterbelt and extending out 50 metres into the adjacent pasture.


(a) (b)

Figure 3 - Shelterbelts within western and central Victoria generally fell into one of two categories (a) those termed ‘complex’, which had dense undergrowth typified by thick and tall grass, and (b) those termed ‘simple’, which had short and sparse grass cover.

Invertebrate fauna were sampled along each of these transects using a “Weedeater” vacuum with a 100 µm fine cup sieve fitted on the end to prevent loss of invertebrates. All collections were initially sorted to Order; key pests (the red legged earth mite, Halotydeus destructor; blue oat mites, Penthaleus species; and lucerne flea, Sminthurus viridis) and beneficial invertebrates were then sorted to lower levels with two groups of key predators identified (predatory mites and spiders). At each sampling point, several key characteristics of the vegetation were also measured.

Glasshouse trials were used by Tsitsilas et al. (2006) to assess whether predators found within a shelterbelt and in the adjoining pasture could have a negative impact on earth mite (the main pasture pest, see figure 1) abundance. Closed mesocosm experiments containing pasture habitat and following the design of Umina and Hoffmann (2003) were utilized to test this hypothesis. Briefly, earth mites were collected from a pasture site at Mortlake (Glenelg-Hopkins CMA) and added to the mesocosms. Invertebrate predators collected from a ‘complex’ shelterbelt and adjoining pasture at the same site were then counted and introduced into the mesocosms. Appropriate controls were also included and two weeks after the introduction of predators, all remaining earth mites were counted within the mesocosms.

A variety of parametric and non-parametric statistical procedures were used by the authors to assess the relationships between the number of pests (earth mites and lucerne flea) and predators in and adjacent to the different shelterbelt types, controlling for vegetation characteristics at each sample point. Nested mixed ANOVAs (analysis of variance) were finally used to test differences within each region. The authors used one-way ANOVAs and correlation analyses to look for differences and associations between earth mite numbers and predators in the glass house mesocosm experiments.


The authors found that shelterbelt characteristics influenced the number of pest organisms in adjacent pasture. Lower numbers of pests in pasture adjacent to shelterbelts with tall (complex) grass were observed across different sites and regions (see figure 4). In addition, these shelterbelts carried low numbers of pest species, but higher numbers of predatory mites and spiders. The glass house mesocosm experiments suggested that the low number of pest species associated with complex understorey is likely to be a consequence of higher predator numbers; there was a marked reduction in pest earth mite numbers when predators were obtained from the shelterbelts compared with pasture.

31 May 2007 Page 17


Figure 4 - Number of pest species (red legged earth mites, blue oat mites and lucerne flea) in windbreaks

and in adjoining pasture. Transect points are marked as negative when extending into the windbreak and positive when extending into the adjacent pasture. Closed squares and solid lines represent data from simple shelterbelts, crosses and dashed lines represent data from complex shelterbelts. Vertical bars represent the standard errors for transect points.

Conclusions:

The results suggest a direct benefit of shelterbelts on pasture productivity, namely the reduction in pest pressure which is inferred to lead to an increase in plant and animal productivity. However, the benefit is only found when shelterbelts are managed in a particular manner; they need to be fenced and ungrazed. It is likely that these results will extrapolate to cropping environments, although this would

31 May 2007 Page 18


31 May 2007 Page 19

need to be tested. This is an important result because it provides an added benefit to shelterbelts which impacts directly upon productivity. However, the result needs to be dissected further to investigate what it is about shelterbelts with tall grass that provides these benefits (see 2.6.7 below).

2.6.6 Gower et al. (2007). Effectiveness of spring spraying targeting diapause egg production for controlling red legged earth mites and other pests in pasture

Along with land degradation, one of the largest environmental burdens caused by agriculture is the intense use of chemicals for the control of pests such as weeds and invertebrates. In pasture environments, red legged earth mites, blue oat mites and the lucerne flea are widely considered the most damaging invertebrate pests (see figure 2), reducing available feed for livestock. An insecticide based strategy known as Timerite® (Ridsdill-Smith and Pavri 2000) has been developed as a method to control these pests, but an extensive evaluation of this method in eastern Australia has not been undertaken. Gower et al. (2007) undertook a 2-year study of this method for controlling pasture pests at five sites in Victoria from 2003 - 2005 to assess its effectiveness. This study is important for sustainable agriculture as any insecticide based strategy will bear an environmental burden for land managers and the Corangamite Catchment.

Project Objectives

The main objectives of this project were:

1. To investigate the impact of spring spraying on red legged earth mite numbers throughout two growing seasons

2. To determine the effect of spring spraying on the other major pasture pests, the blue oat mite, the lucerne flea and aphid species

3. To assess the impact of the spring spraying strategy on beneficial invertebrates

Research Methods and Analysis

Paddocks at five sites in Western and Central Victoria (two within the Corangamite Catchment) were split into half and sprayed with a pesticide on one randomly allocated side using the TIMERITE® spray date for each location. Sampling of invertebrates was carried out along three transect lines running perpendicular to the boundary between the sprayed and unsprayed areas and 50 m apart. Ten samples were taken along each transect at regular intervals, five each in the sprayed and unsprayed areas. Mites were sampled six times along transects at each site over a 24 month period with the first sample taken immediately before the first spray date. Spraying occurred on the TIMERITE® date at each site for both years and sampling was performed using the ‘core’ method of Weeks and Hoffmann (2000).

In addition to the sprayed half paddock design, the authors also performed the same experiment in field mesocosms to eliminate mite movement from impacting on the study. Enclosed mesocosms were set up using corflute sheeting (inserted into the ground) with plots 2 m x 2 m in size. These exclusion plots prevent adult mites or their eggs moving into the plots. Ten plots were set up at


31 May 2007 Page 20

Winchelsea in Victoria, and five were randomly sprayed as above on the TIMERITE® date in 2003 and 2004. Mites were sampled six times as above using the ‘core’ method.

To examine the effect of spraying and location on the density of mites and other potential pests, two-way ANOVAs were carried out on data from each of the sampling periods. For the field enclosures, one-way ANOVAs were carried out testing the effect of sprays on mite density. In all cases invertebrate density data was log transformed prior to analysis.


The results from Gower et al. (2007) show that the Timerite® strategy is effective at suppressing red legged earth mites at the autumn break (70-90% control) but that the effect does not last through the winter growing season (figure 5). They suggest that whilst control may be of sufficient duration to facilitate plant establishment (annual clovers and grasses in the case of pastures), the lack of control in the latter half of the season necessarily means that spring spraying would need to be carried out annually. Interestingly, red legged earth mite numbers actually increased at some sites in sprayed plots compared to unsprayed, indicating that there are some synergistic effects of the spray which promotes rapid increases in the earth mites.

The Timerite® strategy had no consistent impact on the suppression of blue oat mites, lucerne flea or aphids. This strategy therefore has limited appeal as a general method to suppress invertebrate pests in pasture environments.


late season 2003

(pre-spray)

0

1000

2000

3000

4000

num

ber p

er s

q. m

etre

autumn break 2004

020004000

60008000

mid season 2004

0

500

1000

late season 2004

01000

20003000

4000*

autumn break 2005

0

200

400

600

late season 2005

0

200

400

*** **

**

0

200

400

sprayed

unsprayed

Figure 5 - Comparison between sprayed and unsprayed treatments on numbers of red legged earth mites after correction for location differences

Conclusions:

The Timerite® strategy was developed by CSIRO researchers in conjunction with Australian Wool Innovation as a method for controlling the important pasture and crop pest, the red legged earth mite. However, this strategy has never been rigorously tested in the field using quantitative assessment methods. Gower et al. (2007) provide such tests at five pasture sites in Victoria. The results have immediate impact on the usefulness of this approach to the control of red legged earth mites and other pasture pests. It is suggested from their research that this method only has limited success in controlling pasture pests and that the benefits do not last throughout a growing season. The method inherently promotes continual spraying to achieve adequate control of red legged earth mites. Further research should look at integrating this strategy with a ‘soft’ chemical that does not harm other invertebrates in the system, so that the initial benefits of protecting emerging seedlings are gained without the loss in biodiversity.

31 May 2007 Page 21


31 May 2007 Page 22

2.6.7 Tsitsilas et al. (2007). Grass cover characteristics and their effects on beneficial organisms and pests in adjacent pasture.

Following their previous results (see 2.5.6), Tsitsilas et al. (2007) have undertaken an experiment that further dissects the importance of grass height on pest and beneficial invertebrates in shelterbelts and adjacent pastures. This experiment is currently in progress and therefore results are only preliminary.

Project Objectives:

There is only one objective for this research project:

1. To directly manipulate grass height within shelterbelts and document the impact that this has on the number of invertebrate pests and beneficials in the shelterbelt and adjacent pasture.


Three shelterbelt sites (two in Glenelg-Hopkins Catchment and one in Corangamite Catchment) at least 120 m in length were selected for tall and dense grass cover in 2006. At each site during winter, alternating 20 m strips of ‘complex’ understorey (control areas) and ‘simple’ understorey (generated by mowing to a height of 5 cm and raking grass) were constructed (three repeats of each treatment). In August, five samples of invertebrate fauna per strip (60/site) were taken using a blower vacuum as in Tsitsilas et al. (2006). A further five samples were taken directly perpendicular to each sample point 10 metres into the pasture. A total of 60 samples were taken from each site and sorted first to Order. Pest invertebrates and key predators were then identified to lower levels. Sampling of all sites was again conducted in September.

While all samples have now been sorted, only descriptive analyses have been performed thus far.


Only preliminary assessment of the data has been made, with no formal statistics quantifying the effects found by the authors. Figure 6 shows the general effect found across sites. The number of earth mites is greatly increased in the mown (‘simple’) shelterbelt and adjacent pasture compared to the control (‘complex’) shelterbelt and pasture adjacent to it. The number of predators, however, was far greater in the ‘complex’ shelterbelt and adjacent pasture. No formal interpretation of this data has been made as yet.


31 May 2007 Page 23

Red legged earth mites in manipulated windbreak and adjacent pasture

0

4000

8000

12000

Control Mow n and raked

Num

bers

per

m2

Windbreak

Pasture

Mesostigmatic predatory mites in manipulated windbreak and adjacent pasture

0

250

500

750

1000

Control Mow n and raked

Num

bers

per

m2

Windbreak

Pasture

Figure 6 - The number of (a) red legged earth mites in manipulated windbreak and adjacent pasture, and (b) mesostigmatic predatory mites in manipulated windbreak and adjacent pasture.

Conclusions:

While no formal analyses have been performed for the above data, it appears clear that you can manipulate grass height within shelterbelts and get dramatic effects on the number of pest and predator invertebrates within the shelterbelt and out into adjacent pasture. These results clearly indicate that the benefits found in Tsitsilas et al. (2006) are largely due to grass height within shelterbelts. This is a very important finding and has wide implications for sustainable agriculture within Australia. These findings also indicate that it may be possible to plant grass strips within pastures and/or cropping environments and enjoy the benefits of pest invertebrate suppression shown here.

2.6.8 Summary

There are four key findings from the above terrestrial invertebrate monitoring projects which have important implications for the Corangamite Catchment and the broader Australian landscape:

1. Some invertebrate taxa are affected by salinity gradients and could potentially be sensitive bioinidicators of dryland salinity.

2. Shelterbelts increase beneficial diversity which can suppress important invertebrate pests within adjacent pasture.

3. The widely used spring spraying strategy known as Timerite® for the control of earth mites is not effective throughout a growing season and may in fact increase pest pressure.

4. Grass cover characteristics could provide endemic control of invertebrate pests of pasture.

These findings could have large impacts on sustainability within agricultural ecosystems in the Corangamite Catchment and improve overall health of the region.


31 May 2007 Page 24

2.7 Knowledge gaps in invertebrate monitoring in terrestrial environments

Due to the relative infancy of invertebrate monitoring in terrestrial environments compared with aquatic monitoring, there are many areas that need further investigation. It is clear from studies in Australia and abroad that invertebrates can be used routinely for indicating habitat restoration (Andersen, Fisher et al. 2004; Hodkinson and Jackson 2005) or revegetation succession. Studies conducted at CESAR in the Corangamite Catchment and other regions in Victoria also show directions for land managers to attain more sustainable agricultural practices by reducing invertebrate pest pressure and the reliance on chemicals. But there are several key knowledge gaps that are apparent from this review that are pertinent to the Corangamite Catchment:

• Bioindicators for soil health and the identification of nutrient deficiencies

• Extending the work of Lewis (2003) to develop robust indicators of dryland salinity and determine their sensitivity

• Develop multivariate approaches to understanding the links between invertebrate biodiversity and pollutants/nutrient deficiency

• Determine the inherent characteristics of shelterbelts or grass cover that promote invertebrate predators

• Key indicator groups and a framework that can be utilized by land managers to give an indication of sustainability

One methodological issue with invertebrate biomonitoring in the Corangamite Catchment and Australia in general is the concern of the level of invertebrate identification. Sorting by orders, represents the simplest approach, and has often been applied in invertebrate monitoring programs in the Corangamite Catchment, but lower level sorting to families, genera or species is likely to be required. This presents a technological challenge as this is a time consuming process and often requires specialist taxonomists. The advent of recent molecular biology DNA technologies may help in this regard in the future by developing assays that can determine species without expert knowledge.

Note: For sustainable production in agricultural systems, the work of Thomson and Hoffmann (2006) highlights an important concept that could have immense value to the Corangamite Catchment. Their framework for assessing the impacts of chemicals at the farm level (in vineyards) on biodiversity is pioneering work and a similar framework should be considered for other agricultural industries, particularly for promoting sustainable agriculture.

2.8 Conclusion Terrestrial invertebrate monitoring has many benefits over other biological indicators for indicating health in the Corangamite Catchment. However, the relative infancy of this emerging field, combined with the general lack of taxonomic expertise, has held back its applicability to date. In Australia, numerous invertebrate groups have been evaluated for their potential as indicators of terrestrial environments. The ants are considered the most likely candidates for assessing habitat disturbance and change, and some believe they can be used as a general indicator of environments (Andersen,


31 May 2007 Page 25

Fisher et al. 2004). Their use has been made somewhat easier by the simplification of identification into functional groups. But will these be a general indicator group within Australia? Recent results suggest that they do not respond to particular environmental stressors (Lewis 2003); Chee Seng, pers. comm.) and therefore that they may be limited to more generalized scenarios such as broad scale habitat disturbance and the regeneration of habitats (eg. mining site rehabilitation). Future research needs to consider other groups when assessing particular environmental stressors and this may mean focusing on more than one group of invertebrates.

While the number of terrestrial invertebrate monitoring studies conducted in the Corangamite Catchment is low, several interesting results have been found. The project initiated by Neville (2003a) promises to provide some insight into the succession of invertebrate taxa following revegetation. This monitoring program will identify all invertebrates sampled and thus it will be interesting to compare the responses of ants to other groups. This project should provide the Corangamite Catchment with invertebrate indicators for monitoring revegetation programs.

Several projects have made a direct link between habitat management, invertebrate diversity and agricultural sustainability. This is particularly important for the Corangamite CMA due to the large amount of agricultural land within this region. The work on shelterbelts is particularly exciting as it provides an environmentally friendly and sustainable way of controlling invertebrate pests of crops and pastures. It also could help to alleviate one of the major pollutants in agricultural systems, the use of pesticides. Recommendations can now be made by the Corangamite CMA on shelterbelt composition and management that will increase biodiversity and lower invertebrate pest pressure. These recommendations will help promote sustainable agriculture within the Catchment. Further research is still needed to determine the direct role that the understorey plays in increasing beneficial predators. If grass characteristics are the most important component, then it may be possible to provide additional benefits by planting tall grass strips through cropping and pasture paddocks.

In aquatic environments, invertebrates are being used as biotic indices for particular pollutants and/or environmental stressors (see below), which is the ultimate aim of all invertebrate bioindication studies. Few studies in Australia have, however, succeeded in developing biotic indices for invertebrates in terrestrial environments. Thomson and Hoffmann (2006) provide one of the few instances where invertebrates have been used to develop biotic indices for pesticide use in an Australian farming environment. While this innovative approach still needs to be extrapolated to other farming systems, the research suggests that CMAs may be able to classify the impact that particular farming practices (in this case, pesticide usage) have on the environment. Lewis (2003) has also shown that several groups of invertebrates have the potential to be used as indicators of dryland salinity, although the data is only preliminary and needs to be extrapolated over a wider area.

Clearly invertebrates can be used successfully to monitor terrestrial environments. There continued development as indicators, however, relies on further research directed at specific questions and the testing of monitoring programs by land managers. Developing indicator systems that can be used by non-specialists is also a goal that researchers must strive to achieve.


31 May 2007 Page 26

3 INVERTEBRATE MONITORING IN AQUATIC FRESHWATER ENVIRONMENTS

3.1 Introduction Biological methods are now extensively integrated into water quality monitoring programs worldwide. Biological communities form an important part of field-based water quality monitoring as they reflect all types of pollutants and disturbances by taking into account antagonistic or synergistic effects, inadequate habitat, introduced species or fluctuating water volumes (Maher and Norris 1990). In contrast, physico-chemical monitoring may miss intermittent inputs and flood events, and may not describe all potential environmental stressors or be ecologically relevant. However, biological monitoring programs generally rely on the collection of complimentary physico-chemical information: while biological communities can indicate the effects of environmental stressors on ecosystem condition, physico-chemical information is useful in determining possible causative agents (Bunn 1995; Norris and Thoma 1999).

Biomonitoring methodologies for freshwater systems have included examining changes in community structure of a wide variety of organisms. Fish, periphyton, macrophytes and zooplankton have all been suggested as potential bioindicators of water quality. However, monitoring benthic macroinvertebrates is the most widely adopted methodology (Resh, Norris et al. 1995). Benthic macroinvertebrates are favoured bioindicators because they are diverse, abundant and occur in all aquatic habitats. They are typically sedentary and therefore reflect local conditions, and they exhibit a broad range of sensitivities to various toxicants and disturbances. Macroinvertebrates can be easily collected and identified (to Family), can respond quickly to environmental stressors and serve as a primary food source for fish and other vertebrates, thus they provide strong information for interpreting cumulative effects. A rapid bioassessment protocol has been developed for benthic macroinvertebrates for assessing aquatic environments (Chessman 1995; Resh, Norris et al. 1995). This protocol was developed to standardize the collection of macroinvertebrate data and enable the subsequent comparison of macroinvertebrate assemblages between sites over broad temporal and regional scales. Macroinvertebrates collected using the rapid assessment protocol are commonly identified to Family level and the data is analysed to assess ecosystem condition using biotic indices.

3.2 Current monitoring programs in Australia In the past decade, water quality monitoring in Australia has been supplemented with biological methods, with benthic macroinvertebrates the preferred biological indicators (Davies 2000). Broad-scale assessment approaches, such as rapid bioassessment protocols (RBP) using macroinvertebrates, are commonly used as a ‘first-pass’ to determine whether there are problems and their extent. The most widely used broad-scale bioassessment approach in Australia is the Australian River Assessment Scheme (AUSRIVAS). AUSRIVAS is based on the UK RIVPACS predictive model (Wright, Armitage et al. 1989) and contains region-specific models for determining the quality of rivers and streams. This predictive approach uses a set of minimally or unimpacted reference sites, which characterize the biological condition of a region. A test site is then compared to an appropriate subset of reference sites to assess the level of environmental stress or impairment (Davies 2000). Advantages of using predictive models are they predict what taxa should occur, and therefore the amount of biodiversity lost at test sites. The models make no assumptions about the stressors affecting biota, and


31 May 2007 Page 27

they provide an easy means for water managers to perform assessments against clearly defined predictions (Norris and Hawkins 2000).

The biotic index or SIGNAL (stream invertebrate grade number – average level) scores are calculated along with AUSRIVAS scores to provide a second measure of impairment. Biotic indices operate by grading macroinvertebrate families for their sensitivity to pollution and other anthropogenic disturbances (Chessman and McEvoy 1998). SIGNAL assigns scores for common families from 1 (the most pollution-tolerant families) to 10 (the most pollution-sensitive families) and an index is generated for a test site by averaging the grade scores (Chessman 1995).

The AUSRIVAS program was developed under the National River Health Program funded by the Australian Federal Government in 1994. The goal of this program was to provide a comprehensive assessment of the health of inland waters which could form a baseline for future monitoring as well as identify key areas for the maintenance of aquatic and riparian health and biodiversity, and identify stressed inland waters. The program was carried out by the Environment Protection Agency (EPA) and concluded in 1999. Subsequent macroinvertebrate sampling across Australia has continued at a much reduced level, entirely supported by the EPA and only reference sites are currently being sampled. It is not known if the Federal government will support another complete rivers audit under this program throughout inland Australia, including the Corangamite Catchment.

At the state level, the Victorian River Health Program uses the Index of Stream Condition (ISC) to monitor the health of Victoria’s rivers. The ISC uses five key components to assess river health (hydrology, water quality, streamside vegetation, physical form and aquatic life). The aquatic life component utilizes the AUSRIVAS and SIGNAL indicators. The ISC is assessed every five years, with assessments conducted in 1999 and 2004.

3.3 Recent innovations in invertebrate monitoring in aquatic environments

Biological assessment of aquatic ecosystems using Family-level macroinvertebrate (i.e. AUSRIVAS) identification may assist in understanding the degree of impairment of a river system, but often lacks the sufficient resolution to identify those stressors having greatest impact on the biota. Species level identification however, may provide the resolution to be able to link specific species responses with particular environmental stressors. CESAR is currently developing a program that investigates the use of species-specific bioindicators to identify actual pollutants in urban aquatic environments.

Previous studies have shown the utility of chironomids (midges) as bioindicators of aquatic degradation and pollution (e.g. Bahrndorff, Ward et al. 2006). They represent a large proportion of the total abundance and taxonomic diversity of most aquatic invertebrate communities. However, their use has been hampered by difficulties with identification of species life stages (larvae, pupae) and morphologically cryptic species. They have therefore been given minimal attention in the Australian Rapid Bioassessment monitoring programs because, at the family level they show no response to pollution and are generally considered to be tolerant.

CESAR has recently developed a novel molecular protocol for the rapid identification of chironomid species (Carew, Pettigrove et al. 2003; Carew, Pettigrove et al. 2005). Together with Melbourne Water, this has allowed a large scale assessment of chironomid species as bioindicators of water quality within urban aquatic environments. Combined with water quality measures and a novel microcosm method for assessing the effects of stressors on chironomid species (Bahrndorff, Ward et


al. 2006), the results have shown clearly that some chironomid species are sensitive/tolerant to particular stressors, such as heavy metal pollutants, pesticides and, importantly, salinity. This is despite higher taxonomic levels showing no response (Figure 7; taken from Carew 2006). Appendix 3 lists numerous Chironomid species shown by Pettigrove (2006) to be sensitive to particular stressors using the microcosm approach. Chironomid species are therefore sensitive bioindicators of particular stressors and can be used to develop a biotic index of water pollution.

a)

Autumn 2003

010002000300040005000600070008000

All Tanytarsus species T. semibarbitarsus

Elec

trica

l con

duct

ivity

(uS/

cm)

absent

present

b)

Spring 2003

05

1015202530

All Tanytarsus species T. inextentus

Cop

per m

g/kg

absentpresent

31 May 2007 Page 28


c)

Spring 2003

05

10152025

All Paratanytarsusspecies

P. grimmii

Nic

kel (

mg/

kg)

absentpresent

Figure 7 - Average levels of pollution at sites where species were present/absent compared to average pollution levels where the genus was present/absent.

3.4 Overview of previous monitoring programs in the Corangamite region

In 1994, the Australian Federal Government funded the National River Health Program (NRHP), which led to the development of the AUSRIVAS bioassessment protocol for assessing river health using macroinvertebrates. This program assessed over 2000 river sites throughout Australia during a 5 year period. In Victoria, approximately 199 ‘reference’ sites (used for the predictive models; Marchant, Hirst et al. 1999) have been sampled, with over 30 of these reference sites located in the Corangamite Catchment (Figure 8). The data that was accumulated during this 5-year study has been used to address many questions relating to the use of macroinvertebrates as indicators of water quality (e.g. Chessman 1995; Chessman and McEvoy 1998; Marchant, Hirst et al. 1999; Marchant, Wells et al. 2000). Several studies have since followed using the same rapid bioassessment protocols developed during this study. Table 1 lists 20 research projects that have been conducted on invertebrates in streams, rivers and lakes from the Corangamite Catchment over the last 15 years.

31 May 2007 Page 29


Figure 8 - Macroinvertebrate reference sampling sites in Victoria sampled between 1994 and1999. Numbers

represent interim biogeographic regionalization for Australia (IBRA) regions (1-11). Figure taken from Marchant et al. (2000).

Apart from the required sampling regime conducted under the NRHP (and associated analyses conducted by the EPA), most research within the Corangamite region has focused on one theme. Not surprisingly, salinity has been the major focus of invertebrate aquatic research in the Corangamite Catchment with over eight projects conducted in the last 15 years (Kahn 2003; Kefford 1996; Kefford 2000; Kefford, Palmer et al. 2005; Kefford, Papas et al. 2003; Kefford, Paradise et al. 2003; Metzeling, Perriss et al. 2006; Williams, Boulton et al. 1990). Surprisingly, however, while there appears to be a relationship between macroinvertebrate community structure in rivers and salinity (Kefford 2000; Metzeling, Perriss et al. 2006), no sensitive bioindicators have so far been developed that can be routinely used to assess salinity levels in streams, rivers and lakes.

N.B. For more specific details on these studies, please see the papers found below in the database attached to this report.

31 May 2007 Page 30


31 May 2007 Page 31

Table 1 - Macroinvertebrate studies that have been conducted (or sampled from some sites) in the Corangamite Catchment over the last 15-20 years. N.B. Some studies that were part of the NRHP are not shown due to the inability to determine the exact locations of sites within those papers.

Author(s) Title Year Type Kefford BJ The effect of electrical conductivity on selected

macroinvertebrates in four river systems of south western Victoria

1996 Report: DNRE Vic

Kefford BJ, Papas PJ, Nugegoda D Relative salinity tolerance of macroinvertebrates from the Barwon River, Victoria

2003 Journal Article: Marine & Freshwater Research 54: 755-765

Williams WD, Boulton AJ, Taafe RG Salinity as a determinant of salt lake fauna: a question of scale

1990 Journal Article: Hydrobiologia 197: 257-266

Chessman BC, McEvoy PK Towards diagnostic biotic indices for river macroinvertebrates


Enivronment Protection Agency Corangamite basin, spring 1994

1997 Report: EPA Vic

Kefford BJ, Paradise T, Papas PJ, Fields E, Nugegoda D

Assessment of a system to predict the loss of aquatic biodiversity from changes in salinity.

2003 Report: Land & Water Resources RDC

Metzeling L, Perriss S, Robinson D Can the detection of salinity and habitat simplification gradients using rapid bioassessment of benthic invertebrates be improved through finer taxonomic resolution or alternative indices?


Metzeling L, Tiller D, Newall P, Wells F, Reed J

Biological objectives for the protection of rivers and streams in Victoria, Australia


Jayawardana JMCK, Westbrooke M, Wilson M, Hurst C

Macroinvertebrate communities in Phragmites australis (Cav.) Trin. ex Steud. reed beds and open bank habitats in central Victorian streams in Australia


Robson BJ, Hogan M, Forrester T Hierarchical patterns of invertebrate assemblage structure in stony upland streams change with time and flow permanence

2005 Journal Article: Freshwater Biology 50: 944-953

Kefford BJ, Palmer CG, Nugegoda D Relative salinity tolerance of freshwater macroinvertebrates from the south-east Eastern Cape, South Africa compared with the Barwon Catchment, Victoria, Australia

2005 Journal Article: Marine & Freshwater Research 56: 163-171

Kahn TA Limnology of four saline lakes in western Victoria, Australia

2003 Journal Article: Limnologica 33: 327-339

Stilwell JD Macropaleontology of the Trochocyathus-Trematotrochus band (Paleocene/Eocene boundary), Dilwyn Formation, Otway Basin, Victoria

2003 Journal Article: Alcheringa 27: 245-275

Thomson JR The effects of hydrological disturbance on the densities of macroinvertebrate predators and their prey in a coastal stream


Wells F, Metzeling L, Newall P Macroinvertebrate regionalization for use in the management of aquatic ecosystems in Victoria, Australia

2002 Journal Article: Environmental Monitoring & Assessment 74: 271-294

Marchant R, Wells F, Newall P Assessment of an ecoregion approach for classifying macroinvertebrate assemblages from streams in Victoria, Australia

2000 Journal Article: Journal of the North American Benthological Society 19: 497-500

Hewlett R Implications of taxonomic resolution and sample habitat for stream classification at a broad

2000 Journal Article: Journal of the North American

http://www.epa.vic.gov.au/


31 May 2007 Page 32

Author(s) Title Year Type geographic scale Benthological Society 19:

352-361 Kefford BJ The effect of saline water disposal: implications for

monitoring programs and management 2000 Journal Article:

Environmental Monitoring and Assessment 63: 313-327

Marchant R, Hirst A, Norris R, Metzeling L

Classification of macroinvertebrate communities across drainage basins in Victoria, Australia: consequences of sampling on a broad spatial scale for predictive modelling


Quinn GP, Lake PS, Schreiber SG A comparative study of colonization by benthos in a lake and its outflowing stream


3.5 Knowledge gaps in aquatic monitoring programs using invertebrates

The ultimate aim of all aquatic biomonitoring programs is to develop a biotic index of water pollution that is specific for particular pollutants. In Australia, government agencies have adopted several biotic indices for assessing river health, namely the SIGNAL (Chessman 1995) and AUSRIVAS (Simpson and Norris 2000) indices. However, these programs are designed for low level taxonomic resolution (Family level identification) to reduce time and costs associated with collecting and processing. While this is adequate to describe the general condition of an aquatic system (river, stream or lake), it does not readily identify why a particular aquatic system rates poorly in comparison to reference sites. Nor does it act as an adequate early warning system because it is a relatively insensitive assessment of environmental stress. Finally, there is no establishment of cause and effect between the biota and a particular stressor, which makes it difficult to establish targeted management procedures.

The current models used in Australia serve a valuable purpose in that they can identify regions that are affected by pollution and/or other stressors relative to reference sites. However, biotic indicators that can identify the actual pollution and/or stress need to be developed. Accurate, targeted management decisions combined with early intervention can provide an immense saving to Governments, water bodies and CMAs. The development of specific aquatic invertebrate groups for this purpose, combined with rapid identification protocols, will facilitate the improvement of Australia’s waterways. Chironomids appear to be such a group and research needs to continue into their development as biotic indicators of pollution and stress.

3.6 Conclusion Invertebrate monitoring in aquatic environments in Australia is quite advanced. The need to improve the quality of Australian waterways has led to legislative changes that require invertebrate monitoring to be conducted (Simpson and Norris 2000). Using standards that have been developed in other countries and adapting them to Australian conditions, a simple Rapid Bioassessment approach has been developed. The Rapid Bioassessment technique requires identification of invertebrates only to the Family level. Using several measures (AUSRIVAS, key families) and indices (SIGNAL, EPT) an assessment of the health of a waterway or region can then be made. However, it is still difficult to pinpoint the actual contaminants or stressors within a water system and other knowledge is needed to make an informed decision. A recent approach promises to deliver bioindicators of particular stressors


31 May 2007 Page 33

in aquatic environments using a combination of novel approaches. By identifying species within the Family Chironomidae using DNA technologies and combining presence/absence data with tolerance/susceptibility data of pollutants/stressors from field microcosms, CESAR is developing a new biotic index for river health. While the current monitoring programs can give a coarse view of river health, these new biotic indices will be able to pinpoint actual pollutants and stressors allowing Governments, CMAs, water bodies and regulatory agencies to plan targeted management actions.


31 May 2007 Page 34

4 TOWARDS USING INDICATOR INVERTEBRATE SPECIES IN THE CORANGAMITE CATCHMENT

4.1 Introduction This section provides an overview of the broader management framework developed by the Corangamite CMA, into which an invertebrate monitoring program will be required to integrate. It includes an overview of the adaptive management approach, the required attributes of an invertebrate indicator, key Corangamite CMA issues (of potential relevance to invertebrate monitoring) and Corangamite CMA’s Monitoring and Evaluation Program.

4.2 The Adaptive Management Framework The Corangamite RCS and associated supporting strategies are based on an adaptive management approach which in broad terms provides a process in which resource condition targets are developed and against which the management actions to achieve those targets can be monitored and evaluated.

This approach is based on the National Framework for Natural Resource Management (NRM) Standards and Targets and the National Natural Resource Management Monitoring and Evaluation Framework (Natural Resource Management Ministerial Council, 2002). These protocols have been established to provide a consistent national approach to natural resource management and guide government investment into regional land and water management strategies most notably through the National Action Plan for Salinity and Water Quality and the Natural Heritage Trust.

CMAs are required to establish resource condition and management action targets in developing their regional strategies. Targets may relate to either an absolute improvement in resource condition or decreases in the rate of degradation and may be expressed as numbers or percentage changes. The National Framework presents a suggested process for establishing targets which is based on a wide consideration of the available social, economic and environmental data (See figure 9 below)


Figure 9 - Process for setting objectives and targets within regional plans and selecting a set of management actions to achieve them

The suggested approach to target setting recognises the potential for complex trade-offs between various competing values and conditions and therefore has a strong emphasis on the inclusion of a process for comparing the relevant costs and benefits of different scenarios. These include the use of management tools such as modelling, cost-benefit analysis and multi-criteria analysis which can incorporate a variety of subjective considerations.

The National Natural Resource Management Monitoring and Evaluation Framework has been established to provide a consistent national approach to reporting regional progress against their established resource condition and various management targets. The framework provides information on the state of a regions natural resources and the performance of the management approaches used to achieve targets. The Framework is based on a set of governing principles and suggested indicators for different components of natural resource management. Importantly, the framework emphasizes the reporting of community processes relevant to or affected by the regional NRM programs in addition to measures of sustainable development.

CMA’s are required to regularly report on progress towards achieving the goals and objectives of their RCS at a number of levels. Each CMA is required to produce an annual report for the Minister and Council which details the condition and management of land and water resources in its region and the carrying out of its functions. A “State of the catchment” report is also required by government every five years which details resource conditions, trends and associated measures using a range of indicators.

31 May 2007 Page 35


31 May 2007 Page 36

4.3 Integrating Invertebrate Indicators

4.3.1 Identification of an invertebrate indicator

Indicators are measurable attributes (biotic or abiotic) that can be used to monitor the condition of a natural resource, area or ecosystem (Dalal, Lawrence et al. 1999). They may be a single parameter or a combination of parameters that can be monitored by field sampling, field observation, remote sensing and geographical information systems, as well as existing information through data mining. The main purpose of an indicator, either by itself or in conjunction with other indicators, is the potential to influence a management choice.

Biological indicators, as their name suggest, possess the added benefit of being able to monitor the biological relevance of changes in an environment. Some changes, such as pollution, may have little impact on the biota that live within that environment and management decisions need to take this into consideration before taking action. Similarly, the sensitivity of some biological indicators may show an effect on biota within an environment prior to any physical or chemical property, and it is these indicators which are most important because they can lead to management decisions before impacts are felt at the economic, social or environmental level.

There are three classifications of biological indicators: (i) environmental indicators that reflect the biotic and abiotic state of an environment; (ii) ecological indicators that reveal evidence for, or impacts of, environmental change; (iii) biodiversity indicators that specifically indicate the diversity of species, taxa, or entire communities within an area. Environmental indicators are descriptive in that they indicate changes in the state of the abiotic environment directly. Ecological indicators differ from both environmental and biodiversity indicators in that they indicate functional change to systems. They demonstrate the effects of environmental change on the biotic systems including species, communities and ecosystems (McGeoch 1998; Meffe and Carroll 1994). Biodiversity indicators indicate the presence of a set of other species and are largely descriptive.

Having established that the best candidates as biological indicators are invertebrates (see chapters 2 and 3), how do we go about choosing the ‘best’ invertebrate biological indicator? The criteria for selection of bioindicator organisms have been detailed by many authors including Hellawell (1986), Pearson (1994),and McGeoch (1998). The prime generic criteria are:

1. Higher and/or lower taxa chosen have well-known and stable taxonomy, with ease of identification identified.

2. Biology of organisms is well known, particularly in response to stress factors or changes in habitat properties of interest.

3. Organisms are abundant, easily surveyed and manipulated.

4. Higher and lower taxa chosen are distributed on a scale that matches the spatial and temporal requirements of the study.

5. The chosen taxon or groups of taxa are representative of the whole community, or, if not, then their responses are strongly correlated with a known stress factor.


31 May 2007 Page 37

Additionally, another important factor should also be considered and that is the logistics and cost of biomonitoring and evaluation compared with alternative methodologies. The ideal system is inexpensive, simple, easy to implement, quick, reliable, and easily understood by non-professionals. This ideal clearly is hardly ever achievable, and any biomonitoring system is a compromise between precision and cost.

4.3.2 Integration with the Corangamite Regional Catchment Strategy

Corangamite CMA Vision 2003-2008

The 2003-2008 CCMA RCS acknowledges six key components to an overarching vision for the Corangamite region. Of the six areas (and associated broad goals) identified the following are considered relevant to the aims of this report:

Vision Component 1.1 – A Healthy Environment

“By 2020, the health of the environment will be improving in each landscape, including the marine environment, of the Region”.

Vision Component 1.2 – Sustainable Economic Use of Sustainable Resources

“By 2020, all enterprises will use resources in a way that maintains ecological processes”.

As previously discussed in this report, a number of invertebrate studies have been completed to inform the development of indicators and monitoring programs to ensure a healthy environment, and sustainable agriculture.

Corangamite CMA Asset Classes and Associated Threats

The Corangamite CMA RCS 2003-2008 categorises the region’s assets into three broad groups: economic, environmental, and social. Similarly, the threats (factors that reduce the services provided by assets) of the region have been broadly classified into biophysical threats and threats from society.

Following Table 20 (pg 73) of the RCS, a brief review of the asset groups and associated threats is provided below with a broad identification of the areas that have been linked to invertebrate monitoring or indicators by published studies (internationally peer reviewed studies).


31 May 2007 Page 38

Table 2 - Linking published studies on invertebrate indicators and monitoring to Corangamite RCS asset classes and threats.

Asset Key Threats Related invertebrate studies?

Economic Assets Water Use

Reduced Flow

Yes

Nutrients, Sediments Yes Salinity Yes Land Use Change, Land

Clearing Yes

Population Pressure Yes Land Use Salinity Yes Weeds - Pest Animals Yes Soil Deterioration Yes Land Use Change, Land

Clearing Yes

Poor On-ground Management No, but potential exists Inadequate Strategic

Management No

Infrastructure Disasters No, but potential exists Salinity Yes Environmental Assets

Coastal and Marine

Increased and Decreased Flow

No

Weeds and Pests - Poor On-ground Management No, but potential exists Land Use Change, Land

Clearing Yes

Population Pressure Yes Inadequate Strategic

Management No

Surface Water Reduced Flow Rates Yes Nutrients, Sediments Yes Salinity Yes Poor On-ground Management No, but potential exists Inadequate Urban/Industrial

Waste Yes

Vegetation Land Clearing, Poor Veg management

Yes

Weeds No Poor On-ground Management No, but potential exists Pest Animals Yes Land Use Change/Conflict Yes Knowledge Limitations No Inadequate Strategic

Management No

Inadequate Resources No


31 May 2007 Page 39

Asset Key Threats Related invertebrate studies?

Fauna Land Clearing, Land Use Change, Pest Animals

Yes

Inadequate Resources Yes Social Assets Community Inadequate Strategic

Management No

Limited Knowledge, Limited Human Capacity

No

Population Pressure No Land Use Change/Conflict No

4.3.3 Incorporating invertebrate indicators into the Monitoring and Evaluation Framework

The Monitoring and Evaluation Program for the Corangamite CMA RCS is directed by the “Monitoring and Evaluation Approaches for Natural Resource & Catchment Management in the Corangamite Region (July 2002)”. This document provides an overview on the development of indicators to be used to monitor a range of subject areas in the Corangamite CMA region related to natural resource management and regional sustainability.

The document provides details on the required components of an indicator monitoring plan which is a tool used to plan and manage the “collection, interpretation, analysis, reporting and use of selected indicators”.

The various sections required in an indicator/monitoring plan is presented as follows:

1. Indicator title

2. Indicator description

3. Rationale for indicator selection

4. Monitoring design and strategy for indicators

5. Analysis and interpretation

6. Reporting scale

7. Data source

8. Links to other indicators

This report has provided some of the background and rationale to inform the development of an invertebrate indicator monitoring plan. The specific details of a monitoring plan would need to be informed by a more detailed analysis of the specific asset and threat area to which the indicator is


31 May 2007 Page 40

designed to measure, existing knowledge, program design and resource availability. The necessary work to develop and trial an invertebrate indicator plan has been identified by the Corangamite CMA as a successor to this report.


31 May 2007 Page 41

5 CONCLUSION Invertebrates provide a rich source of information that can be used to assess the health of an environment. Whether in aquatic or terrestrial systems, invertebrates have been shown to react to certain contaminants, stressors, habitat types or habitat changes. These changes in invertebrate distributions (or numbers) will often happen prior to any measurable chemical or physical property. They are therefore a powerful tool for Governments, regulatory bodies, industries, land owners and land managers to embrace. This has already occurred to a large extent in the aquatic area, where they are routinely used to assess the health of river systems in Australia. In terrestrial environments the uptake has been somewhat slower and is likely driven, to a large extent, by the lack of legislation and regulation compared to the aquatic area. Nevertheless, invertebrates are routinely used in Australia to monitor the rehabilitation of land (mine sites) and researchers are continuing to demonstrate their use as indicators of sustainability in agricultural settings.

Catchment Management Authorities can use targeted invertebrate monitoring as a management tool to assess the health of their Catchments. Currently within Victoria, the health of river systems is assessed under the Victorian River Health Program using the Index of Stream Condition, of which invertebrate monitoring is one component. The river systems are assessed once every five years under this program and provide a course indication to CMAs on the general health of their waterways. This report has identified recent research (Bahrndorff, Ward et al. 2006; Carew, Pettigrove et al. 2003; Carew, Pettigrove et al. 2005) that could be incorporated into this program and would allow the determination of actual pollutants and/or stressors that affect specific regions of CMA waterways. In particular, this method could be developed to monitor salinity and pesticide residues, two important contaminants/stressors of the Corangamite Catchment. This would allow targeted management actions to be implemented by CMAs at specific sites and improve the overall health of their Catchment.

While terrestrial monitoring is less advanced than the aquatic area, there are several areas identified in this report that could be developed into monitoring programs for CMAs. The study initiated by Neville (2003a) and due to be completed in 2007, combined with other monitoring programs already developed (Andersen, Fisher et al. 2004), will provide the data necessary to develop a monitoring program to assess the success of re-vegetation programs within CMAs. This will allow CMAs to develop recommendations on best practice for re-vegetating sites, such as agricultural land, to be made.

This report has identified research which can lead to more environmentally sustainable agricultural practices which can improve the overall health of the terrestrial environment within CMAs. By planting and managing shelterbelts in a particular manner, increases in invertebrate biodiversity can be achieved that will provide better ecosystem functioning and reduced invertebrate pest pressure in adjacent pasture/cropping areas (Gower, Hoffmann et al. 2007; Tsitsilas, Stuckey et al. 2006; Tsitsilas, Umina et al. 2007). This will lead to an increase in farm profitability and a reduction in one of the biggest contaminants found in Victorian Catchments - pesticides. The efficacy of the managed shelterbelts can be assessed through the application of an invertebrate monitoring program. Increases in biodiversity will also be a by-product of the reduction in the input of pesticides into the agricultural landscape. CMAs can use invertebrates to monitor the ‘footprint’ of pesticides in their Catchments (Thomson and Hoffmann 2006) and as a measure of overall health in agricultural areas.

Finally, this report has identified that CMAs could use invertebrates as an indicator of salinity stress in terrestrial environments, which is of utmost importance in Australia and the Corangamite CMA.


31 May 2007 Page 42

Lewis (2003) identified particular groups that show a strong response to increasing salinity gradients in agricultural settings. To develop this further, this study would need to be repeated over a broader area which incorporates a range of salinities on different soil types.


31 May 2007 Page 43

6 REFERENCES Andersen AN, Fisher A, Hoffmann BD, Read JL, Richards R (2004) Use of terrestrial invertebrates for biodiversity monitoring in Australian rangelands, with particular reference to ants. Austral Ecology 29, 87-92. Bahrndorff S, Ward J, Pettigrove V, Hoffmann AA (2006) A microcosm test of adaptation and species specific responses to polluted sediments applicable to indigenous chironomids (Diptera). Environmental Pollution 139, 550-560. Bird PR, Bicknell D, Bulman PA, Burke SJA, Leys JF, Parker JN, van der Somme GI, Voller P (1992) The role of shelter in Australia for protecting soilds, plants and livestock. Agroforestry Systems 20, 59-86. Bonada N, Prat N, Resh VH, Statzner B (2006) Developments in aquatic insect biomonitoring: a comparative analysis of recent approaches. Annual Reviews in Entomology 51, 495-523. Bunn S (1995) Biological monitoring of water quality in Australia: workshop summary and future directions. Australian Journal of Ecology 20, 220-227. Carew ME (2006), An investigation of chironomids (Chironomidae: Diptera) as bioindicators of pollution in urban aquatic environments using DNA-based species identification. PhD thesis. The University of Melbourne. Carew ME, Pettigrove V, Hoffmann AA (2003) Identifying chironomids (Diptera: Chironomidae) for biological monitoring with PCR-RFLP. Bulletin of Entomological Research 93, 483-490. Carew ME, Pettigrove V, Hoffmann AA (2005) The utility of DNA markers in classical taxonomy: using cytochrome oxidase I markers to differentiate Australian Caldopelma (Diptera: Chironomidae) midges. Annals of the Entomological Society of America 98, 587-594. Carmona DM, Landis DA (1999) Influence of refuge habitats and cover crops on seasonal activity-density of ground beetles (Coleoptera: Carabidae) in field crops. Environmental Entomology 28, 1145-1153. Chessman BC (1995) Rapid assessment of rivers using macroinvertebrates: a procedure based on habitat-specific sampling, family level identification and a biotic index. Australian Journal of Ecology 20, 122-129. Chessman BC, McEvoy PK (1998) Towards diagnostic biotic indices for river macroinvertebrates. Hydrobiologia 364, 169-182. CSIRO (1991) 'The insects of Australia: a textbook for students and research workers.' (Melbourne University Press: Carlton)


31 May 2007 Page 44

Dalal RC, Lawrence P, et al. (1999) A framework to monitor sustainability in the grains industry. Australian Journal of Experimental Agriculture 39, 605-620. Davies PE (2000) Development of a national river bioassessment system (AUSRIVAS) in Australia. In 'Assessing the biological quality of fresh waters RIVPACS and other techniques'. (Eds FJ Wright, DW Sutcliffe and MT Furse) pp. 113-124. (Freshwater Biological Association: Ambleside, Cumbria, UK) Dufrene M, Legendre P (1997) Species assemblages and indicator species: the need for a flexible asymmetrical approach. Ecological Monographs 67, 345-366. Gower JMC, Hoffmann AA, Weeks AR (2007) Effectiveness of spring spraying targeting diapause egg production for controlling red legged earth mites and other pests in pasture. Australian Journal of Experimental Agriculture in press. Gurr GM, Wratten SD, Altieri MA (2004) 'Ecological engineering for pest management: advances in habitat manipulation for arthropods.' (CSIRO Publishing: Collingwood) Harvey MS, Yen AL (1989) 'Worms to wasps: an illustrated guide to Australia's terrestrial invertebrates.' (Oxford University Press: South Melbourne) Hellawell JM (1986) 'Biological Indicators of Freshwater Pollution and Environmental Management.' (Elsevier: London) Hodkinson ID, Jackson JK (2005) Terrestrial and aquatic invertebrates as bioindicators for environmental monitoring, with particular reference to mountain ecosystems. Environmental Management 35, 649-666. Jeanneret P, Schupbach B, Luka H (2003) Quantifying the impact of landscape and habitat features on biodiversity in cultivated landscapes. Agriculture Ecosystems and Environment 98, 311-320. Kahn TA (2003) Limnology of four saline lakes in western Victoria, Australia. Limnologica 33, 327-339. Kefford BJ (1996) 'The effect of electrical conductivity on selected macroinvertebrates in four river systems of south western Victoria.' Department of Natural Resources and Environment, Victoria. Kefford BJ (2000) The effect of saline water disposal: implications for monitoring programs and management. Environmental Monitoring and Assessment 63, 313-327. Kefford BJ, Palmer CG, Nugegoda D (2005) Relative salinity tolerance of freshwater macroinvertebrates from the south-east Eastern Cape, South Africa compared with the Barwon Catchment, Victoria, Australia. Marine & Freshwater Research 56, 163-171.


31 May 2007 Page 45

Kefford BJ, Papas PJ, Nugegoda D (2003) Relative salinity tolerance of macroinvertebrates from the Barwon River, Victoria. Marine & Freshwater Research 54, 755-765. Kefford BJ, Paradise T, Papas PJ, Fields E, Nugegoda D (2003) 'Assessment of a system to predict the loss of aquatic biodiversity from changes in salinity.' Land & Water Research & Development Corporation. King JR, Andersen AN, Cutter AD (1998) Ants as bioindicators of habitat disturbance: validation of the functional group model for Australia's humid tropics. Biodiversity and Conservation 7, 1627-1638. Lewandowski I, Hardtlein M, Kaltschmitt M (1999) Sustainable crop production: definition and methodological appraoch for assessing and implementing sustainability. Crop Science 39, 184-193. Lewis N (2003) Can invertebrates be used as indicators of dryland salinity? The identification of candidate assemblages in south-western Victoria. Honours thesis, La Trobe University. Maher WA, Norris RH (1990) Water quality assessment programs in Australia: deciding what to measure, and how and where to use bioindicators. Environmental Monitoring and Assessment 14, 115-130. Majer JD (1978) An improved pitfall trap for sampling ants and other epigaeic invertebrates. Journal of the Australian Entomological Society 17, 261-262. Majer JD (1983) Ants: bio-indicators of minesite rehabilitation, land-use, and land conservation. Environmental Management 7, 375-383. Major RE, Christie FJ, Gowing G, Cassis G, Reid CAM (2003) The effect of habitat configuration on arboreal insects in fragmented woodlands of south-eastern Australia. Biological Conservation 113, 35-48. Marchant R, Hirst A, Norris R, Metzeling L (1999) Classification of macroinvertebrate communities across drainage basins in Victoria, Australia: consequences of sampling on a broad spatial scale for predictive modelling. Freshwater Biology 41, 253-268. Marchant R, Wells F, Newall P (2000) Assessment of an ecoregion approach for classifying macroinvertebrate assemblages from streams in Victoria, Australia. Journal of the North American Benthological Society 19, 497-500. Marino PC, Landis DA (1996) Effect of landscape structure on parasitoid diversity and parasitism in agroecosystems. Ecological Applications 6, 276-284. McGeoch MA (1998) The selection, testing and application of terrestrial insects as bioindicators. Biological Reviews 73, 181-201. Meffe GK, Carroll CR (1994) 'Principles of Conservation Biology.' (Sinauer: Sunderland)


31 May 2007 Page 46

Metzeling L, Perriss S, Robinsom D (2006) Can the detection of salinity and habitat simplification gradients using rapid bioassessment of benthic invertebrates be improved through finer taxonomic resolution or alternative indices? Hydrobiologia 572, 235-252. Neville PJ (2003a) 'Assessing succession and biodiversity of invertebrates within revegetation areas.' La Trobe University, Unpublished. Neville PJ (2003b) 'Assessing the biodiversity value of invertebrates within shelterbelts.' CESAR, La Trobe University. Niemela J, Kotze J, Ashworth A, Brandmayr P, Desender K, New T, Penev L, Samways M, Spence J (2000) The search for common anthropogenic impacts on biodiversity: a global network. Journal of Insect Conservation 4, 3-9. NLWRA (2001) 'Australian dryland salinity assessment 2000: extent, impacts, processes, monitoring and management options.' The National Heritage Trust, Commonwealth of Australia. Norris RH, Hawkins CP (2000) Monitoring river health. Hydrobiologia 435, 5-17. Norris RH, Thoma MC (1999) What is river health? Freshwater Biology 41, 197-209. Nuberg JK (1998) Effect of shelter on temperature crops: a review to define research for Australian conditions. Agroforestry Systems 41, 3-34. Pearson DL (1994) Selecting indicator taxa for the quantitative assessment of biodiversity. Philosophical Transactions of the Royal Society of London Series B 345, 75-79. Perner J, Malt S (2003) Assessment of changing agricultural land use: response of vegetation, ground-dwelling spiders and beetles to the conversion of arable land into grassland. Agriculture Ecosystems and Environment 98, 169-181. Pettigrove V (2006), The impact of contaminated sediments on the indigenous aquatic macroinvertebrates from the Greater Melbourne Area, Australia. PhD thesis, La Trobe University. Pik AJ, Dangerfield JM, Bramble RA, Angus C, Nipperess DA (2002) The use of invertebrates to detect small-scale habitat heterogeneity and its application to restoration practices. Environmental Monitoring and Assessment 75, 179-199. Resh VH, Norris RH, Barbour MT (1995) Design and implementation of rapid assessment approaches for water resource monitoring using benthic macroinvertebrates. Australian Journal of Ecology 20, 108-121. Ridsdill-Smith TJ, Pavri C (2000) Single spring spray protects pastures. Farming Ahead 103, 60-63.


31 May 2007 Page 47

Simpson J, Norris RH (2000) Biological assessment of river quality: development of AUSRIVAS models and outputs. In 'Assessing the biological quality of fresh waters RIVPACS and other techniques'. (Eds FJ Wright, DW Sutcliffe and MT Furse) pp. 125-142. (Freshwater Biological Association: Ambleside, Cumbria, UK) Sinclair C, Hoffmann AA (2003) Developmental stability as a potential tool in the early detection of salinity stress in wheat. International Journal of Plant Sciences 164, 325-331. Thomson LJ, Hoffmann AA (2006) Field validation of laboratory-derived IOBC toxicity ratins for natural enemies in commercial vineyards. Biological Control 39, 507-515. Tsitsilas A, Stuckey S, Hoffmann AA, Weeks AR, Thomson LJ (2006) Shelterbelts in agricultural landscapes suppress invertebrate pests. Australian Journal of Experimental Agriculture 46, 1379-1388. Tsitsilas A, Umina P, Hoffmann AA, Thomson LJ (2007) 'Grass cover characteristics and their effects on beneficial and pest invertebrates in adjacent pasture.' Centre for Environmental Stress and Adaptation Research, The University of Melbourne, unpublished. Umina P, Hoffmann AA (2003) Diapause implications for the control of Penthaleus species and Halotydeus destructor (Acari: Penthaleidae) in south eastern Australia. Experimental and Applied Acarology 31, 209-223. Weeks AR, Hoffmann AA (2000) Competitive interactions between two pest species of earth mites, Halotydeus destructor and Penthaleus major (Acarina: Penthaleidae). Journal of Economic Entomology 93, 1183-1191. Williams WD, Boulton AJ, Taafe RG (1990) Salinity as a determinant of salt lake fauna: a question of scale. Hydrobiologia 197, 257-266. Wright JD, Armitage PD, Furse MT (1989) Prediction of invertebrate communities using stream measurements. Regulated Rivers 4, 147-155.


31 May 2007 Appendix 1: Page A1

Appendix 1 - Site map and table outlining the composition of shelterbelts within the Gerangamete Agroforestry for Salinity Control Trial


A map of the Agroforestry for Salinity Control Trial sites from Neville (2003b) showing the location of shelterbelts. Shelterbelts are numbered 1-24, the Eucalypt paddock 25, Casuarina paddock 26 and the remnant forest 27.

Classification of shelterbelt types (based on species composition and number of rows) within the Agroforestry for Salinity Control Trial sites from Neville (2003b). Eleven shelterbelt types were identified. Shelterbelt Type

Rows Shelterbelt Composition Ratio of rows

1 1 Cypress - 2 2 Eucalyptus - 3 3 Eucalyptus - 4 5 Eucalyptus - 5 5 Eucalyptus and Acacia 4: 1 6 5 Eucalyptus and Acacia (3: 2) 3: 2 7 5 Eucalyptus, Acacia and Leptospermum 1: 3: 1 8 5 Eucalyptus, Acacia and Casuarina 3: 1: 1 9 5 Eucalyptus, Melaleuca and Casuarina 3: 1: 1 10 5 Melaleuca, Acacia, Casuarina 2: 2: 1 11 10 Eucalyptus and Casuarina 6: 4




Appendix 2 - Recent terrestrial invertebrate monitoring examples and the factors they were trying to evaluate (taken from Hodkinson and Jackson 2005).



Indicator Type Invertebrate group Habitat General (habitat continuity) Fungivorous beetles General (quality) Spiders Diptera Coccinellid beetles Syrphid flies Staphylinid beetles Cryptostigmatic mites Rare beetles Tiger beetles Butterflies Landscape and habitat features Lepidoptera, spiders, beetles Agroecosytems Heteropterous bugs Ants General invertebrates Savanna grassland Dung beetles Grassland Collembola Forest Fungivorous insects Borreal forest Coleoptera Rangeland Ants Chemical/Pollutant pH/acidification Soil microarthropods Heavy/trace metals Several soil invertebrates Sarcophagid flies Air pollution/acid deposition Several invertebrates Spiders Collembola Cryptostigmatic mites Day flying Lepidoptera Nitrogen inputs Collembola Pesticides Collembola Soil microarthropods Various soil invertebrates Asbestos Sarcophagid flies Habitat Change Grassland topsoil removal Carabid beetles Land management practice Ants Dispersing insects Extent of logging Spiders Dung beetles Mining disturbance in savanna Grasshoppers General ecosystem health Many invertebrates Landscape/ecosystem

sustainability Many invertebrates

Soil invertebrates Earthworms Impact of GM crops Invertebrates Soil management Soil invertebrates Change in general habitat quality Bees and wasps Forest restoration General invertebrate



Indicator Type Invertebrate group community

Farming impacts Protozoa Forest degradation Tiger Beetles Various insects and nematodes Sheep grazing Several insect groups Grassland management Coleoptera and Orthoptera Pollutant effects on forest Scolytid beetles Forest disturbance Butterflies Moths Forest management Mycetophilid flies Forest floor invertebrates Longicorn beetles Grassland habitat disturbance Hempitera Urbanization Carabid beetles Habitat fragmentation Ants, Coleoptera, Arenaea,

Diptera, Hymenoptera



Appendix 3 - A summary of the sensitivity of common taxa present in microcosm experiments to sediment pollution in aquatic environments in the greater Melbourne area (taken from Pettigrove 2006).



Taxon Sensitivity to sediment pollution Tanytarsus fuscithorax Opportunistic to low-level pollution, sensitive to petroleum hydrocarbons,

nutrients, lead and zinc Micronecta annae Possibly sensitive to moderately polluted sediments Polypedilum watsoni Sensitive to petroleum hydrocarbons and tolerant to heavy metals Polypedilum leei Opportunistic and tolerant to copper polluted sediments Polypedilum vespertinus Sensitive to petroleum hydrocarbons and heavy metals Cricotopus albitarsis Opportunistic, tolerant of heavy metals and moderately sensitive to

petroleum hydrocarbons Cladotanytarsus bispinosus Moderately tolerant of petroleum hydrocarbons and sensitive to heavy

metals Chironomous februarius Opportunistic in nutrient enriched sediments and moderately sensitive to

toxicants Parachironomous sp. M1 Appears tolerant to sediment pollution Ceratopogonidae Tolerant to sediment pollution Mesovelia sp. Sensitive to sediment pollution Kiefferulus martini Sensitive to sediment pollution, possibly due to petroleum hydrocarbons Cladopelma curtivalva Moderately sensitive to petroleum hydrocarbons and heavy metal pollution Necterosoma pencillatum Tolerant to sediment pollution Larsia albiceps Sensitive to sediment pollution, possibly due to petroleum hydrocarbons

and lead/zinc Riethia strictoptera Very sensitive to sediment pollution Tasmanocoenis sp. Moderately tolerant to petroleum hydrocarbons, but sensitive to heavy

metals Procladius sp. Stressed by sediment pollution, potential bioindicator of sublethal stress Paratanytarsus grimmii Moderately tolerant to sediment pollution, adults are very sensitive to

pollutants Psychodidae Strong preference for nutrient enriched sediments Aedes sp. May prefer nutrient enriched sediments, may be sensitive to elevated

copper pollution Muscidae Strong preference for nutrient enriched sediments Kiefferulus intertinctus Sensitive to sediment pollution, may be most sensitive to heavy metals

and nutrients Eretes australis Tolerant to sediment pollution Corynoneura australiensis Tolerant to sediment pollution Dicrotendipes conjunctus Appears to be tolerant to sediment pollution Anisops sp. Tolerant to sediment pollution Oecetis sp. Sensitive to sediment pollution, but tolerant to heavy metals and nutrients

INVERTEBRATE MONITORING FOR ASSESSING ECOSYSTEM …

Documents