Project Leader: Dr Alan Andersen, CSIRO Division of Wildlife & Ecology, Darwin

Project 3.2.1

Summary | Aims | Application of research Research Progress |  Future Directions | Publications |  Project Team |

Illustration from Alan Andersen's recent book which is the first to describe the ants of northern Australia at the species level—see links below. Illustrations: Peter Jacklyn

Summary

This project wasprimarily concerned with defining and assessing ecosystem health, and providing ecological indicators for ecosystem management. Insects and other invertebrates (spiders, beetles, grasshoppers and termites) play key roles in ecosystem health because they contribute most of the faunal biomass and biodiversity in ecosystems, and regulate most of the ecological processes that drive ecosystem health. Their high diversity, biomass, functional importance, sensitivity to environmental change, and ease of sampling, make them effective bio-indicators of ecosystem health. If assemblages of invertebrates are in good shape, then this indicates that the ecosystem more generally is likewise in good shape.

Aims

1. To document the distribution of savanna invertebrate assemblages;
2. To describe their responses to land-use;
3. To examine their reliability as bioindicators;
4. To develop protocols for their efficient use as bio-indicators.

Attention throughout the world has focused on the use of invertebrates as bio-indicators in ecosystem management, because invertebrates contribute most to global biodiversity as well as drive many of the key processes maintaining ecosystem function. Invertebrates have a long history of use as bio-indicators in aquatic systems, and for two decades ants have been extensively used by the Australian mining industry as indicators of restoration success.

The project is closely associated with other with data on soils and vegetation, invertebrates and vertebrates collected at the same sites. Taken together, these taxa represent a considerable proportion of total biodiversity.

Application of research

In collaboration with project staff, invertebrates were used by land managers in the following contexts:

• Conservation planning (range of Parks & Wildlife Commission of the NT projects)
• Biodiversity impacts of woody weeds (NSW National Parks & Wildlife Service)
• Ecological responses to Great Artesian Bore Recapping Program (Qld Dept. Natural Resources & Mines)
• Mine-site restoration (German Creek and Callide consultancies)
• Ants were included in draft strategy for biodiversity monitoring in rangelands, as part of the National Land and Water Audit
• Within the TS-CRC, the project contributes to the VRD Management Study by documenting the impact of the dominant land uses (grazing and fire) on biodiversity, and by comparing the various indicators of ecological condition.

Progress

• · VRD grazient gradient study completed, paper on ant responses published, and draft paper on spider responses almost completed.
• Invertebrate contributions to PWCNT Tiwi Islands (ants) and Darwin region fragmentation (grasshoppers) studies completed.
• Analysis of effectiveness of simplified ant sampling protocol completed, and paper submitted for publication.
• Consultancies at German Creek and Callide mines completed.
• Simplified ant sampling protocol (requiring 10 per cent of effort) shown to be reliable.
• New ant genus for the NT (Anonychomyrma) found on Melville Island, and first Australian record of possibly a New Guinean group within the ant genus Rhytidoponera found in central Arnhem Land.
• NTU/CRC student Ben Hoffmann's PhD thesis on the responses of ant communities to disturbance completed and conferred.
• Ants of Northern Australia published
• Papers published on grasshoppers as indicators of disturbance in the Kakadu region, and responses of beetles to fire at Kapalga

Future directions

• Relationship between invertebrate assemblages and other measures of ecosystem health
• Role of soil macro-invertebrates (especially termites and ants) in water, carbon and nutrient dynamics

Publications

2001

Andersen, A.N. & Müller, W.J. (2000) Arthropod responses to experimental fire regimes in an Australian tropical savannah: ordinal-level analysis. Australian Journal of Ecology, 25, 199-209.

Andersen, A.N. & Majer, J.D. (2000) The Australian rain forest ant fauna: a biogeographic overview. In: (eds. D. Agosti, J.D. Majer & L. Alonso & T. Schultz) Sampling Ground-dwelling Ants: Case Studies From the World's Rainforests, pp. 51-58. Curtin University of Technology School of Environmental Biology Bulletin No. 18, Perth, Australia.

Hoffmann, B.D., Griffiths, A.D. & Andersen, A.N. (2000) Response of ant communities to dry sulphur deposition from mining emissions in semi-arid northern Australia, with implications for the use of functional groups. Austral Ecology 25, 653-663.

Andersen, A.N. (2000) A global ecology of rain forest ants: functional groups in relation to stress and disturbance. In: (eds. D. Agosti, J.D. Majer, L. Alonso & T. Shultz) Ants: Standard Methods for Measuring and Monitoring Biodiversity. Smithsonian Institution Press, Washington D.C., USA.

Read, J.L. & Andersen, A.N. (2000) The value of ants as early warning bioindicators: responses to pulsed cattle grazing at an Australian arid zone locality. Journal of Arid Environments 45, 231-251.

Andersen, A.N., Azcárate, F.M. & Cowie, I.D. (2000) Seed selection by an exceptionally rich community of harvester ants in the Australian seasonal tropics. Journal of Animal Ecology 69, 975-984.

Andersen, A.N. (2000) The Ants of Northern Australia: A Guide to the Monsoonal Fauna. CSIRO Publishing, Melbourne.

Andersen, A.N., Lowe, L.M. and Rentz, D.C.F. (2000) The grasshopper (Orthoptera: Acridoidea, Eumastacoidea and Tettigonioidea) fauna of Kakadu National Park in the Australian seasonal tropics: biogeography, habitat associations and functional groups. Australian Journal of Zoology 48, 431-442.

Orgeas, J. & Andersen, A.N. (2001) Fire and biodiversity: responses of grass-layer beetles to experimental fire regimes in an Australian tropical savanna. Journal of Applied Ecology 38, 49-62.

Blanche, K.R., Andersen, A.N. & Ludwig, J.A. (2001) Rainfall-contingent detection of fire impacts: responses of beetles to experimental fire regimes in a tropical savanna. Ecological Applications 11, 86-96.

Andersen, A.N., Ludwig, J.A., Lowe, L.M. and Rentz, D.C.F. (2001) Grasshoppers as bioindicators: responses to ecological disturbance in the Australian seasonal tropics. Austral Ecology 26, 213-222.

Woinarski, J.C.Z., Andersen, A.N., Churchill, T.B. and Ash, A. (in press) Response of ant and terrestrial spider assemblages to pastoral and military land use, and to landscape position, in a tropical savanna woodland in northern Australia. Ecological Management & Restoration.

Andersen, A.N., Hoffmann B.D., Müller, W.J. & Griffiths, A.D. (submitted) Using ants as bioindicators in land management: simplifying assessment of ant community responses. (Journal of Applied Ecology).

Consultancy reports

Andersen, A.N. (2001) Ant monitoring at Callide Mine, central Queensland: Elsol study, April 2001. Report to Callide Mine. Andersen, A.N. & Hoffmann, B. (2001) Ant monitoring at Callide Mine, central Queensland: 2001 sampling. Report to Callide Mine.

2000

Andersen, A.N. & Müller, W.J. (in press) 'Arthropod responses to experimental fire regimes in an Australian tropical savanna: 'ordinal'-level responses', Australian Journal of Ecology.

Andersen, A.N. (2000) 'A global ecology of rain forest ants: functional groups in relation to stress and disturbance, in Measuring and Monitoring Ant Biodiversity, Agosti, D., Majer, J.D., & Tennant, L. (eds) Smithsonian Institution Press, Washington, US.

Andersen, A.N. & Hoffmann, B. (2000) 'Ant monitoring at Callide Creek Mine, Queensland,' Report to Land Reclamation Services Pty. Ltd.

Andersen, A.N. & Hoffmann, B. (2000) 'Ant monitoring at German Creek Mine, Queensland: 2000 sampling', Report to Capricorn Coal Management Pty. Ltd.

Blanche, K.R., Andersen, A.N. & Ludwig, J.A. (in press) 'Rainfall-contingent detection of fire impacts: responses of beetles to experimental fire regimes in a tropical savanna', Ecological Applications.

Churchill, T.B. and Arthur, J.M. (1999) Measuring spider richness: effects of different sampling methods and spatial and temporal scales', Journal of Insect Conservation, vol. 3, pp. 287-295.

Hoffmann, B.D., Andersen, A.N. & Hill, G.J.E. (1999) 'Impact of an introduced ant on native rain forest invertebrates: Pheidole megacephala in monsoonal Australia', Oecologia, vol. 120, pp. 595-604.

Hoffmann, B.D., Griffiths, A.D. & Andersen, A.N. (in press) 'Response of ant communities to dry sulphur deposition from mining emissions in semi-arid northern Australia, with implications for the use of functional groups', Australian Journal of Ecology.

Hoffmann, B. D. (in press) 'Changes in ants species composition and community organisation along grazing gradients in semi-arid rangelands of the Northern Territory', The Rangeland Journal.

Project team

Dr Alan Andersen (CSIRO Sustainable Ecosystems)
Dr Tracey Churchill (CSE, TS-CRC funded)
Mr Tony Hertog (CSE)
Ms Lyn Lowe (CSE)
Mr Gus Wanganeen (CSE)
Ms Hazel Brown (CSE)
Mr Andy Chapman (CSE)
Mr Ben Hoffmann (CSE)
Ms Kathryn Schneider (University of S.A. Masters student)