Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Predation of artificial ground nests in Australian tropical savannas: inverse edge effects

Fiona J. Fraser A C and Peter J. Whitehead B
+ Author Affiliations
- Author Affiliations

A Tropical Savannas Cooperative Research Centre and Parks and Wildlife Commission of the Northern Territory, Darwin, NT 0900, Australia; and Centre for Resources and Environmental Studies, Australian National University, Canberra, ACT 0200, Australia. Present address: Caring for Country Unit, Northern Land Council, PO Box 42921, Casuarina, NT 0811, Australia.

B Key Centre for Tropical Wildlife Management, Northern Territory University, Darwin, NT 0909, Australia.

C Corresponding author.

Wildlife Research 32(4) 313-319 https://doi.org/10.1071/WR04021
Submitted: 22 March 2004  Accepted: 19 April 2005   Published: 5 July 2005

Abstract

Depredation of artificial ground nests was examined in tropical savanna in northern Australia to assess potential predation pressures on nests of the partridge pigeon (Geophaps smithii), a declining tropical granivore. Predation rates were examined at two sites, Kakadu National Park (which supported a relatively high density of partridge pigeons) and Berry Springs (which had greater habitat fragmentation and comparatively low partridge pigeon density). The effects of distance from road, understorey structure, topography and nest-microsite concealment on nest predation rates were examined. Artificial-nest predation rates were greater at 150 m from roads than <1 m from the roadside. Predation rates did not vary with understorey structure, topography, or level of nest concealment. There was marked variation between sites, with predation levels at Kakadu more than double those recorded for Berry Springs. Discerning predator identity, or even the size of a predator, from marks left in clay eggs proved difficult and was possible for ~35% of predation events. Of these, 42% of predation events involved predators of a size we considered too small to take a natural partridge pigeon nest. We suggest that extrapolation from artificial to natural ground-nest predation rates be undertaken with caution for landscapes such as Australia’s tropical savanna, which supports a high diversity and abundance of small potential predators of artificial nests. There was no evidence of predation by birds, and the methodology proved inadequate for identifying predation by feral cats (Felis catus).


Acknowledgments

The research was carried out as part of a Ph.D. degree at the Australian National University and financial support was provided by the Tropical Savannas Cooperative Research Centre and the Parks and Wildlife Commission of the Northern Territory. Traditional Owners within Kakadu National Park and Parks Australia gave permission for research to be conducted within the park. The Northern Territory Museum allowed access to their mammal collection. We thank the Jim Jim District ranger staff for their cooperation and E. Astondae and M. A. Reid for assistance in the field. We are grateful to K. McGuinness and B. Brooke for statistical advice and D. C. Franklin, R. A. Noske, J. C. Z. Woinarski, P. A. S. Wurm and two anonymous referees for comments on drafts of this paper.


References

Batary, P. , and Baldi, A. (2004). Evidence of an edge effect on avian nest success. Conservation Biology 18, 389–400.
Crossref | GoogleScholarGoogle Scholar | Blakers M., Davies S. J. J. F., and Reilly P. N. (1984). ‘The Atlas of Australian Birds.’ (Melbourne University Press: Melbourne.)

Braithwaite, R. W. , and Werner, P. A. (1987). The biological value of Kakadu National Park. Search 16, 296–301.
Brouwer J., and Garnett S. (1990). Threatened birds of Australia: an annotated list. RAOU Report No. 68. Birds Australia, Melbourne.

Burkey, T. V. (1993). Edge effects in seed and egg predation at two neotropical rainforest sites. Biological Conservation 66, 139–143.
Crossref | GoogleScholarGoogle Scholar | Cogger H. G., and Heatwole H. (1981). The Australian reptiles: origins, biogeography, distribution patterns and island evolution. In ‘Ecological Biogeography of Australia’. (Ed. A. Keast.) pp. 1331–1374. (Junk: The Hague, The Netherlands.)

Donovan, T. M. , Jones, P. W. , Annand, E. M. , and Thompson, F. R. (1997). Variation in local-scale edge effects: mechanisms and landscape context. Ecology 78, 2064–2075.
Franklin D. C. (1999b). Patterns of decline of granivorous birds in the northern Australian savannas. M.Sc. Thesis, Northern Territory University, Darwin.

Fraser F. J. (2000). The impacts of fire and grazing on the partridge pigeon: the ecological requirements of a declining tropical granivore. Ph.D. Thesis, Australian National University, Canberra.

Frith H. J. (1982). ‘Pigeons and Doves of Australia.’ (Rigby: Adelaide.)

Gardner, J. L. (1998). Experimental evidence for edge-related predation in a fragmented agricultural landscape. Australian Journal of Ecology 23, 311–321.
Garnett S. (1992). ‘Threatened and Extinct Birds of Australia.’ (Royal Australian Ornithologists Union: Melbourne.)

Goosem, M. (2000). Effects of tropical rainforest roads on small mammals: edge changes in community composition. Wildlife Research 27, 151–163.
Crossref | GoogleScholarGoogle Scholar | Higgins P. J., and Davies S. J. J. F. (Eds) (1996). ‘Handbook of Australian, New Zealand and Antarctic Birds. Volume 3. Snipe to Pigeons.’ (Oxford University Press: Melbourne.)

Kakadu Board of Management (1999). Kakadu National Park Plan of Management. Kakadu Board of Management and Parks Australia, Jabiru.

Keyser, A. J. , Hill, G. E. , and Soehren, E. C. (1998). Effects of forest fragment size, nest density, and proximity to edge on risk of predation to ground-nesting passerine birds. Conservation Biology 12, 986–994.
Crossref | GoogleScholarGoogle Scholar | Lee A. K., Baverstock P. R., and Watts C. H. S. (1981). Rodents: the late invaders. In ‘Ecological Biogeography of Australia’. (Ed. A. Keast.) pp. 1525–1548. (Junk: The Hague, The Netherlands.)

Leimgruber, P. , McShea, W. J. , and Rappole, J. H. (1994). Predation on artificial nests in large forest blocks. Journal of Wildlife Management 58, 254–260.
Payne C. D. (1997). ‘The GLIM system 3.77.’ (NAG, Oxford and Royal Statistical Society: London.)

Pianka E. R., and Schall J. J. (1981). Species densities of Australian vertebrates. In ‘Ecological Biogeography of Australia’. (Ed. A. Keast.) pp. 1675–1694. (Junk: The Hague, The Netherlands.)

Picman, J. (1988). Experimental study of predation on eggs of ground-nesting brids: effects of habitat and nest distribution. Condor 90, 124–131.
Press A. J., Brock J., and Andersen A. N. (1995). Fauna. In ‘Kakadu: Natural and Cultural Heritage and Management’. (Eds A. J. Press, D. A. M. Lea, A. Webb and A. Graham.) pp. 318. (Australian Nature Conservation Agency, North Australia Research Unit Australian National University: Darwin.)

Ricklefs, R. E. (1980). Geographical variations in clutch size among passerine birds: Ashmole’s hypothesis. Auk 97, 38–49.
Stocker G. C., Mott J. J., Gill A. M., Groves R. H., and Noble I. R. (1981). Fire in tropical forests and woodlands of northern Australia. In ‘Fire and the Australian biota’. (Eds A. M. Gill, R. H. Groves and I. R. Noble.) pp. 425–439. (Australian Academy of Science: Canberra.)

Strahan R. (1998). ‘The Mammals of Australia: the National Photographic Index of Australian Wildlife.’ (Reed New Holland: Sydney.)

Taylor, L. N. H. , and Ford, H. A. (1998). Predation of artificial nests in a fragmented landscape on the New England tablelands of New South Wales. Wildlife Research 25, 587–594.
Crossref | GoogleScholarGoogle Scholar | Woinarski J. C. Z., and Dawson F. (2002). Limitless lands and limited knowledge: coping with uncertainty and ignorance in northern Australia. In ‘Ecology, Uncertainty and Policy: Managing Ecosystems for Sustainability’. (Eds J. W. Handmer, T. W. Norton and S. R. Dovers.) pp. 83–115. (Pearson Education Limited: Kuala Lumpur.)

Yahner, R. H. , and Mahan, C. G. (1997). Effects of logging roads on depredation of artificial ground nests in a forested landscape. Wildlife Society Bulletin 25, 158–162.


Yahner, R. H. , and Wright, A. L. (1985). Depredation on artificial ground nests: effects of edge and plot age. Journal of Wildlife Management 49, 508–513.