Activity budgets and habitat use of the Green Pygmy-goose (Nettapus pulchellus) on dry-season refuges in Kakadu National Park, Northern Territory
Errol R. Nye A B C and Chris R. Dickman AA Institute of Wildlife Research, School of Biological Sciences, A08, The University of Sydney, NSW 2006, Australia.
B Present address: School of Science and Technology, Charles Sturt University, LMB 588, Wagga Wagga, NSW 2678, Australia.
C Corresponding author. Email: enye@csu.edu.au
Emu 105(3) 217-222 https://doi.org/10.1071/MU05027
Submitted: 26 May 2005 Accepted: 15 August 2005 Published: 12 October 2005
Abstract
We studied behavioural activity budgets and habitat use of Green Pygmy-geese (Nettapus pulchellus) in Kakadu National Park during the dry season in 2000, in order to assess the resource requirements and conservation needs of the species. Observations were made in three wetlands, using focal-interval sampling on an instantaneous basis. No differences were found in behaviour or habitat use between the sexes among the three wetland sites. Green Pygmy-geese were largely restricted to floating vegetation. Individuals spent most of each day feeding, with shorter periods spent preening or swimming. During the dry season, wetlands contract to some 5% of the area covered during the wet, probably increasing competition among the birds for food and habitat and leaving them vulnerable to threatening processes such as wetland draining. We suggest that a program of survey and monitoring be implemented at selected sites, and that the impacts of introduced herbivores be assessed and appropriately managed.
Acknowledgments
We thank Richard Kingsford for helpful comments; Bobby Tamayo, Reuben Schmitt, Roger Nye and Earthwatch volunteers for assistance with fieldwork; and the Environmental Research Institute of the Supervising Scientist for provision of accommodation and assistance during the study. Terry Bailey from Parks Australia North provided valuable support while working in Kakadu National Park. The project was funded by Earthwatch and an ARC SPIRT Grant to Eric J. Dorfman.
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