Satellite telemetry and seasonal movements of Magpie Geese (Anseranas semipalmata) in tropical northern Australia

Abstract

Knowledge of the patterns of movement of tropical waterfowl should assist in long-term conservation of these birds and their wetlands. Data that indicate or suggest the extent of connectivity between populations help us to make decisions, particularly when those populations are threatened by loss and fragmentation of habitat. To date, there has been little research on tropical waterfowl, with most work on this group of birds done in temperate regions. We tracked the seasonal movements of 10 Magpie Geese (Anseranas semipalmata) in tropical northern Australia, predominantly within Kakadu National Park, using satellite telemetry. Movements were multi-directional and the maximum linear distance travelled by an individual was 114 km from the site of release, over 38 weeks of tracking. Movements did appear to be related to seasonal environmental fluctuations, with some birds moving to favoured breeding and foraging sites, but most monitored birds were resident within the national park. No accurate data were obtained beyond 12 months, with most birds apparently losing their telemeters within 6 months. Just 62% of point-location data were accurate to within 1000 m. Our work provides further ecological data on a species threatened by sea-level rise and important to Aboriginal and recreational hunters.