Broad-scale opportunistic movements in the tropical waterbird Anseranas semipalmata: Implications for human-wildlife conflicts

Waterbirds commonly undertake extensive movements in search of resources. While much is known about waterbird movements within temperate regions where resource distribution is seasonally predictable, less is understood about waterbird movements in tropical and subtropical environments where the temporal distribution of resource is less predictable. This knowledge is critical to understanding a species’ response to environmental and anthropogenic changes to natural habitats. Here, we investigated the movement behaviour of a tropical waterbird of northern Australia, the Magpie Goose (Anseranas semipalmata), seasonally utilising a recently developed mixed natural-anthropogenic landscape. Using satellite telemetry, we assessed the daily movements and space use of 18 individuals (4673 goose-days) to determine whether these individuals spent the year locally, migrated seasonally from further areas, or were transitory individuals from across northern Australia. Geese released from peri-urban and rural areas in the late dry season dispersed to both local (≤ 50 km) and distant (≤ 566 km) floodplain systems over the wet season. Tracked individuals returned to sites within the same floodplain systems in the wet season and within the same anthropogenic areas in the late dry season over consecutive years. Our results suggest that anthropogenic environments may provide predictable resources for Magpie Geese during a seasonal bottleneck of natural resources. We highlight the need to learn more about waterbird movement behaviour within tropical human-dominated landscapes to evaluate the likelihood that predictable resources could exacerbate human–wildlife conflicts, and the possible long-term effects on species population dynamics, behaviour and distribution.