Space use by waterfowl reveals scale mismatches in contemporary environmental management, including mitigation of human-wildlife conflict

Abstract Context Conservation requires aligning the spatial, temporal, and functional scales of environmental management with those of interlinked ecological processes. Objectives To assist Indigenous Ngāi Tahu and government-mandated authorities in the management of black swans ( kakī anau , Cygnus atratus) in the South Island of Aotearoa New Zealand, we investigated the effects of land cover on space use by swans and identified scale mismatches in contemporary gamebird and wetland management. Methods We GPS-tracked 48 swans over one year and compared home range sizes with spatial scales of gamebird management. We also examined relative preferences of swans for different land-cover types to understand the potential for human-wildlife conflict, an influential component of gamebird and wetland management. Results Home ranges were typically located within a single waterbody or catchment, whereas gamebird management units each comprised numerous catchments. Within home ranges, swan location records coincided with aquatic vegetation, sandy shorelines, and flooded deciduous hardwoods. Contrary to common perceptions among farmers (primarily European New Zealanders) of swans as widespread pests, swans significantly avoided pasture, except near some shorelines and nesting colonies where wetlands have been converted to pasture. Conclusions Regional-scale waterfowl management that does not account for habitat selection within home ranges (a spatial scale mismatch) could obscure patterns and determinants of population changes. Moreover, management geared towards suppressing waterfowl numbers in the interests of agricultural land uses that have encroached upon wetlands (a functional scale mismatch) could further degrade waterfowl populations. Mitigating these scale mismatches requires equitable governance arrangements that recognize Indigenous Peoples’ rights and values associated with the environment.