Predicted habitat and area of ecological significance changes for top predators in the Prydz Bay, East Antarctica, under future climate changes

Abstract

Prydz Bay, one of the most crucial primary production sites in East Antarctica, provides habitats for numerous top predators. Seabirds and marine mammals are regarded as vital indicators of marine resource conditions due to their high sensitivity to climate change. However, research on the habitats and Areas of Ecological Significance (AES) for top predators in this region is significantly lacking, yet identifying these areas is crucial for addressing the impacts of future climate changes. This study utilized field survey data from 15 top predators in Prydz Bay, combined with MaxEnt and Zonation models, to predict and identify their suitable distribution areas and AES. Furthermore, it integrated CMIP6 Earth system model data to forecast potential changes in these habitats and AES under various future scenarios. The results indicate that the top predator community in Prydz Bay includes 10 marine mammals and 25 birds. Key environmental variables affecting the distribution of these predators include sea ice concentration (SIC), mixed layer thickness (Mlotst), and sea surface temperature (SST). The total habitat area for the Southern Fulmar (Fulmarus glacialoides) and the area of highly suitable habitat for the Light-mantled Sooty Albatross (Phoebetria palpebrata) are projected to continue decreasing. Three AES were identified in the coastal and central to eastern pelagic regions of Prydz Bay. The areas of AES in the coastal region are expected to decrease, while AES in the pelagic regions are anticipated to shift eastward in the future. This study provides critical insights for prioritizing conservation efforts in the rapidly changing Antarctic ecosystem, offering a robust framework for adaptive habitat management.