Simulating changes in polar bear subpopulation growth rate due to legacy persistent organic pollutants – Temporal and spatial trends

Although atmospheric concentrations of many conventional persistent organic pollutants (POPs) have decreased in the Arctic over past few decades, levels most POPs and mercury remain high since 1990s or start to increase again areas, especially polar bears. So far, studies generally focused on individual effects POPs, do not directly link POP prey species population-specific parameters. In this study we therefore aimed estimate effect legacy population growth rate nineteen bear subpopulations. We modelled development three scenarios, based sensitivity distributions (SSDs) derived for ecotoxicity data endothermic species. first scenario, bears were HC50 (the concentration at which 50% is affected). The other two scenarios HC5 HC95. Considerable variation could be observed among scenarios. our intermediate predicted subpopulation decline ten out 15 estimated was least reduced Gulf Boothia Foxe Basin. On average, PCB (in ?g/g toxic equivalency (TEQ)) posed largest threat subpopulations, with negative rates majority did find a correlation between changes monitored trends chemical-subpopulation combinations. Modelled increased time, implying decreasing PCBs, DDTs, mercury. Polar subpopulations are reportedly still declining four seven sufficient long-term monitoring available, as reported by IUCN-PBSG. This implies that emerging anthropogenic stressors may affect