New paper models fishing and climate effects on krill and their predators in the Antarctic

Overfishing and climate change are co-occurring threats to marine ecosystems and the ways in which they benefit society. Farallon Institute’s Dr. Emily Klein, in collaboration with the NOAA Southwest Fisheries Science Center Antarctic Ecosystem Research Division (Jefferson Hinke and George Watters) and British Antarctic Survey (Tony Phillips and Simeon Hill) used a mathematical model to test outcomes of climate change to managing a large (~200,000 metric ton) international krill fishery. In their study area of the Antarctic Peninsula, this fishery targets Antarctic krill (Euphausia superba), which are also critical forage for an array of charismatic predators important for ecotourism and of conservation concern, including penguins, seals, and whales. The scientists found warming waters associated with climate change could reduce individual krill weight by 40%, significantly reducing the amount of krill available for predators and the fishery, with concurrent reductions in predator abundances by the end of the 21st century. Fishing at currently permitted levels exacerbated these risks, with projected declines in penguin abundance of over 30% by century’s end. Fishing moratoriums were found to alleviate collective risks, in some cases by 20-30% for certain penguin populations. Importantly, these results depend on location and predator group, suggesting the importance of protective measures for specific populations of wildlife. In particular, the authors argue management may be able to reduce risks by implementing marine protected areas and management strategies that use monitoring to update when and how fishing occurs in response to changes in predator populations.

Read more about this study published in this weeks issue of PLoS One here.