LSU Co-Leads Study Investigating Human Interference in Antarctic Ecosystems

Dr. Michael Polito, assistant professor in Louisiana State University’s Department of Oceanography & Costal Sciences, co-lead an investigation with researchers from University of Rhode Island, University of Oxford, University of California-Santa Cruz, and the University of Saskatchewan. The researchers endeavored to better understand how human interference in Antarctic ecosystems affected Antarctic krill, a key food source of penguins.

Although remote, Antarctica has a long history of human impacts on its ecosystems and animals. By the early to mid-1900s, humans had hunted many of its seals and whales nearly to extinction. Seal and whale populations are now recovering, but decades of climate change and a growing commercial fishing industry have further degraded the environment.

Researchers studied chinstrap penguins because of their severe population declines and gentoo penguins because of their population increases over the past century. They found that both types of penguins primarily ate krill in the first half of the century when there was a surplus. When the surplus ended, gentoo penguins adapted their diets to include fish and squid, while the chinstrap penguins continued to feed almost exclusively on krill.

"Our results indicate that historic harvesting and recent climate change have altered the Antarctic marine food web over the past century. Moreover, the differing diet and population responses we observed in penguins indicate that species such as chinstrap penguins, with specialized diets and a strong reliance on krill, will likely continue to do poorly as climate change and other human impacts intensify."

The study was funded by NSF Office of Polar Programs and the Antarctic Science Bursary. Findings are published in the Proceedings of the National Academy of Sciences.

Read the full story from ScienceDaily here.