ECOSYSTEM CHANGE IN ANTARCTICA
Environmental changes within the Western Antarctic Peninsula (WAP) ecosystems are some of the greatest occurring on the planet.
Biological responses to these changes within the WAP should also be evident in the top predators, where trophic effects are integrated and/or amplified. We are following trophic changes at the top of the food web, in the top predators, back over the past 140 years.
The increases in mean winter air temperature and associated decreases in winter sea-ice cover make it comparable to the most rapidly warming regions of the Arctic. During the past 30 years, the northern WAP ecosystem has shown a suite of sustained biological changes at many levels within the ecosystem: decreases in primary productivity and changes in phytoplankton community structure; change in the structure of grazer communities and in krill and salp abundance; and the disappearance of krill-feeding specialist penguins.
This major change in the Antarctic food web offers an invaluable observatory of climate change and marine ecosystem response, which can be applied to studying disrupted ecosystems globally.
Drawings by Alicia Guerrero and Tracey Rogers