On April 21 the Nathaniel B. Palmer will leave Punta Arenas, Chile, for Antarctic waters, carrying 37 scientists to one of the most remote areas on Earth: the waters surrounding Antarctica, sometimes called the Southern Ocean. There, as part of the National Science Foundation–funded Southern Ocean Global Ocean Ecosystems Dynamics (SOGLOBEC) project, biologists from Woods Hole Oceanographic Institution and other organizations will study the winter behavior and distribution of krill, a keystone species in the Antarctic ecosystem. They’re studying what happens to krill over the winter, when the crustaceans are dependent on the algae that grow under sea ice, which appears to be shrinking. They are also studying water currents and other environmental factors. Another concern is overfishing. A few nations harvest the crustaceans now for use as fish food, bait, and human consumption, and the potential for mass harvesting worries many biologists. As a keystone species in the ecosystem, nearly every animal in the Antarctic—whales, penguins, fish, and more—depends on krill for survival. “If something happens to the krill ...” says SOGLOBEC chairperson Eileen Hofmann, “the whole food web can collapse.”