Climate and sea changes in the Southern Ocean create conditions that favor the growth of salps over krill, the latter of which are a vital food source for seals, whales, and penguins. Salps are filter-feeding tunicates that float through the water column, sometimes forming long salp chains, consuming phytoplankton and using jet propulsion to move. Read about their complex life history in “The Watery World of Salps," by Larry Madin of the Woods Hole Oceanographic Institution. Head to our blog to learn about how non-native tunicates and other marine invasive species are threatening Alaska's coastline.