Sea Otters May Be Global Warming Warriors
Sea otters might be on the frontlines of the fight against global warming, according to a new study showing the fur-coated swimmers keep sea urchin populations in check, which in turn allows carbon dioxide-sucking kelp forests to prosper. Researchers from the University of California, Santa Cruz, looked at 40 years of data on otters and kelp blooms from Vancouver Island to the western edge of Alaska’s Aleutian Islands. They said they found that sea otters have a positive indirect effect on kelp biomass by preying on sea urchins.
Sea urchins greedily graze on kelp when otters are not around, but in the presence of the predators, urchins hide in crevices and eat just the plant scraps. More otters mean more kelp and since the plant is particularly good at capturing carbon through photosynthesis, this also could mean less CO2 in the atmosphere. The study, published in Frontiers in Ecology and the Environment, found kelp forests can absorb 12 times more carbon dioxide with otters around than if the plant were subject to sea urchins.