The recent heatwave that swept the West Coast of the U.S. and Canada claimed many human casualties, including at least 486 sudden deaths in British Columbia. But when the thermometer reached an unprecedented 121 degrees in Lytton, B.C., a less-heralded heat-related tragedy was happening on the coast as a billion sea creatures roasted to death.
Christopher Harley noticed a putrid odor at Kitsilano Beach in Vancouver during the heatwave. The University of British Columbia marine ecologist followed his nose to find dead intertidal animals strewn across rocks on the beach. Harley and fellow researchers then checked on nearby coastal areas and discovered similar devastation. As CBC reports, the researchers saw “endless rows of mussels with dead meat attached inside the shell, along with other dead creatures like sea stars and barnacles.”
Mussels can endure short spurts of 100-degree weather. But when the rocky shoreline reached 122 degrees, as measured by Harley and his team, the poor mussels were toast. Harley compared their situation to that of “a toddler left in a car on a hot day.” After all, it’s not like a mussel, starfish or anemone can stroll off somewhere to look for shade. “And on Saturday, Sunday, Monday, during the heat wave, it just got so hot that the mussels, there was nothing they could do,” Harley said.
Harley estimates that more than a billion animals living on the shore of the Salish Sea perished in the heat dome event. He came up with this number by figuring out how many mussels would fit into a small area, then multiplying by the 7,000 kilometers of affected shoreline.
People might not care much about mussels, but the bivalve mollusks are an essential part of the ecosystem. Migratory birds and sea stars both eat them. Harley predicts that the mussels will recover in a couple of years, but sea stars and clams, which have much longer lifespans, will require more time to regenerate.
Lead image via Pixabay