Bizarre, Glowing Sea Creatures Bloom in the Pacific

After three years of unprecedented warm water along the U.S. West Coast, sea temperatures in 2017 had finally cooled. Fat shrimplike krill had returned and again were providing rich meals for salmon. Sea lions and other marine mammals were no longer washing ashore shriveled and starving. Things appeared to be getting back to normal. Beginning this spring, millions of bizarre primitive-seeming jellyfish-like bioluminescent sea creatures—some more than two feet long—started gumming up research nets, glomming onto fishing hooks, and cascading onto beaches along the West Coast.

These stubbly gelatinous animals called pyrosomes (each is technically a colony of other multi-celled animals called zooids) are cone-shaped tunicates normally found in the tropics, but they are spotted once in a while as far north as British Columbia. But this spring they started swarming the eastern Pacific in masses never before recorded, stretching from Oregon to the Gulf of Alaska.

"It’s really weird," says Jennifer Fisher, a faculty research assistant with Oregon State University’s Hatfield Marine Science Center. "I’ve never seen anything like it." Neither has Rick Brodeur, a research biologist at the National Oceanic and Atmospheric Administration’s Northwest Fisheries Science Center in Oregon. And he’s been studying jellies and […]