Scientists identify bacteria behind West Coast sea star die-off

The big picture: A new study led by researchers in British Columbia found that a bacterial microbe called Vibrio pectenicida was the culprit behind the disease, which causes sea stars to lose their arms and ultimately dissolve in a grisly death.

What they did: Alyssa-Lois Gehman, a marine ecologist who led the study, said the team looked at the sea stars' coelomic fluid — essentially their blood. Previous research had mostly focused on tissue samples from the creatures.

What they're saying: "For me, it's the discovery of the decade," Drew Harvell, a disease ecologist at the University of Washington, told the New York Times.

Between the lines: One species particularly hard hit was the sunflower sea star, which can grow up to 24 arms and measure 3 feet across.

• They are voracious predators of purple sea urchins and, when they died off, urchin populations exploded.
• Those urchins ate their way through kelp forests up and down the West Coast, leaving many areas barren of the vegetation that supports creatures from tiny invertebrates to giant gray whales.

The bottom line: Naming the pathogen marks a turning point in recovery efforts — but scientists still don't know how it spreads or where it originated.