What killed the sea stars? Canadian researchers unlock 12-year-old mystery

The paper detailing the four-year research project and its findings were published online in the peer-reviewed journal Nature Ecology & Evolution on Monday.

A team led by researchers in British Columbia has solved the mystery of a gruesome disease that has killed billions of sea stars along the Pacific coast of North America, more than a decade after the die off.

Melanie Prentice, the lead author of a new study, recalls a moment of “not really believing it” when researchers found a strain of bacteria that was abundant in diseased sea stars and absent in healthy ones.

“My initial reaction was like, ‘Okay, so I’ve done something wrong,'” she said.

Prentice said the team spent months trying to disprove their findings, ultimately confirming they had cracked the code of the disease.

They found the bacterium Vibrio pectenicida is a clear cause of sea star wasting disease.

“(It’s) a question that researchers have been trying to answer for about 12 years, so we’re beyond thrilled,” said Prentice, a research associate at the Hakai Institute and the University of B.C. department of earth, ocean and atmospheric sciences.

The paper detailing the four-year research project and its findings were published online in the peer-reviewed journal Nature Ecology & Evolution on Monday.

Alyssa Gehman, who helped launch the project in 2021, described the disease as “gruesome,” causing sea stars to develop lesions, lose their arms and “disappear into mush” about a week or two after exposure to the pathogen.