Sea Star Scourge

For the past two years, sea stars along the Pacific coast have suffered catastrophic die-offs. The disappearance of these key predators could have profound effects on their tide pool and near-shore ecosystems.

In collaboration with UC Santa Cruz and other institutions, biologists at Cornell University identified a “sea star associated densovirus” as the most likely cause. Although the densovirus was a novel discovery for researchers, the infectious agent was found in museum specimens of sea stars collected in 1942. The study was published in the Proceedings of the National Academy of Sciences.

“The question is why a virus that’s been around for years went rogue, or whether environmental stressors made the sea stars more susceptible,” said Peter Raimondi, UCSC professor and chair of ecology and evolutionary biology. There may be good news, though.

“In the last six months, we’re seeing more sea star babies than we’ve seen in some places for the last 15 years,” said Raimondi, who leads the Pacific Rocky Intertidal Monitoring Program. “If the disease is gone, this new generation could replenish populations more quickly than expected.”

Marm Kilpatrick, associate professor of ecology and evolutionary biology, and Melissa Miner, a research specialist at Long Marine Laboratory, also contributed to this study.