Starfish across a huge swath of the West Coast have died from a grim disease that causes lesions on the creatures that literally cause them to waste away, decaying and dissolving into white, gooey blobs.
This year starfish, also commonly referred to as sea stars, have been found dead in West Coast tide pools as far north as Alaska and south down to Orange County, Calif. At least 10 species of sea star have been reported dead from the so-called sea star wasting disease, according to a report from the University of California, Santa Cruz, center for Ecology and Evolutionary Biology.
In some tide pools, as much as 95 percent of the sea star population has been found dead, the Santa Rosa Press Democrat reported. Marine scientists and passersby along the coast have found the puddles of "goo" the disintegrated starfish turn in to after their lesions spread, causing their arms to fall before they waste away. The progression of infection to disintegration can take a matter of days or weeks.
"They essentially melt in front of you," Pete Raimondi, chairman of the Department of Ecology and Evolutionary Biology at UC Santa Cruz's Long Marine Lab, told the Press Democrat. "We've never seen it at this scale up and down the coast," Raimondi said.
Outbreaks of sea star wasting disease have occurred before, notably in 1983-84, but this year's outbreak appears to be much more widespread, and its full extent is unknown.
"Signs of sea star wasting disease have been popping up on both the East and West Coasts of the United States, as well as reports globally," UC Santa Cruz marine scientists wrote on their Pacific Rocky Intertidal Monitoring blog. "Reports of sea star disease and mortality on the East Coast began showing up in articles during July of this year. On the West Coast, sea star wasting was first documented in June ... by September observations were much more widespread, with accounts of diseased, dying and dead sea stars from numerous locations along the West Coast."
The most-affected sea star species is Pisaster ochraceus - orange and purple starfish typically abundant in tide pools.
The cause of this wasting event is still unknown, the researchers said, adding that a multi-institutional effort to identify the pathogen or pathogens is underway.
Click here to see a video about sea star wasting disease in Vancouver.