Sea stars, also known as star fish are dying by the tens of thousands up and down the West Coast and scientists don’t know why. The first species that was known to have become infected by the mystery disease was the sunflower starfish, which was documented with the as yet unidentified disease in June 2013. Currently, 12 species of sea stars are suffering from the disease, currently called sea star wasting syndrome. The symptoms, which infect both wild and captive sea stars, include white lesions on the arms of the sea stars and the self-tearing of arms completely off from the main body. The infected sea star then disintegrates within a few days.
Jonathan Sleeman, director of the US Geological Survey’s National Wildlife Health Center said in a December 2013 USGS National Wildlife Health Center statement that the two species that are most affected are Pisaster ochraceus (purple sea star or ochre starfish) and Pycnopodia helianthoides (sunflower sea star). According to the statement, entire populations of sea stars have died in Puget Sound and the Salish Sea (Washington/Canada) as well as along the California coast.
The scientists have not yet determined the exact cause of the disease but are working with the Monterey Bay, Seattle, and Vancouver, B.C. Aquaria; University of California–Santa Cruz and UC Davis/SeaDoc Society; Wildlife Conservation Society; Western Washington University; Cornell University; Roger Williams University; and a veterinary pathologist from Northwest ZooPath, to determine the cause of the wasting syndrome.
The West Coast of the United States is no stranger to sea star die offs, according to the National Wildlife Health Center. In 1983, the sea star Pisaster ochraceus, a top predator in the intertidal zones of the west coast, was almost completely killed off from California tide pools and a smaller scale die off occurred in 1997. On the east coast, a smaller but similar outbreak occurred in the Spring of 2013 on the East Coast of the United States.