Since June 2013, millions of sea stars along the West Coast have disintegrated and died. Scientists have relentlessly tried to identify the cause of the “sea star wasting syndrome.” (See map of locations with outbreak.)
Typically, the first signs of an afflicted sea star are white lesions appearing on its body. Shortly thereafter, sea stars lose their limbs and their internal organs disintegrate. Although sea stars have the ability to regenerate limbs, the disease often progresses too quickly for them to recover. The exact cause of this disease is unknown. Scientists believe that sea star wasting syndrome may be due to a viral or bacterial infection, and could be exacerbated by increased water temperature. Populations of the ochre and sunflower sea stars, two common West Coast species, have been hit especially hard. Similar die-offs have occurred in the past, but never at the magnitude we see today, and over such a wide geographic area.