A mysterious disease is decimating several species of sea stars along the Pacific west coast and small parts of the Atlantic coast. Only one confirmed case of the disease has been found in San Diego waters off of Point Loma in early December. Areas to the north are experiencing mass die-offs, especially off the central coast of California. Scientists have named the disease “sea star wasting syndrome” and it affects all types of sea stars including the common star fish.
Sea star wasting disease starts with lesions and those lesions slowly dissolve the sea star, causing its limbs to fall off and making it too weak to adhere to rocks. Then, it slowly turns to mush, leaving behind a white sticky goo. It is estimated that, in some areas, more than 95% of the resident starfish have been killed in some tide pools. The disease is mostly likely spreading with the current, according to Keith Lombardo, chief of natural resources with the Cabrillo National Monument.
Scientists are baffled as to the cause and spread of the illness which was first noticed in ochre stars back in June 2013. Sunflower stars are also severely affected and both them and the ochre stars are considered keystone species for this disease. There have been mass die-offs from disease before, but those mostly affected one species. This disease has been discovered affecting at least ten species. Previous die-offs were never at the scale that the current die-offs are happening. Many scientists are concerned about biodiversity as the sea stars frequently feed on mussels and other invertebrates that often damage kelp and other sensitive species.
The University of Santa Cruz is enlisting citizens to report sick or dead sea stars to their citizen science website: www.seastarwasting.org. The site also has photos of what to look for and how the disease is affecting the animals. Like other citizen science projects, it is hoped that having more eyes looking out for the disease will help track the disease and narrow down a cause.