Wasting found in multiple Kachemak Bay sea stars

May 12, 2015

UAF News

Photo by Brenda Konar. A sea star photographed on Elephant Island in Kachemak Bay this spring displays lesions typically caused by wasting disease.
Photo by Brenda Konar. A sea star photographed on Elephant Island in Kachemak Bay this spring displays lesions typically caused by wasting disease.


Deborah Mercy
907-274-9698
05/12/2015

Decaying sea stars suspected of having wasting disease were discovered last week in Kachemak Bay.

Brenda Konar and Katrin Iken, researchers with the University of Alaska Fairbanks School of Fisheries and Ocean Sciences, found the sick sea stars while surveying long-term monitoring sites for Gulf Watch Alaska.

Thought to be caused by a virus, the sickness starts with lesions on the skin and culminates with the disintegration of the animal. Wasting disease currently is killing sea stars along much of the Pacific coast, ranging from Baja California north to Southeast Alaska. Similar die-offs occurred in the North American Pacific in the 1970s, '80s, and '90s but not at this magnitude and not in Alaska.

“Many scientists thought the disease was not going to come here because our waters are too cold,” said Konar.

The diseased sea stars were found in and around tide pools on Elephant Island. Damage ranged from lesions to near complete decay, with only one arm remaining. Konar said the lesions are usually the first sign of the disease. Most of the sea stars were in the genus Evasterias, a very common type in this area, but one was a Pisaster, which is much more rare in Kachemak Bay.

Konar said observers have reported seeing individual diseased sea stars in Kachemak Bay in the past, but this is the first sighting that involved more than one or two individuals and that occurred in the more oceanic part of the bay.

Sea stars are top predators that add diversity to their ecosystems. They prevent other organisms, such as mussels, from taking over and pushing out other species. If that were to happen, it could have a ripple effect throughout the entire ecosystem.

“This is definitely cause for concern,” said Konar. “We are going to keep monitoring these sites. We’ve contacted the sea star wasting folks in California who run the program. We are on their map.”

“I wouldn’t call it an epidemic“ said Konar, “but I think we can safely say it is probably here.”

ADDITIONAL CONTACT: Brenda Konar, 907-388-6745, bhkonar@alaska.edu

ON THE WEB: 
Information about sea star wasting disease: seastarwasting.org
Gulf Watch Alaska: www.gulfwatchalaska.org/

DM/5-12-15/284-15