Staff at the two North Olympic Peninsula marine life centers hope a study pinpointing a variety of densovirus as the likely cause of sea star wasting syndrome is only the beginning.
The Cornell University study published Monday in the journal Proceedings of the National Academy of Sciences is a great scientific breakthrough, but doesn’t help the remaining sea star population in the short term, said Shannon Phillips, an AmeriCorps volunteer at the Port Townsend Marine Science Center.
“There are 10 million viruses in every drop of seawater. It is amazing that they have narrowed it down to one,” said Phillips, who has monitored the sea star situation for the center.
The study did not find a cure for the disease.
“There needs to be a lot more information,” said Bob Campbell, facilities and education coordinator for the Feiro Marine Life Center in Port Angeles.
Both marine centers reported an 80 percent loss of sea stars in their tanks.
Port Townsend researchers reported an equal loss among wild populations in local areas.
A loss of 98 percent of sea stars in the wild was reported at a site west of Port Angeles.
The study showed that an ultraviolet light killed the virus and protected sea stars in the university’s tanks.
That wouldn’t work at either the Port Townsend or Port Angeles centers.
“It needs a closed system,” Phillips said.
Both marine centers’ systems pump fresh sea water into the tanks, which brings nutrients to the animals, then returns the water and animal waste to the harbor.
“We don’t want the water altered in any way,” she said.
Campbell said the sheer volume of water pumped through the system is too much to try to remove the virus with ultraviolet light filters.
“It’s a lot of water,” he said.
Phillips said that what happens in the tanks mirrors what happens in the bay, giving marine scientists an idea of what is happening in the wild.
Sea stars were dying of the wasting disease in the tanks before it was confirmed in the wild population nearby.
“We didn’t have a plot study then,” she said.
An Indian Island plot was established, about 150 feet square, which had 57 adult sea stars in a February survey by Port Townsend Marine Science Center volunteers.
On Nov. 5, there were only 12, a loss of 79 percent, Phillips said.
The marine science center’s exhibit tanks lost 80 percent of the sea star population.
Before the outbreak, there were 75 sea stars in the tanks, but only 15 remained Tuesday afternoon.
“We had 21 ochre stars, and now we have one,” Phillips said.
All six of the center’s giant sunflower stars died, she said.
She said that Tuesday morning, the center had to euthanize yet another star.
The science center has said it will not bring any new sea stars into the tanks until the outbreak is over, to leave them in the wild to repopulate the region.
At the Port Angeles marine center, Campbell said that 80 percent loss in the tanks sounded about right, but the actual number of sea stars that were originally at the center was never known.
The center began counting sea stars only after many had died, he said.
On Wednesday, only five ochre stars remained alive in the tanks, along with a few dozen of the more resistant blood stars and six-armed stars.
All of the Feiro sunflower stars and painted stars have died.
Volunteers from Feiro have undertaken a study of sea stars at Freshwater Bay, west of Port Angeles, where an overall loss of 98 percent was recorded, said Helle Andersen, survey organizer.
Sea stars in the tanks do reproduce, and some juvenile sea stars are washed into the tanks with the seawater and establish themselves there, so the tanks may naturally repopulate.
Typically, sea stars breed in February, with baby stars emerging in April, so marine center staff at both are waiting to see how well the sea stars rebound.
The Feiro tanks currently have a number of fingernail-sized baby six-armed sea stars thought to be the offspring of stars in the tank.
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Reporter Arwyn Rice can be reached at 360-452-2345, ext. 5070, or at arwyn.rice@peninsuladailynews.com.
