(After this story went to press Russel Barsh released the following information: More Indian Island seastars were stricken by wasting syndrome in mid-July as hot weather continued. A systematic survey of hundreds of Ochre stars in the inter-tidal zone (rocks and beaches) found that the proportion of “sick” animals had risen to 49 percent, the highest rate yet observed. Hundreds of seastars appeared to remain unaffected. It is important to bear in mind that seastars tend to avoid hot, drying midsummer weather by retreating into sub-tidal waters. This would leave a disproportionate number of diseased seastars visible on beaches, since the first visible effect of wasting syndrome is loss of control of water pressure and mobility. Potential for recovery of this population remains good: ochre stars produce millions of eggs, and have already reproduced this year.)

They are dying – wasting away, drying out and disintegrating into sun-bleached piles of dust. Limbs detach from the body and seem to melt away.

The victims are ochre sea stars. Researchers are calling the sickness sea star wasting syndrome.

“We have evidence that an infectious agent is involved, but it is too soon to say yet whether it is a virus or a bacterium,” said Drew Harvell, a marine epidemiologist at Cornell University.

Some scientists are making ominous predictions that all the ochre sea stars near Indian Island could be dead soon, whereas other research points to only a 7 percent infection rate.

The questions are: what exactly is this syndrome and are we looking at an extinction?

Sea stars belong to the class Asteroidea, which is hypothesized to be at least 450 million years old. There are more than 20 species of stars in the San Juans, and Harvell says that most of them have been reported to have some sign of disease in intertidal and sub-tidal surveys.

Researchers like Harvell gave the disease its name due to the rapid nature of the sickness and its deterioration of the species. The wasting disease hits both densely populated areas as well as areas with only a few stars.

Harvell said the disease happening in the San Juans is similar to what is occurring to millions of sea stars from Alaska to Mexico and is being studied by various teams, including about 40 biologists from many west coast universities and all the major aquariums.

“This is slow, careful work that takes repeated experimentation in the lab and many tests to verify,” she said.

Harvell told PBS reporters in June that all the ochre (pisaster ochraceus) sea stars at Indian Island survey sites would be dead at the end of the month.

She told the Sounder that there is now good news.

“At the East Sound site they have not all died, but they did go from none visibly sick in May to just over half sick and quite a few dead,” she said.

Harvell’s background is as a researcher studying epidemics in the ocean. She has worked for more than two decades on outbreaks of coral reef invertebrates; for the last three years she has focused on a seagrass disease in the San Juans.

When the epidemic of sea stars first took off in the Northwest last August, Harvell turned her attention to the five-rayed purple and orange ochres.

At this point she said it is premature to talk about extinction.

“We expect the stars to recover,” she added. “But this is such a big, widespread event, it could take a long time.”

There is additional hope in the San Juan Island sites that are holding strong, so it’s not yet clear what the impact will be.

For one researcher, it is clear – it’s not as drastic as reported by Cornell researchers.

Russel Barsh, director for the Lopez-based laboratory Kwiaht, has been monitoring the wasting disease at Indian Island since last fall on every low tide cycle. On June 29 he examined 658 ochre stars at Indian Island. He concluded that 7 percent were unmistakably diseased. In the last five months he had observed that about 1-2 percent indicated illness.

He did say the syndrome is currently much higher on the west side of Orcas, where visitors tend to walk along the beach, than on the rockier and less walkable east side.

“A connection is possible. Pathogens can be carried on human hands, boots and sandals,” he added.

Other variations of the sites may also cause discrepancies in how the disease affects the species. The two sides of the island differ in other ways as well. The west side has stronger currents, a steeper drop-off and more seaweed.

Another possible cause of the syndrome may be warming waters due to climate change. According to NOAA, the chance of El Niño  for 2014 is 70 percent during the Northern Hemisphere summer and reaches 80 percent during the fall and winter.

Biologist Carol Blanchette told PBS that die-offs of sea stars in Southern California occurred during warmer El Niño years — 1982-1983 and 1997-1998.

The sea star population in that area did recover.

Barsh said another cause could be related to birds that eat the stars. Although pathogens such as bacteria, viruses and fungi tend to infect members of the same species, or closely related species, it is unlikely that any seagulls will get sick. It is possible that seagulls can help reduce the spreading of the disease because they are eating the dying sea stars. On the other hand, the gulls could potentially spread the disease in their fecal matter.

The data Barsh collected has been limited to the inter-tidal zone, a small portion of the habitat used by ochres around Indian Island, which leads him to ask whether diseased sea stars are more likely to be seen in shallower water because they have lost some mobility, or because as they begin to die they get washed up.

The loss of sea stars may be even more tragic because they are a keystone species, meaning their absence has a profound effect on the environment.

The species’ importance was recorded by zoologist Robert T. Paine, who, according to the “American Scientist,” started flinging ochres off selected patches of rocky shore along the Olympic Peninsula in 1963. His experiments showed that in the absence of predatory starfish, mussels took over what had been a rich and diverse area.

“Carnivorous animals are important,” said James A. Estes, who worked extensively with Paine, in a public address in 2002. “We have to stop thinking of them as passengers on this earth and start thinking of them as drivers.”