Monterey County

Scientists scurrying to determine what's killing starfish

What's killing starfish?

MONTEREY, Calif. - They are the stars of the sea, but now sea stars, or you might call them starfish are dying. The big mystery is why? Scientists are struggling in a race against time to find what's causing a disease that's been killing hundreds of thousands of starfish since last summer.

A widespread disease is wiping out species after species, but scientists are closer to finding out what's killing them. The disease results in gruesome deaths that physically tear and melt their bodies apart.

Hundreds of thousands of sea stars have been dying since last July from as far north as Vancouver, all the way down to Mexico. Last summer, Central Coast News got a first-hand look at what experts are calling the starfish wasting disease when we went out with Pete Raimondi and his UC Santa Cruz evolutionary biology students. They have found that in some cases, the starfish's arms rip themselves from the rest of the body. In the end, the starfish turns into a slimy gooey substance.

"It just looks like a grave yard out there, just arms scattered everywhere," said Sarah Wilson, a UCSC student and researcher. "Some are just one armed sea stars two, three, some are doing a little better with four arms, but still its not what it should be."

A year ago, all scientists knew was that sea stars were losing limbs and eventually disintegrating, and they didn't know why.  Four months later, Raimondi said, it was even worse than he suspected.The disease is showing no indication of abating.

Marine biologist like Raimondi say the sea star wasting disease is the most catastrophic disease of its kind that they have ever seen, because it has rapidly spread across species of starfish.

So far, the mysterious killer has been decimating 18 different species along their entire range on the North American Pacific Coast.That launched a massive study project from Long Marine Laboratory to collect data on sea stars and the disease.

Now a year later, they're seeing healthy star fish in some tide pools in Pt. Pinos in Monterey Bay , but they know the disease has been here and taken it's toll. There are usually about 20-24 ochre stars, but after recent data collection from the group there were none.

"That's the first time that's happened," said Christy Bell, a marine biologist.

With a mortality rate as high as 95%, entire starfish populations from as far north as Alaska to Southern California and Mexico have been wiped out,and even the bat star's previous immunity to the disease isn't safe anymore.

"We thought 'OK,' this guy is immune," said Raimondi. "(But) we are starting now to see them waste away. It's not a little bit either - they are really going now, big time!"

The dramatic loss of sea stars caught the attention of Cornell Microbiology Professor Ian Hewson, all the way across the country in Ithaca, N.Y.

He says the reason this disease is so difficult to pinpoint is that sea stars are unique. Instead of a blood stream they have sea water running through their veins. Sea water itself contains about a million bacteria per mil.

"I can say there is something on the order of about two to five thousand species of bacteria that occur within a healthy sea star," Hewson said.  "So that's an idea of how we are trying to pull a needle out of the hay stack."

He compares tracking this sea star disease to HIV in the early 80's.

"If you were to look at all the viruses that were in patients with HIV, you probably wouldn't have seen the root cause of human immunal deficiency," Hewson said. "You probably would have seen a whole host of other types of viruses and bacteria. So it's tricky to sort out what is a pathogen and what is not."

Although the answer to what's infecting sea stars is hiding in a vast ocean, Hewson says they're close to the answer.

"Based on some initial analysis and work we have done this year, we believe we are relatively close to finding out what is the cause of the disease," said Hewson.

He believes it's a pathogen, and he has ruled out some viruses and bacteria, he's not ready to say for sure. what the cause is.

"Hopefully that will occur fairly soon," Hewson said.  "I can't be more specific than that."

Experts hope to have an answer in three to four months from now, but they caution that you can't put a time limit on this type of research. UC Santa Cruz biologists are asking for the public's help in documenting these diseased starfish. If you happen to find any while diving or hanging out at the beach take pictures and submit the information here.

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