Something has wiped out virtually all the Sunflower starfish at a popular dive spot in British Columbia, Canada.
Staff at Vancouver Aquarium were alerted last month by a diver who had discovered large numbers of dead and decaying starfish off the coast of west Vancouver — and now they have just about disappeared in Howe Sound and Vancouver Harbour. It's thought that the epidemic, which causes the starfish to 'melt', has killed thousands of them, but the cause is still a mystery.
There has recently been a huge population explosion of Sunflower starfish (Pycnopodia helianthoides) in the area, reports The Canadian Press. The overcrowding that has resulted may have increased the risk of disease.
Some other species of starfish have also been affected.
Donna Gibbs, of the aquarium's Howe Sound Research and Conservation group said: "Whatever hit them, it was like wildfire and just wiped them out. We are seeing some babies, so we're wondering if they will survive."
There have been reports that similar die-offs have occurred in Florida and California, although researchers don't know whether it's the same epidemic, as it's difficult to run tests on specimens that have turned to goo.
P. helianthoides is thought to be the largest sea star in the world, with an armspan of up to 1m/40" in diameter.
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