The Yahoo News, 03 August 2006
Sea urchins dying off California coast
NEWPORT BEACH, Calif. - Hundreds of dead or dying purple sea urchins have washed up into tide pools at a Southern California marine refuge center in recent days, but no one is certain what is killing them.
"On Monday there were 200 or 300 that littered just the tide pool area," said Amy Stine, a supervisor at the Little Corona Marine Life Refuge. Normally, she said, she sees at most three urchin shells a day.
"Most of them that are now left on the shore are dead. The sea gulls are having a heyday with them," Stine said.
Some officials say the warmer-than-usual water, which holds less oxygen, may have suffocated the urchins. Ocean temperatures climbed above 75 degrees during the last couple of weeks when the region sizzled in triple digit temperatures, warming normally chilly waters along the coast.
"Water temperature is everything to marine animals," said Dennis Kelly, professor of marine science at Orange Coast College in Costa Mesa. "Their world tends to be a lot colder than ours, especially around here."
The tide pool landscape may also be a factor in the deaths, said Pat Leahy, director of the Kerckhoff Marine Laboratory in Newport Harbor. For purple sea urchins uncovered at low tide, the lack of constant cool tidal water and the hot surface temperatures might have been fatal.
Kelly said other possible causes could include naturally occurring pathogens, pollutants or overpopulation.