MEXICO CITY, Feb. 18 — Mexican authorities are investigating the mysterious deaths of eight whales found washed ashore along the Sea of Cortez last month, an unusually large number that suggests someone or something is killing them off.
The whales come from several plankton-eating species and apparently died at sea in November and December, biologists said. But they do not show any signs of having been caught in long-line fishing nets, which sometimes suffocate the mammoth animals. Nor have biologists found any signs of a toxic spill or outbreak of disease that would account for their deaths.
"Right now it's a mystery," said Luis Fueyo, an assistant federal prosecutor for environmental crimes, who is overseeing the investigation. "We have a puzzle."
The first sign something was wrong came on Jan. 4, when the remains of two humpback whales were spotted on the shore near the town of El Dorado in Culiacan State. Scientists determined they had died in early November. Since then, six more giant bodies have turned up, among them a third humpback, a minke whale, a fin whale and a baby gray whale. Three bodies were discovered on Jan. 18 during an aerial search of the Sinaloa coast.
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http://www.nytimes.com/2006/02/19/international/americas/19mexico.html?_r=1&oref=slogin