IFAW via Reuters
Two dolphins are prepared for release Monday into Cape Cod Bay.
BOSTON -- Nineteen dolphins that stranded themselves along Cape Cod have been treated and released, but several dozen others have perished since the string of strandings began last Thursday.
Eight that stranded alive did not survive, said Katie Moore, manager for marine mammal rescue at the International Fund for Animal Welfare, while another 32 washed ashore already dead.
Of the 19 survivors, one was a calf and another a pregnant mom.
Strandings typically happen from January to April, but the pattern this year is unlike past years, when just one dolphin or a group would be found on a single beach, she said.
"I've been doing this for 15 years and this is only the second season I've seen it like this," she said.
Julia Cumes / AP
A dolphin is given a hearing test before being released back into Cape Cod Bay at Scusset Beach on Saturday.
"It feels like stranding after stranding after stranding," Moore added. "It's definitely out of the ordinary."
The dolphins began beaching themselves on Thursday, with a single dolphin stranded near the town of Wellfleet, said IFAW spokeswoman Kerry Branon.
On Saturday, the busiest day for rescuers, at least 37 dolphin were found spanning five towns along 20 miles of Cape Cod, Branon said.
Cape Cod is among the top locations for the phenomenon worldwide, she said. Beaching of dolphins has been happening for centuries, but researchers are still trying to determine what brings the dolphins to Cape Cod Bay this time of year.
The group actions tend to happen, in part, because dolphins operate with a group mentality, where many others may follow one animal toward shallow water, IFAW said.
The animals, which tend to get stuck on the bay side of the hook-shaped Cape Cod, are assessed by rescuers and then taken to deeper water on the ocean side and released.
Marine biologists check for signs of stress and body condition, among other factors, and tag the dolphins with an identifier before release.
A handful of animals have also been affixed with a tag to track movement and transmit data to researchers, Branon said.
"We also were able to test the hearing on one animal as well ... important data for our project which will hopefully aid in conservation measures to protect marine mammals from ocean noise," Moore said in a statement.
Moore said this year's series of dolphins stranded on beaches reminded her of the 2005-2006 winter, when dolphins beached themselves over a 40-day period.
Reuters contributed to this report.
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