stranded,dolphin
© Cape Cod Times/Steve HeaslipRescue workers on Lieutenant Island in Wellfleet this afternoon, where six dolphins have stranded. At least two have died. Ten other dolphins stranded in an area further north in Wellfleet today. Two of those were rescued and may be released later in Provincetown.

At least 10 more dolphins stranded themselves on the beaches of Cape Cod this week, a Cape-based animal welfare group said. The strandings raised the annual total to more than 200 in just three months, an unusually high number that has left scientists scrambling to find a cause.

"This week we had 10 common dolphins strand in various locations including Brewster, Wellfleet, and Orleans," Michael Booth, spokesman for the International Fund for Animal Welfare, said. "We had four strand on Monday - one in Wellfleet and three in Brewster."

Six more dolphins stranded Tuesday -- two in Wellfleet, three in Brewster, and one in Orleans, Booth said.

Nine of the 10 were released to the ocean; the 10th had to be euthanized because it had already sustained some injuries, he said.

In addition to rescuing and treating stranded dolphins, Booth said, the group has helped to lead nearly 100 dolphins out of dangerous situations since Jan. 1, including six that were herded out of the Herring River in Wellfleet on Monday.

"Those are animals that have been in problematic areas where they would have surely stranded had we not gone out and herded these animals into deeper water," he said.

The most recent strandings come after the end of what was the largest single-species stranding event on record in the Northeast. Between Jan. 12 and Feb. 16, 179 dolphins were stranded on the shores of Cape Cod.

In total this year, 208 dolphins have stranded themselves on Cape Cod beaches. Of the stranded dolphins, 94 were found alive and 114 were already dead when rescue groups got to them. After treating the live dolphins, IFAW was able to successfully release 71 dolphins into deeper water - a success rate of about 76 percent.

"It's an all-time high for us," Booth said. "We have gotten better and better through the years. We did have a success rate before this of around 60 to 70 percent, but now with this particularly high stranding season, we've got that percent up to 76 percent, which is great."

Booth said the month of near-daily strandings allowed the group to put its skills and resources to the test and hone the skills of its small army of volunteers.

"It gave us the opportunity to put our systems in place. We have been fine-tuning that for a number of years now," Booth said. "To be able to consistently go out and rescue dolphins and have this high of a success rate is something we are very proud of."