BREWSTER, Mass. (AP) – At least nine pilot whales and 24 dolphins died after stranding on the shores of Cape Cod Bay, and experts said Friday’s snowstorm may have contributed to their deaths.

Five of the whales and seven of the common dolphins had to be euthanized, while the rest of the animals were found dead, according to Kristen Patchett, stranding coordinator for the Cape Cod Stranding Network.

“There were signs that they were going into shock,” Patchett told the Cape Cod Times. “It’s always a tough decision to put an animal down, one that we take very seriously, but in (this) case it was clear that it was the right thing to do to prevent suffering.”

Necropsies were to be performed Sunday on several of the animals.

Officials suspect that high winds and strong tidal fluctuations from Friday’s storm caused the dolphins and whales to become trapped in shallow water. However, the network says illnesses also can contribute to strandings.

The stranding network was notified of several animals in trouble Friday evening, but road closures and storm conditions prevented its members from responding.

Every year, the stranding network responds to an average of 204 strandings of marine mammals. Mass strandings are not rare: 18 Atlantic white-sided dolphins stranded on Massachusetts beaches during a storm in April 2003, and more than 50 pilot whales on Cape Cod in July 2002.

Pilot whales, which have a rounded head and slight beak, measure up to 20 feet and weigh up to three tons, making them second only to the killer whale in size, according to the American Cetacean Society’s web site.

Common dolphins, which are roughly eight feet long and can weigh nearly 300 pounds, have colorful hourglass patterns on their sides, curved dorsal fins and long, thin flippers. They travel in herds of hundreds if not thousands.

On the Net:

American Cetacean Society: http://www.acsonline.org/