In all, at least nine pilot whales and 24 dolphins died. Five of the whales and seven of the dolphins had to be euthanized, while the rest were found dead, according to Kristen Patchett of the Cape Cod Stranding Network, a group that works to free stranded 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. Illnesses also could have contributed to the strandings, the network said.
The group was notified of several animals in trouble Friday evening, but road closures and a snowstorm that dumped more than a foot of snow on parts of New England prevented members from reaching them.
Necropsies were to be performed Sunday on several of the dead animals.