At least five whales out of a pod of six are dead after getting stranded on Cape Cod this week, rescuers said Wednesday.
One of the pilot whales remained unaccounted for Wednesday afternoon, according to the International Fund for Animal Welfare, which had been monitoring the stranded animals since Monday evening.
A calf in the pod initially died overnight into Tuesday, but rescue workers had managed to return the remaining whales into the water off Eastham, according to the IFAW. However, on Wednesday morning, some of the whales were discovered back in the Wellfleet Bay Wildlife Sanctuary.
By the afternoon, four of the surviving pilot whales had been euthanized, having struggled through three days of being stranded, the IFAW said.
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"The team made the difficult decision to euthanize these animals as we knew rescue efforts at this stage were no longer going to be possible. It’s the most humane decision to make in a circumstance like this," a representative for the organization said in a statement.
The IFAW is a global nonprofit group that works to help people and animals coexist.
Experts say the geography of the Cape Cod peninsula can create conditions for strandings. The area is known as having the most dolphin strandings in the world. Earlier this year, two pilot whales died after they became stranded off Chatham.