New Zealand conservation officials and volunteers have successfully refloated one young whale from a pod of five that beached on the country's North Island.
The other four, all adult whales and understood to be Grey's Beaked whales, died on the west coast beach, an official said.
Local volunteers and Department of Conservation (DoC) staff successfully refloated the only surviving whale, a juvenile, and were hoping it did not become stranded again, DoC spokesman Des Williams said.
"There's some concern as to whether the juvenile is old enough to survive by itself," he said, adding that staff and volunteers had remained in the area to help it if needed.
The dead whales were to be buried in sand dunes nearby.
Grey's Beaked whales can grow up to 18.7ft long and have a distinctive long, slender beak.
They strand regularly on New Zealand beaches. Whale experts have been unable to explain why the highly intelligent mammals apparently swim into dangerously shallow waters and become stranded.