Twelve dead sperm whales have now been found on a South Taranaki beach in what the Department of Conservation is calling a rare event.

Photo: 123rf.com

Eight of them were found on Kaupokonui Beach last Thursday, three additional ones yesterday, and another one today.

The Department of Conservation said all of them were male but it didn't know why they had been stranded.

Its biodiversity ranger Callum Liley said biopsies had been taken of the mammals which will give them more information regarding their genetics.

There could be more dead whales from the same pod washed up somewhere else, he said.