The stranding and death of a 15m sperm whale is an example of how unhealthy our oceans are, according to a witness.

The whale came ashore near Dick Urlich Drive on Tokerau Beach, Karikari Peninsula, on Friday afternoon and was tossed about by the waves.

Department of Conservation staff and locals stayed with the giant mammal but it died in the early hours of Saturday.

Robert Urlich, who was born on Tokerau Beach, said sperm whales used to frequent the area but the whaling industry almost completely decimated the population. After commercial whaling stopping in 1923, it took a long time for the population to recover.

Advertisement

Whale deaths had increased in recent years, Urlich said.

"Recently, there have been a number of whale deaths worldwide; in fact, I think there have been an increase in the number of whale deaths and we don't know why that should be, exactly."

Urlich suspects the deaths are a result of microplastics which have been found in the ocean.

The effects were devastating, he said.

"It's not just the whales but the whole of the marine life, and not only the marine life but the birds that feed on the small fishes, they've been affected, too," Urlich said.

"It gets us too in the longer term – humans – and it's humans that have caused it in the first place."

On Saturday morning, a small crowd of onlookers watched in pouring rain as the whale was pulled ashore by a digger.

Urlich said once pulled ashore, samples would be taken from the whale and sent to a university to determine exactly what killed it.

Advertisement

After the samples were taken, the whale would be buried in the sand dunes.

Earlier this month, Indonesian villagers found the rotting carcass of a 9.5m sperm that had a large amount of plastic waste in its stomach.

Rescuers from Wakatobi National Park found the dead whale near the park in Southeast Sulawesi province after receiving a report from environmentalists that villagers were beginning to butcher it, park chief Heri Santoso said.

Santoso said researchers from wildlife conservation group WWF and the park's conservation academy found about 5.9kg of plastic waste in the animal's stomach: 115 plastic cups, four plastic bottles, 25 plastic bags, two flip-flops, a nylon sack and more than 1000 other assorted pieces of plastic.