A pygmy sperm whale about four metres in length beached itself at Mahia beach on April 10.
© JULIA LEPORACE
A pygmy sperm whale about four metres in length beached itself at Mahia beach on April 10.
A pygmy sperm whale was euthanised and another, which appeared injured, died after washing up on Mahia beach

The Department of Conservation (DOC) received a report that two pygmy sperm whales were stranded on Mahia Beach in the morning on April 9.

One measured two metres in length and the other four metres, which suggested they may have been an adult and a calf. Both were back out at sea before DOC arrived onsite.

But DOC east coast operations manager Chris Visser​ said the smaller whale beached itself again a few hours later.

"By the time DOC arrived it was not very active and may have been unwell, although it is hard to say what the cause may have been."

Concerns on welfare meant a decision was made to euthanise the whale, and it was buried.

On April 10, representatives from Ngāti Rongomaiwahine contacted DOC, advising that a pygmy sperm whale had beached, but died before DOC arrived at the scene. It was buried by the Rongomaiwahine representatives.

"We are unsure whether this whale is the larger one that beached the day before," Visser said.

Napier woman Julia Leporace​ was on holiday in Mahia when the stranding (on April 10) occurred and said it appeared the whale was injured.

"My husband and three other men tried to push the whale back to sea and at first it looked like it would swim away, but it ended up heading back. It was bleeding heavily and had what looked like a big cut under the tail," she said.

Gisborne resident Zoe Findlay​ was also on the beach with her children during the afternoon and said it looked like the whale may have had complications giving birth.

"There was a lot of blood, at first we thought it was a great white shark because it was thrashing around a lot, but then when we got closer we realized it was a whale."

Findlay described the experience as both "amazing and terrible".

"The boys [four of them] managed to push her out, but she came straight back in again. We went down a bit later, but she had died."

Visser said it was a common species to strand in New Zealand, but particularly in this area, indicating the whales probably lived offshore in the Hikurangi trench.

As they are usually an offshore, deep-water species, it is possible that animals that come close to shore and strand in New Zealand might have underlying health issues. Stranded animals of this species often pass away naturally or need to be euthanized.