'We have not seen anything like this before': Mass ray deaths puzzle beach cleaners

Author: NZ Herald,
Publish Date: Mon, 29 Jun 2026, 4:33pm

Biosecurity New Zealand is investigating what caused more than 30 dead rays to wash up at a Porirua beach on Sunday.

A social media post by the Petone Beach Clean Up Crew said dozens of eagle rays and two rig sharks were discovered “all relatively close in one area” and still appeared fresh.

“We have not seen anything like this before,” the post read.

It said the incident had been referred to the Department of Conservation (DoC).

One of 30 dead eagle rays that washed up at the Porirua inlet. Photo / Facebook, Petone Beach Clean Up Crew

DoC senior marine science adviser Karen Middlemiss said the department was “aware of the mass death event” but noted that eagle rays and rig sharks are not protected species.

Biosecurity New Zealand team manager, aquatic health Mike Taylor said specialist staff would visit the site today to collect and test samples to rule out exotic disease as a cause.

“We suspect that the mortality could have happened due to the recent stormy weather or potential predatory action from orcas,” Taylor said.

It comes after a period of severe weather in the capital, which caused seabirds to be injured.

The Herald yesterday reported that Flock Birdcare Wellington had seen an increase in injured birds, crediting the recent “crazy weather”.

Orcas are no strangers to Wellington’s waters, with drone footage showing the creatures hunting stingrays off the city’s south coast earlier this year.

Stingrays are a staple food of orcas, with the predators regularly patrolling shallow waters, beaches, and harbours around the country to hunt rays. They often herd them right to the shoreline and sometimes even beach themselves in the process.