Rena: Pollution threat to endangered orca whales

Orcas. Photo / Dr Ingrid Visser

Orcas have been sighted coming from the area where oil has spilled from the container vessel Rena, sparking fears the endangered species may have ingested the toxic substance.

Bay of Plenty resident Paul Carter spotted three New Zealand orca whales passing Pukehina beach at about 6.45am yesterday, close to the shoreline.

"There was one fairly large male and two females. They would have been about 30m off the shore. They were heading towards Whakatane.

"They chase the stingrays. When they're in close like that, they're looking for breakfast."

Pukehina beach is east of Maketu, one of the areas worst affected after the Rena ran aground on the Astrolabe reef on October 5, spilling tonnes of oil.

Mr Carter said the whales appeared to have travelled from the direction of Mt Maunganui and Papamoa, areas included in the exclusion zone around the stricken vessel.

Orca biologist Dr Ingrid Visser said there was a high chance the whales had ingested oil while making their way along the coast.

"This is devastating for these individuals because it has been shown from scientific studies that exposure to oil like this causes liver damage, chronic cell infiltration, stomach ulcers, jaundice, inflammation, you name it. It's major for these mammals.

"They're mammals so when they breathe in the fumes it gets to them, it's toxic for them."

She said fewer than 200 orca lived around the New Zealand coastline, and they had the highest endangered threat rating available for animals.

There was nothing to stop the mammals going through the restricted area, and the oil should have been cleaned up sooner, she said.

"You can't just put up a stop sign and say turn around guys ... There's nothing you can do and that's why these sorts of things need to be prevented."

"In terms of how this is going to affect marine mammals long term, it's not something that is just going to go away."

Blue whales have also been sighted making their way through the area's waters at this time of year.

Mr Carter said the seals and penguins normally on Pukehina beach at this time of year had been absent since the vessel ran ground.

Dr Visser asked for orca sightings on 0800 SEE ORCA (0800 733-6722).