Pod of seven orca are still in the Pāuatahanui inlet in Porirua Harbour

A pod of seven orca are still in the Pāuatahanui inlet in Porirua Harbour after swimming into the shallow body of water, probably chasing eagle ray that frequent the area, last Saturday morning.

The Department of Conservation (DoC) said that the animals, who are on the nationally critical list, "have been periodically eating, sleeping and just generally having a good time", but that the constantly shifting sands from local currents and the added problem of silt run off from the land could impede their ability to find their way back out to the open ocean.

DoC have been working with orca expert Dr Ingrid Visser, working remotely, the Orca Research Trust, local iwi and HUHA (Helping You Help Animals) to monitor the pod's behaviour and to ascertain if they can negotiate their way to freedom.

Visser had assisted in the attempted rescue of orca calf, dubbed Toa, who became separated from his pod in July. Unfortunately, Toa died when his condition deteriorated while a search went on for his family.

Dr Ingrid Visser filming male orca calf Toa playing with bull kelp in his pool at the Plimmerton Boating Club in Porirua in July. Photo / Mark Mitchell

An attempt was made to try to encourage the orca to deeper water using a small flotilla of boats.

"The orca appear to be having difficulty finding their way out of the inlet," said a DoC spokesperson on Wednesday morning. "This may be due to the shallow waters. This was indicated yesterday when attempts to gently shepherd them out of the inlet with four boats were unsuccessful."

Visser was not in favour of the action however, recommending against driving them out from the inlet.

"Our information suggests that plans may be under way by the DoC and Project Jonah to attempt to force the seven orca out of the harbour. I believe that this is not in their best interests based on current evidence," Visser said in a written statement.

She said that the orca frequent shallow harbours and are currently behaving within normal parameters, feeding on rays and, even, sleeping.

An adult male had stranded on August 27 but managed to free himself and was not in any danger, Visser said.

"From the video today we are able to see that his dorsal fin shows less evidence of drooping," Visser said. "Although we have concerns for this male, he appears to be on the road to recovery and disturbing him by chasing him is not good for his welfare."

DoC remain concerned for the pod given the time they have been in the inlet, with each low tide posing a risk one of or more of the pod may strand.

The tidal range within the inlet has been decreasing DoC said, and that the tidal forecast for Thursday shows that the tidal range will increase, with high tides getting higher and the low tides, lower. A higher tide makes it more likely the orca may be able to exit the inlet.

"Decisions on the actions we are taking are being made based on advice from marine mammal specialists, including from DoC and Project Jonah, and some international expert advice also," the department said in a media release. "We have also had contact with Ingrid Visser of the Orca Research Trust and her advice has been taken into account."

"As with any work with wildlife in the wild, DoC is seeking to ensure all people are kept safe and that the welfare of the orca is closely monitored to ensure decisions and actions are measured and well-informed. This remains a complex, challenging operation. The team working on a solution greatly appreciate the engagement and encouragement people have expressed," they said.