Searches by boat and air have failed to find a pod of orca that was spotted in Wellington region waters.
Searches continued on Tuesday across the wider west and southern coast of the lower North Island for the family pod of an orca calf which was stranded on 11 July.
Now named Toa, the orca has been receiving 24/7 care by a team of scientists, veterinarians, Department of Conservation (DOC) staff, Whale Rescue, HUHA, and local volunteers since becoming separated.
DOC marine species manager Ian Angus said they were conscious of how long it had been away from its mother and pod.
Rescue teams started off on a high this morning with the reports of a pod so close to the baby orca's location, but both aircraft and boats were unable to verify the reports in the surrounding areas, he said.
"People want a good news story, we're really hopeful that we can deliver upon it. But we've obviously got to do what's right for this individual animal."
Toa has been inside a 32,000 litre pool on site since stormy weather and large swells hit the area last Thursday.
While it was planned to relocate the orca calf back into its sea pen, unsafe stormwater and further forecasted bad weather has prevented that from happening.
"Tonight the orca will remain in the temporary holding pool, but we will review options tomorrow morning, factoring in weather conditions, any health warnings about the seawater in the harbour, and the calf's welfare", Angus said.
"We're very conscious the length of time the calf has been in our care, away from its pod and mother, is now over a week. That's not ideal for such a young wild animal"
Some scientists have spoken out against the ethics of containing the orca calf.
Massey University marine biology professor Dr Karen Stokin said finding the calf's family pod was only half of the problem
"There are no guarantees that even if Toa's natal pod could be located, and a safe translocation were possible, that Toa himself would be accepted or even survive the process. Balancing the welfare needs of Toa throughout all decision making is an unenviable task. What should remain at the forefront of our actions is his immediate welfare and long-term chance of survival."
Orca Research Trust Founder Dr Ingrid Visser said there were examples overseas where young orca had been successfully reintroduced into the wild.
"We don't know what's going to happen with Toa. But if we don't try, for sure we're going to fail. So we're going to give him every chance that we can to make this work to get him back to his family."
Search efforts across the coast have been aided significantly by hundreds of locals across the Kāpiti Coast down to Wellington's southern coastline.
Te Kawa Robb, one of the co-ordinators of the coastwatching group, said there had often been 20 people at one time in dedicated coastal locations looking for signs of orca.
"It provides reassurance and support for the agencies as well, they know that there are eyes out there, that it's being coordinated in a fashion which hopefully increases the likelihood of a possible sighting", he said.
Members of the coastwatchers group will be looking for orca pods across the coastlines again tomorrow.