The Department of Conservation says it doesn't have a time limit on how long stranded baby orca Toa will remain in captivity, and instead it is regularly assessing his health.
DoC's manager of marine species Ian Angus told the AM Show that the welfare and health of the orca was "at the centre of its decision making".
And Orca Research Trust founder Dr Ingrid Visser - who is leading Toa's recovery - told the Herald they had no intention of euthanising Toa unless his health started deteriorating.
"We don't euthanase healthy animals," she said. "That's not on our agenda with whale rescue.
"He's healthy, he is alert, he's engaged and we recognise that there are welfare concerns being in this small pool."
The young orca calf has been cared for 24/7 by Visser, DoC staff and volunteers since becoming separated from his mother at Plimmerton on July 11.
"Believe me, of all the people in the world, I am probably one of the strongest anti captivity people but I recognise these issues and we are looking for signs that he is mentally being compromised," Visser said.
Massey University marine biologist Karen Stockin yesterday said a full and frank discussion needed to be had about Toa's future as he was now over a week in captivity.
She believed they only had two options if he became too attached to humans - euthanasia or put him in a purpose-built facility, however there was none in New Zealand.
But Visser said they were making progress with Toa's feeding and he was now using a teat made by Weta Workshop, which he could choose to suck on as opposed to previously being tube fed.
"We are giving him choice. We are asking him if he wants to come in for a feed.
"If he comes up to us in a feeding session and he knows what that looks like now.
"We're doing what's called a recall, so we're asking him to come over if he wants to feed and he's actively engaged in that. It's his choice and if he stops suckling we take him off and we let him swim around and we ask him if he wants to come back in again."
Visser said Toa now appeared to be over his bout of colic after appearing to only have it for a few hours on Monday night.
They had also trained Toa to pee into a cup each morning so they could test his hydration levels.
"They can tell instantly if he's getting enough food or not. We're also doing daily measurements of his girth and will give us an indication as to whether he's losing weight or not."
She said a panel of vets from a variety of backgrounds - all volunteering their time - were involved in his care.
"He's got a team of vets down here 24/7 ... there are animal welfare vets as well."
Visser said they had discussed euthanasia with Doc staff and iwi.
"But our focus is on the fact that he's still healthy and still coping mentally so we want to focus on getting him back to his family."
How long Toa can remain in captivity was a "moving feast at this stage", Visser said.
"And it's going to be governed by him. We are looking to him to direct us in terms of his health parameters and his mental welfare.
"If he starts deteriorating we have to start having some conversations. Is it a deterioration we can treat? Has he got a cold or has he got pneumonia?
"You can treat a cold in us, like humans and in them, a lot easier than you can treat pneumonia."
Visser said they wanted to get him back in the ocean as soon as possible and they had "all sorts of scenarios going on with relocations at the moment".
"What boats where, can we put him on a trailer to get him up to that boat, can we put him alongside if his family turns up in the bay here, can we get him alongside a boat in a special modified sling that we can swim out to the family."
In a midday update, DoC said moving Toa out of the sea pen today was "unlikely".
Some injuries sustained during the stranding were healing well, "but others require ongoing monitoring", they tweeted via Project Jonah today.
'We have contingency plans for all scenarios'
DoC's Ian Angus said they had been listening to expert commentary nationally and internationally, including that of Stockin, but they were constantly monitoring his behaviour and doing wellbeing and health assessments, including how often he breathed and his swimming behaviour.
Angus said after discovering he had colic they had adjusted his food and he appeared to be doing better.
"Given the stress he's been through we might get that wrong. Yes, he had colic, it gave us a fright but last night the feeding went better."
DoC initially believed he was 4 to 6 months old but now believed he was around 2 months.
"There's been some debate about age. We know we've got a young orca."
As to whether he could die in captivity and if euthanasia was an option, Angus said the best case scenario was that "we will have a healthy orca calf that we can relocate to the pod".
However, they still needed to find that pod.
"The orca has been in a fair bit of trauma. We also have to plan for deterioration. At the moment we have contingency plans for all scenarios. We want to be optimistic but also, we have to be realistic."
As to how long Toa should remain in the small swimming pool, Angus said the expert advice they'd received had varied widely.
"We've had advice that 2 to 3 days [is] the longest; some say 30 days.
"We haven't set a time limit. We're going through a methodical assessment on a daily basis. What we're doing is in the best interests of the orca and if it's not we would have to make some tough decisions.
"The orca is young, it needs to be fed at the moment, ideally by his mother. It's very likely it would perish if it was set free."
They believed Toa was fit enough to be relocated now but it had to be done safely but also humanely.
Given his age, there were basically only two options left for him - euthanasia or putting him into a purpose-built facility of which there was none in New Zealand.