Dunedin Wildlife Hospital's highest-profile patients are about to be discharged.

The last of the kakapo the facility has been treating will soon be released back into the wild.

Hospital staff and volunteers have helped hand-rear several kakapo chicks this year, including 10 birds which were at risk of contracting the fungal pneumonia aspergillosis.

Yesterday, the four remaining aspergillosis-affected birds were cleared to return to their southern island homes, as were two birds which were admitted for surgery - Queenie, which has recovered from a broken leg, and Esperance, which had brain surgery.

One of the kakapo being hosted at Dunedin Wildlife Hospital, all of which are about to be returned to the wild. Photo: Craig Baxter

''It's been really great for Dunedin to have them,'' hospital trust chairman Steve Walker said.

''It is quite sad to see the back of them, but having them has meant the team has been phenomenally busy at what is meant to be a quiet time of year when they can catch up on administration, as patients numbers are meant to drop.''

Last year there were 147 kakapo in the world, but between 30 and 50 chicks were expected to survive this year's breeding season.

This week marks 18 months since the hospital opened.

It admitted 426 patients in its first year, but it has already treated 400 animals in 2019.

Native birds, reptiles, and marine mammals have all been helped by the hospital's veterinary team.

''Having the kakapo has put a big financial strain on the hospital, as we never expected them and never budgeted for them,'' Mr Walker said.

''But we would always answer a call to help any of our taonga species - that's what we are here for.''

Berths on the hospital's current fundraising venture, a wildlife cruise to Milford Sound, are now on sale.

mike.houlahan@odt.co.nz