The male bird is suffering from cloacitis, a bacterial infection of the cloaca, colloquially known as "crusty bum syndrome".
The Wildlife Hospital Trust manager Jordana Whyte said cloacitis was an issue in the predator-free sanctuary of Codfish Island-Whenua Hou, which was home to Bravo.
Bravo would normally have gone to Auckland for treatment, but could not because the city was under Alert Level 3.
"We definitely have the capability here, and the vet team has been treating him with antibiotics and pain relief - he is responding very well to it," Ms Whyte said.
"Bravo came in feeling very unwell, he had lost a lot of weight and was really under the weather.
"Now, he has perked right up, put on weight, and is starting to get into mischief overnight - he is doing a lot of climbing, making big messes, and pushing things off shelves.
"The vet nurses are never quite sure what they will find in the morning, after he has been busy during the night."
With most of New Zealand, including Dunedin, under Covid-19 Alert Level 2 restrictions, the four-strong vet team at the wildlife hospital was under pressure, Ms Whyte said.
"Alert Level 2 is our trigger for standing down volunteers and closing the hospital to everyone apart from vet staff.
"So that makes it very tough for the vet teams, who are having to do other tasks like cleaning, while caring for a high-stakes patient like Bravo."
Volunteer input into the Dunedin Wildlife Hospital had been severely affected by Covid-19, with a stand-down of volunteers from March until June, and now the current stand-down.
"It is looking like we will need to call for an influx of volunteers this spring."
Fundraising was also a big issue for the wildlife hospital, with four fundraising events cancelled in recent months, including its street appeal — twice.
"We have identified a significant gap in our budget for the year, so we really need to get more funds in," Ms Whyte said.
The Dunedin Wildlife Hospital has applied to the new Department of Conservation Wildlife Institutions Relief Fund, and was hopeful of a positive response.
