A few animals that spent the part of winter at the Atlantic Wildlife Institute recovering from injuries and ailments have been returned to their natural environment by staff.

One of those animals, an injured porcupine found in a barn in the Fredericton area, was a Christmas Eve admission,  the institute's Pam Novak told CBC's Shift New Brunswick.

The porcupine had mange, was losing its fur and quills and also had crust formation around its eyes when Novak first saw it.

"Its eyes had sealed shut, it couldn't even see because of all the crustiness but three months later, if you go take a look at that video, you can see there is a little bit of different porcupine, a little different situation and he was happy to be on his way," she said.

Novak says it takes a lot of time to treat a porcupine for mange adding there is still one being treated at the institute that has been there even longer than the one just released.

porcupine with mange

The released porcupine was found suffering from mange. (Facebook)

"What mange does is, it's a microscopic mite and it gets onto the surface of the skin and it just kind of burrows in and it creates these layers of crustiness and a lot of irritation, obviously, with scratching," said Novak.

Mange will also cause dehydration and starvation.

"It's a very miserable condition to have to deal with."

Novak says the animals are treated medically to kill the mites, put on pain medication and tube-fed to help them regain strength.

"Once you get them through the process where the mite is killed off,  [treatment is] to bring the whole body back to a releasable stage."

Novak said the porcupine they released showed all the signs of doing well and when the institute could do no more for the animal, it was time for it to go.

Great horned owl, waxwings also treated

The institute also released a great horned owl that had been treated for a month, a young bird that was mostly doing well in the winter weather.

Great horned owl

A great horned owl is released back into the wild after recovering at the Atlantic Wildlife Institute. (Facebook)

"It just needed some time to regain its energy and flight capabilities," said Novak.

There were also plans to release some Bohemian Waxwings that flew into windows, survived but needed some help recovering.

"They are beautiful winter birds that we just get to see during the winter months," she said, adding they wanted to get the birds released soon because they would be migrating back to their breeding grounds.

Those birds will find their food sources dwindling so it's important they are released to join the rest of the flock, she said.