The day Alison Taylor's husband came home and found a pelican in his bathroom, he knew his wife's passion for caring for wildlife had moved to a whole new level.

Key points: The RSPCA says many wildlife carers opt out due to the stress and the cost

The RSPCA says many wildlife carers opt out due to the stress and the cost The Queensland Wildlife Hospital in Brisbane is one of the busiest facilities of its type in the world

The Queensland Wildlife Hospital in Brisbane is one of the busiest facilities of its type in the world Governments are being urged to cover the costs of caring for sick and injured wildlife

About a year ago, Ms Taylor joined the Australian Seabird Rescue group on the New South Wales central coast as a wildlife carer.

She has since nursed four pelicans to good health and released them back into the wild, including her latest charge.

Ms Taylor said Diego the pelican was snappy and cranky, but highly protective of her.

"I love them, they've all got different personalities and this one I think has the best personality of all of them," she said.

"This one will sit on my lap and if anyone comes near us he'll snap at them — but he won't snap at me.

"I don't know if he recognises me as his food source, but I just think it's hilarious."

Ms Taylor is one of thousands of wildlife carers registered across Australia, although their ranks are dwindling, leading to a desperate shortage of carers, and wildlife hospitals that are overrun with patients.

Wildlife carer 'burnout'

An injured koala joey being treated at the RSPCA's busy Wacol hospital. ( Supplied: RSPCA Queensland )

Queensland Wildlife Hospital at Wacol in western Brisbane is one of the world's busiest wildlife hospitals, according to Sheila Collecott from Animal Focus at RSPCA Queensland.

Set up in 2012 by RSPCA Queensland, the Wacol facility cares for sick and injured wild animals and is supported by a network of rescuers, licensed carers and vets.

Last year, the hospital was expecting to care for 10,000 animals, but by the end of the year it had cared for almost 21,000.

"I don't know of any other hospital in the world that is taking in more animals than that," Ms Collecott said.

She said if the demand continued, the Wacol service would soon reach breaking point.

"At some point, something has to give ... this is a great concern," she said.

"We are asking ourselves the question every day, how we are going to cope with the ever increasing demand.

"We've outgrown our hospital and we have to look at how we are going to cope in the future."

Ms Collecott said wildlife carers had been opting out because of the stress, the cost and the demands involved in caring for the increasing number of wild animals needing treatment.

"There is a high rate of burnout for wildlife carers because of the sheer volume of animals that they're caring for," she said.

"We've got a lot of older carers that are retiring or bowing out because the cost of caring for the animals is worn by the carer.

"I think unfortunately people are having to sacrifice their caring role to make ends meet."

'Governments need to cover carer costs'

Ms Collecott blames urban growth and development for the huge increase in injured wildlife in south-east Queensland.

Annette Bird said it was hard to find carers for reptiles, particularly the deadly ones. ( Supplied: Annette Bird )

She said it was time for governments across Australia to step up and help.

"These are crown animals, the government technically owns the wildlife, it's not like a cat or a dog that has an owner," she said.

"So we're pushing back to the (State) Government and saying, if we're going to take care of these animals, you need to help us with cost and the cost of wildlife carers."

The RSPCA said it cost $3.3 million a year to run the Queensland Wildlife Hospital.

The Queensland Government annually contributes $500,000 to its operation, with the remainder funded by donations.

The Federal Government pledged $1 million during the recent election campaign and the RSPCA's Mark Townend has this week written to the Federal Environment Minister Sussan Ley in an effort to secure that funding.

Ms Collecott said it was also time for a review of how wildlife carers got their permits.

"There needs to be more regulation and checks and balances on wildlife carers.

"In Australia people can get a permit (to care for wildlife) through membership of wildlife groups, so the Government loses the ability to track who has permits.

"The whole system needs to be looked at so carers get the support that they need to care for the huge numbers of animals that are coming in."

An injured kangaroo joey, one of the thousands of animals treated each year at the RSPCA's Wacol hospital. ( Supplied: RSPCA Queensland )

Annette Bird has been rescuing wildlife for more than 14 years in south-east Queensland and knows about the pressure of caring for sick animals.

Alison Taylor says it is always hard to say goodbye to her animal patients. ( Supplied: Kylie Wenham )

"Last season I cared for over 40 venomous snakes and that's only one type of animal," she said.

"In total, I had 359 animals come through my house."

Ms Bird, who is president of Reptile Rehabilitation Queensland, said she worried that wildlife died simply because there were too few people willing or able to help.

"There is definitely a shortage of wildlife carers and the situation is bleaker if you care for reptiles — I guess not many people accept the risk that what you are caring for can actually kill you," Ms Bird said.

"The cost to rehabilitate one adult male water dragon for one year equates to around $680 ... I should never have done that costing.

"I would have paid my house off years ago if I didn't do what I do, but I wouldn't have it any other way.

"We need more resources to help animals in need ... the funding opportunities for carers are a joke."

Diego, the bathtub-loving pelican, would be released back into the wild in the coming days.

Ms Taylor said saying goodbye to her patients was always a bittersweet moment.

"I get a little bit sad when I let them go but also really excited that they're ready to go back in the wild," she said.

"The last female I had, when I released her and she took off and did a full circle back over me and it was like she was saying thanks and goodbye.

"That was amazing."