Nickel, Lucy and Lola are three of 125 native wildlife rescued in the past six weeks, putting enormous financial strain on the volunteer organisation.

"The cost of feeding such a large number of animals is beginning to pinch," WIRES Illawarra spokesperson Lyn Collard said.

Ms Collard is asking Illawarra residents to help.

"WIRES survives almost entirely on donations from members of the public and our wonderful carers donate their time free of charge and frequently dip into their own pockets to purchase feed," Ms Collard said.

"However due to the overwhelming number of rescues needing to be fed right now we need help to continue to save these beautiful native animals and birds."

It can take days to up to months to recover and rehabilitate orphaned, injured and abandoned native animals.

Also draining resources is an influx of animals needing care from other parts of NSW rescued from recent bushfires and extreme heat waves.

"As well as our local rescues, we are currently raising 40 orphaned flying fox pups that cost around $80 a day to feed," said Ms Collard.

"The cost of raising orphaned kangaroo and wombat joeys to an age where they can be successfully released back into the wild is almost $600 per joey."

Donations can be made online. Donations over $2 are tax deductible. All donations should mention Illawarra in the notes section.