The RSPCA has had to close its main Brisbane shelter in Fairfield because of rising floodwaters, forcing the volunteer organisation to plea for foster homes for its animals.

RSPCA spokesman Michael Beatty said many owners around Queensland had been forced to leave their pets behind as floodwaters encroached on their homes.Mr Beatty said the organisation was struggling to deal with the number of animals in their care.

He expects scores of animals to need care as floodwaters hit more homes.

Several shelters have been cut off by floodwaters, with a temporary shelter in operation in Rockhampton.

"We are confident that we can deal [with the animals we have got] but our problem is other animals coming in; we really just can't deal with more impact," he said.

"We don't physically have a shelter to take them in."

Animals in the Fairfield shelter have been given to "trusted foster homes" and a nearby university's vet centre.

Mr Beatty said owners should offload their pets to friends on higher ground as early as possible if they think they might have to evacuate.

"Ideally what they need to do ... is think of the pets first ... and try and get the pet to someone else on higher ground," he said.

Temporary shelters at the Brisbane showgrounds are now allowing people to bring their pets after the local council reversed an earlier order banning animals.

"We managed to convince the council otherwise, thankfully," he said.

Mr Beatty said the RSPCA relied on donations and said the floods would "seriously stretch" an already tight budget.

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