AN INFESTATION of funnel-web spiders has taken hold of Sydney over the summer holidays and spider experts are warning that climate change and a spate of wet weather are to blame.

Rex Gilroy, who runs Katoomba Rotary Club's dangerous spiders hotline, thinks a long dry period followed by heavy rain and high humidity over the Christmas break has prompted the critters' march on the suburbs.

Up close and frightening ... a female funnel-web spider at the Australian Reptile Park. Credit:Jon Reid

"I think climate change might have something to do with it. This season there's more moisture and coolness and the spiders have been able to breed up," he said.

But the Australian Reptile Park's general manager, Mary Rayner, believes it is too early to tell if climate change is playing a role.