One of the hottest summers on record in the Australian state of New South Wales has seen an increase in funnel-web spider activity, with two people bitten by the deadly spiders in the past few weeks.

This comes as authorities say the levels of anti-venom in storage to deal with the attacks is in danger of running out.

The furry funnel-webs are milked for their venom in captivity at the Australian Reptile Park on New South Wales' Central Coast, the only place in the country that undertakes this work.

A ranger from the park, Mick Tate, said on Tuesday, that he is calling for members of the public to face their fears, and while adhering to safety precautions, catch the spiders and hand them in for milking.

"Twenty-sixteen saw the least amount of hand-ins in the park's history, despite good exposure and community awareness," Tate said.

"Should supplies continue to diminish the lifesaving anti-venom program will be in jeopardy."

Funnel-web spiders are known for their highly toxic and fast-acting venom and are native to Australia.