By Angus Dalton
Sydneysiders have been warned to expect a spike in spider activity due to warm, wet autumn conditions as the number of funnel-webs captured for production of antivenom falls to dangerously low levels.
There’s often an uptick in sightings of funnel-webs, huntsmen and mouse spiders in late summer and early autumn, and rainfall may help usher the spiders indoors.
Spider keeper Emma Teni of the Australian Reptile Park expects a spike in Sydney funnel-web numbers.Credit: Janie Barrett
“You will notice at this time of year, spider activity is just more abundant,” spider keeper at the Australian Reptile Park Emma Teni said.
There are plenty of bugs about for hunting, and Teni said humidity made it easier for spiders to breathe through their “book lungs”, which need moisture to respire.
The Central Coast wildlife park’s staff are particularly concerned about Sydney funnel-webs, the world’s deadliest spider. Not enough spiders were handed in this summer for milking, putting its antivenom program at risk.
The lack of a steady supply could have “deadly consequences”, the park said in an urgent public appeal for more spider donations.
Teni said the park aims to host a minimum population of 300 funnel-webs that can be milked each week.
“At the moment we only have, I would say, about 130 milkings per week,” she said. “We estimate we need about 217 milkings per week to meet the quota that we require for the antivenom program.”
There’s no current shortage of antivenom, but the treatment has a limited shelf life. The park is hoping to harness the last few months of the funnel-web breeding season, which runs until April, to shore up its milking arsenal with more wild specimens.
Males are used for milking because their bite is six to seven times more toxic than females. But more spiders are always needed because males die within a year of maturing.
Spider keeper Emma Teni milks a funnel web spider for the antivenom program at the Australian Reptile Park.Credit: Janie Barrett
The park urged people to resist killing the spiders and safely capture them instead.
“Grab a smooth jar and a long handled spoon, gently place a jar in front of the spider and encourage it to walk into the jar using the spoon,” Teni said. “[Place] a little bit of moisture, either soil or a wet cotton bud in the jar, and safely secure the lid.”
A network of vets and hospitals act as drop-off points for egg sacs and captured spiders.
Spider milkers use a suction pipette to collect the toxin dripping from donated funnel-web fangs, freeze-dry the venom and send it to CSL Seqirus labs in Melbourne.
Staff there rehydrate the venom, inject it into rabbits and extract resulting antibodies from the animals’ blood to make antivenom.
“That process takes about six to nine months in itself,” Teni said.
Last month, the Australian Museum and Flinders University scientists unveiled a new species of bigger, potentially deadlier funnel-web based on observations made by the park’s former head of spiders, Kane Christensen.
The antivenom produced by the park and CSL treats bites from funnel-webs and other related species such as mouse spiders, which are also more abundant at this time of year.
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