Eight out of 109 spider species are able to catch and kill fish by ambushing and injecting them with lethal doses of venom

This article is more than 6 years old

This article is more than 6 years old

Spiders that prey on fish by injecting them with lethal doses of venom are far more widespread than previously known, according to a study.

A research paper published in Plos One this week into fish attacks by spiders found eight out of 109 families of spiders around the world have the ability to catch and kill fish.

The most common type of attacks were by nursery web spiders that can “swim, dive and walk on the water's surface”, according to the report, which was written by the University of Basel’s Martin Nyffeler and the University of Western Australia’s Bradley Pusey.



The spiders wait to ambush their prey on the edge of the water’s surface, and attack the fish by injecting them with a lethal dose of venom.



The largest fish reported to have been caught was by a pisaurid spider and was nine centimetres long, in an incident that was witnessed in a garden pool in Sydney.

The highest number of fish attacks by spiders were recorded in North America, with 45 separate fish attacks – but 12 attacks were also recorded in Australia.



“Pond fish were repeatedly caught by spiders in suburban/urban gardens of Adelaide, Brisbane, Lismore and Sydney or native freshwater fish were predated by spiders on the fringes of slow-flowing streams in New South Wales and Queensland,” the report said.



The study examined 89 different reports of spider attacks, some of which were published for the first time.



“Evidence of the extent of fish predation by spiders in laboratory and field experiments suggests it is more widespread than traditionally thought. However, the propensity for spiders to feed on fish and the importance of this trophic relationship under natural conditions remains unclear,” it said.



• This article was amended on 20 June 2014. The earlier version referred to a “legal dose of venom”.