Venomous Spider Filmed Paralyzing Shrew, Hoisting It Up High and Eating It

Researchers have shared the first ever footage of a false widow spider preying on a shrew, and it is even more disturbing than you think.

The footage was taken by Dawn Sturgess in August 2022 at a house in Chichester in the south of England. In a paper, published in the journal Ecosphere on February 10, Sturgess, who is credited as an author, recounted how the spider wrapped the shrew up in silk and fed on it for three days.

The small shrew, a mole-like mammal, was entangled in the spider's web on the outside of a bedroom window. The shrew was still alive but barely moving as the spider's potent venom was beginning to run its course.

In the video, the spider is seen crawling all over the shrew's dangling body, hoisting it into the rafters by threads of spider silk.

"The spider in the video is a fully grown specimen," research lead John Dunbar, of the University of Galway, told Newsweek. "They can reach 14 millimeters [0.6 inches] body size, excluding leg span, and weigh approximately 0.3 to 0.5 grams. Pygmy shrews can reach 6 cm [2.4 inches] body size and weigh 5g, therefore the shrew was about 10 times larger than the spider.

"Noble false widows have evolved tactics, including strong silk and potent neurotic venom, that allow them to overwhelm small vertebrates [much bigger than themselves]. They produce intricate three-dimensional cobwebs and attach spring-loaded silk strings to surfaces. When a potential prey brushes against these strings, it triggers a 'booby trap' and the prey gets further entangled in the web. Noble false widows can also flick silk at the prey using their back legs to further entangle the prey."

The noble false widow spider is native to Madeira and the Canary Islands but is believed to have traveled to the U.K. as a stowaway on cargo ships in the 1870s, according to the London Natural History Museum. They are now considered an invasive species and a threat to local wildlife. For example, the pygmy shrew, as seen in the video, is a protected species in the U.K. and could be threatened even more by this invasive predator.

"We have previously reported on noble false widows feeding on a lizard in Ireland, and on a bat in the U.K," Dunbar said. "This latest observation adds a new group of mammals to their list of prey and shows for the first time how the spider was lifting their prey so high up the web."

The noble false widow may also threaten populations of native spider species. "We already knew that noble false widows were highly competitive against native spiders, with a venom up to 230 times more potent than some common native spiders," Dunbar said. "Adapting to taking on vertebrate prey adds a new dimension to their invasiveness."

False widows belong to the same biological family as the notorious black widow spider, from which they get their name. "Noble false widows produce a venom similar to the one of black widows," Dunbar said. "It contains very potent neurotoxins that can paralyze small vertebrates within minutes."

Although the venom of a false widow is much less dangerous than that of a black widow, it can still have some nasty side effects. "Victims may experience mild to moderate effects such as pain and swelling," Dunbar said. "In rare, more severe cases, symptoms can include tremors, nausea, sweating and fluctuation in blood pressure. A handful of victims have been hospitalized with debilitating pain or presenting with infections that may have been vectored by the spider during the bite."

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