An invasive spider in the UK caught two bats in its web, and only one bat survived the horrific encounter, thanks to the help of a local who freed the entangled creature before it met its demise.
The Noble False Widow spider (Steatoda nobilis) is native to the Madeira Archipelago and the Canary Islands in the North Atlantic, but the species is now found in other parts of Europe, as well as Asia and the Americas. The black widow look-alike reached southern England in 1879 and has since spread to Scotland and to Wales and Ireland, according to a statement (opens in new tab).
Ahead of a new case report, published Feb. 21 in the journal Ecosphere (opens in new tab)no spider in the Steatoda gender was ever observed preying on bats – or any mammal for that matter. But last July, Ben Waddams, a wildlife artist from Shropshire, England, took photos of several bats trapped in a S. nobilis web at his house.
Related: Ewww! Photos of bat-eating spiders
He shared the snapshots on social media, where they quickly caught the attention of researchers from the National University of Ireland (NUI), Galway, Michel Dugon, head of the Venom Systems Lab at NUI Galway and senior author of the study, said in a video (opens in new tab). “We actually understood very quickly that this was a first,” Dugon said.
“We immediately knew the significance of Ben’s discovery and contacted him to work together to document it in the scientific literature as it furthers our understanding of this species’ capabilities as an invasive species,” first author John Dunbar, a postdoctoral researcher from the Irish Research Council in the Venom Systems Lab, told Live Science in an email.
Based on Waddams’ photos, the team identified the spider as an adult female S. nobilis. The bats that fell victim to the spider trap belonged to a colony that lived in Waddams’ attic, according to the report. The spider had made its web directly below the entrance to the bat colony’s abode, in an area strewn with bat droppings.
In July 2021, Waddams saw a dead bat pup hanging in this opportunistically placed web, its wings fastened tightly against its silk-wrapped body. The rear end of the young bat appeared purple and shriveled, suggesting the spider had eaten the animal, the researchers observed.
the poison of S. nobilis is a potent neurotoxin containing some of the same toxins as true .’s venom black widows (Latrodectus); Previous research found that the spiders use this venom to immobilize and feed small vertebrates, including lizards, the authors noted in their report.
“Valice widow spiders, like their closest relatives black widow spiders, have extraordinary prey capture techniques and a remarkably potent venom, allowing them to capture small vertebrate prey many times larger than the spider itself with surprising ease,” study co-author Aiste Vitkauskaite, a researcher at the Venom Systems Lab, in the statement.
“In addition to delivering a bite that injects potent neurotoxic venom, the noble false widow can use other strategies to help subdue prey,” such as hurling sticky silk at them, Dunbar told Live Science in an email. And for large prey, “the spider will attach additional pre-tensioned wires to the prey, allowing the spider to effectively hoist the prey off the ground,” he said.
The remains of the baby bat’s body fell to the ground the next day, but by then an adult bat had become entangled in the same web, Waddams noted. In this case, the bat was alive and not yet wrapped in silk when he observed the animal, so he scooped the bat from the web and placed it on the adjacent wall. The rescued animal then crawled back to its sleeping place.
The researchers identified the bats as common pipistrelle bats (Pipistrellus pipistrellus) or soprano pipistrelle (Pipistrellus pygmaeus), two small, superficially indistinguishable bat species native to Great Britain.
Pygmy bats are protected under the Wildlife and Countryside Act and the Conservation of Habitats and Species Regulations, according to the statement. This means that people could be fined or jailed if they catch, injure or kill the bats, or if they damage or obstruct access to their breeding or roosting sites, for example. according to Natural England and Department for Environment, Food & Rural Affairs (opens in new tab).
“This study presents yet another example of the noble false widow spider’s invasive impact on native species,” Dunbar said in the statement. In a previous study, published in 2018 in the journal Biology and Environment: Proceedings of the Royal Irish Academy (opens in new tab)the team reported that the spider also hunts the viviparous lizard (zootoca vivipara), a protected species in Ireland.
“We know they are much more competitive than native spiders, and this further confirms their impact on prey species,” Dunbar said.
Species of bat-eating spiders have been identified on every continent except Antarctica, and the arachnids usually prey on small or young insect-eating bats unfortunate enough to get caught in their webs, Live Science previously reported. utilities, S. nobilis joins the list of spiders that pose a threat to the fluffy, flying mammals.
Editor’s Note: This article was updated on March 7, 2021 to include additional quotes from John Dunbar. The original story was posted on March 3.
Originally published on Live Science.