Recluse Spider Season Is a Myth

This story originally appeared on WIRED en Español and has been translated from Spanish.

Summer arrives, and with it comes an arachnophobic furor—frantic reports about the intrusion of recluse spiders into our homes. Also known as fiddlebacks or violin spiders, these are arachnids of the genus Loxosceles. They’re found in warm areas across the world, including many parts of the USA, and particularly in Mexico, which has the greatest diversity of recluse spiders in the world, with 40 different species.

Headlines declare that the start of May is “recluse spider season,” and that people need to watch out. It’s true that in their fangs these spiders carry a potent venom, which under certain circumstances can be lethal, but really they are elusive creatures that almost always seek to remain unnoticed. We should not get carried away with anti-fiddleback hysteria, much less replicate it. Such anxiety is unscientific, says Diego Barrales Alcalá, the creator of the arachnid identification platform @Arachno_Cosas. The idea of a supposed season of recluse spiders, promulgated by the media, lacks evidence.

“Fiddlers have become the favorite villain and, unfortunately, according to what I have seen, the problem is cyclical. Every so often the ‘season’ arrives. But not of fiddlers, but of fake news,” Barrales Alcalá says. The activity of these arachnids doesn’t vary according to the time of the year, he says. And in his native Mexico, what limited statistics there are on bites certainly don’t add up to the concern seen in the media.

Geographic coverage of human-spider encounters, 2010 and 2020, based on 5,000+ news articles from 81 countries, published in Nature. In blue, encounters with fiddler spiders; in orange, bites; in red, fatal bites.Illustration: Nature

While recluse spiders choose to inhabit our homes, they are not aggressive. Usually they live away from people, in cellars and uncrowded areas of the house. Bites, when they do happen, occur typically when there’s unintentional contact between humans and spiders or due to people deliberately trying to manipulate them.