It’s a scene repeated in households around Vancouver Island: The lights are down and you’re preparing for bed, when a hairy, eight-legged creature makes a surprise appearance.
At this time of year, that creature is likely to be a European house spider, experts say.
“[The European house spider] is the one that gets out, cuts across the carpet in front of you and totally freaks you out,” said local arachnologist Rick West, who is also a world expert on tarantulas and has three species named for him, including the Avicularia rickwesti. “Because of their annual cycle, you’re seeing more of them at this time of year.”
That cycle centres around something you’ve probably never thought about: spider sex. The males of the species are sexually maturing right now, West said, and they’re looking for mates.
Royal B.C. Museum research associate Robb Bennett, who holds a PhD in spider taxonomy and systematics, likened it to human behaviour.
“It’s like downtown: During the week, everything is peaceful and quiet. And Saturday night, all of a sudden there’s a bunch of newly matured males or young males looking for receptive females,” said Bennett, who once named a particularly speedy species Apostenus ducati, for the Ducati motorcycle. “Basically, that’s the same thing that happens with the spiders.”
If they’re lucky, he said, they’ll get away without being eaten by the female.
Adding to their visibility is the fact that the spiders are now fully grown, West said. A “good-sized male” will measure about 7.5 centimetres across, including its legs.
Other species also become more visible at this time of year, West said, including hobo spiders and orb spiders — “the ones that make the beautiful, bejewelled webs on a frosty or dewey morning, suspended on power lines or on your rose bushes.”
The European house spider, commonly misidentified as the smaller wolf spider, is among more than 1,000 spider species believed to live in the province. Bennett is nearly halfway through a 10-year volunteer project documenting local species and said they should have 800 species confirmed by the end of the year.
Most species have little to no human contact.
“The vast majority are never or rarely seen by most people, simply because of the habitats and places they live,” West said. “They’re very small and even fully grown are maybe the size of your little fingernail.”
Nine out of 10 have fangs too small to penetrate human skin, he said.
The European house spider may strike fear in the hearts of those who encounter them, but West warns that they add more benefit to a home than harm. While the spider can bite, it does not pose a threat to humans, West said.
“They just shouldn’t be killed, they’re excellent little bio-controls,” he said.
The arachnids help control populations of wood-boring beetles, wasps, hornets, grasshoppers and crickets, as well as flies and mosquitoes.
Instead, he encourages homeowners to grab a tea towel or tissue, scoop the maligned critters up, and toss them out the window to continue their natural lives.
Bennett said the spider invasion usually ends by early October, once the weather becomes wet and cools down.
“I always figure all you’ve got to do is just wait. It’s usually just a month from mid-August to early October, and then they’re gone and nobody sees them again until spring.”
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