Spiders seem to be everywhere in your home and garden, but experts say fear not, it's not an infestation, it's just the time of year they're at their most visible.
It’s spider season.
Perhaps you’ve seen them in your sink or noticed droplets of water glistening on the arachnids’ webs.
“About this time of year, we always get calls from newspapers and from TV channels and radio channels. Everyone is concerned there is an infestation,” said Sue Andersen, an animal keeper at the Woodland Park Zoo.
No, there’s not a widespread infestation. In fact, this time of year there actually aren’t any more spiders, said Rod Crawford, the Burke Museum’s spider expert. We only perceive it that way.
“They’re larger and they’re out in the open and they’re in your face,” Crawford said. It just so happens that October, the spookiest month of the year, coincides with the time several prominent spiders are at their biggest.
More people are calling Eastside Exterminators about spiders this year than any year since 2012, said Aileen Eddy, a pest management service professional, who monitors the company’s calls.
“It’s definitely one of the higher years,” she said.
Eddy believes her office is getting more calls this year because of an “influx” of spiders. “Mild winters,” she speculated. Of course, the increase of calls could also be attributed to an increase of newcomers noticing the eight-legged creatures. Or perhaps a series of nice days — when it’s easiest to notice spider webs — prompted extra inquiry.
Two things are happening, Crawford and Andersen say.
Inside, male giant house spiders, also known as Eratigena atrica, have matured and begun to roam. They’re hairy, usually brown spiders that can have a leg span as large as four inches. Sometimes, they crawl into sinks or bathtubs and struggle to get out.
“You don’t see them until the males mature — until the late summer or fall,” Andersen explained. “They’re not looking for water, which is what people think. They are looking for females — a hot date.”
Before you crush the porcelain-bound Romeos, know that they’re harmless and they rid your house of insect pests, Andersen said.
People also tend to notice intricate webs built by orb-weaver spiders this time of year, Crawford said. There are actually more orb weavers living in springtime, just after they’ve hatched. But they are conspicuous now because their bodies and webs are at their largest.
“The cross orb weaver is the one people notice the most. It’s the biggest and it tends to make its webs most in the open,” Crawford said.
The female cross orb weavers, Araneus diadematus, are most noticeable. With a body as large as three-quarters of an inch, they’re about twice the size of their male counterparts, feature a bulbous abdomen often swelling with eggs and a white cross along their backsides. These spiders build foot-wide spiral webs in gardens, between trees, on railings and sometimes near bug-attracting porch lights.
Cross orb weavers would prefer not to live in your home. Nor do they pose a threat outside. In fact, Western Washington has few spiders with problematic venom.
“Around here, I cannot think of any truly medically significant spider,” Andersen said.
This time of year, the cross orb weavers are approaching the twilight of their lives. In September and October, female spiders lay sacks containing between 300 and 900 eggs. They’ll protect the eggs as long as they can, but most will be dead within a month, Crawford said.
For those worried over their presence, know that these spiders are nearly blind.
“Webmaking spiders have such poor vision,” Crawford said. They can detect light, shadows and movement, but can’t see what people look like. “If you walk up to their web and don’t breathe on them … they’re probably not going to be able to detect you.”
In fact, female orb weavers have difficulty recognizing male mates. “Orb weavers all have a web-based courtship,” Crawford explained.
When male spiders approach, “the male transmits a particular pattern of vibrations through the web to signal the female, ‘Hey, I’m not lunch,’ ” he said.
After their business is done, the male spiders attempt a hasty exit, Crawford said. Female orb weavers are known for occasionally eating the male after mating. The males arrive prepared.
“A male orb weaver has a sort of a loose thread attached near the web and to him that he can immediately transfer to and swing away on like Tarzan,” Crawford said.
Only spiders could elevate the fright of a “web-based” blind date.