Many a Northwest hiker has innocently flicked a hobo spider from the inside of a tent. No harm done, at least to the hiker, which is good news because, unbeknownst to many, the hobo — also known as the northwestern brown spider (Tegenaria agrestis) — has been implicated in several deaths.
This import from Europe is fond of woodpiles and forest debris. Hobos are brown with gray markings and eight conspicuously hairy legs with a span of 1 to 11?2 inches. A herringbone pattern in brown, gray, and tan often appears on the abdomen.
Bites are rare and usually occur when the spider is trapped against the skin of an unsuspecting human and can’t escape. Laboratory tests have shown that the female’s bite is far more toxic than the male’s, but that’s of little consequence when you’ve just been bitten. A blister usually results, as can headaches, muscle weakness, visual impairment, and/or disorientation. Some experts say that up to 5 percent of the humans who are bitten by the hobo spider die because they aren’t aware that they’ve encountered a toxic spider.
There’s no specific first-aid treatment. If you think a hobo has bitten you, try to capture the spider for a positive ID. Then head to the nearest doctor’s office.