How Dangerous is the Dreaded Black Widow Spider?

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Q. About a month ago I found a large black widow spider under the rim of a pot in which I grow my sage. I have never seen one so big! She escaped into the surrounding shrubs, and we didn't weed that area for weeks, hoping that a bird would feast on her while we kept an eye out for a return of her signature web. My husband finally did the weeding, and thankfully he was not bitten. But then I saw another black widow—a smaller one—on a nearby tomato pot. This area is out back, right up against a tobacco field. I suspect that the spiders may have been driven from the field by the pesticides the farmer used this year on the tobacco. (We never found black widows in our back yard before!) I plan to succumb to the temptation to use poison. I'm even willing to sacrifice my edible plants if necessary. Should we call an exterminator? Use household bug spray? Please advise. Our children play in the yard, and we are concerned that someone could get seriously hurt!

---Veronica in Johnson City, TN

A. My instincts—and the statistics on actual widow bites and their aftermath—strongly suggest that living next to a chemically sprayed tobacco field is roughly a billion times more dangerous to your family than having a widow or three eating the pest insects in your garden. Really. Rick Vetter, noted spider researcher at the University of California at Riverside (who explained in a previous Question of the Week why people who think they've been bitten by the dreaded brown recluse spider probably weren't) tells me that he did his thesis on black widows, has worked with the spiders professionally for 30 years, and during that time, knows of only five "credible bites" in his region—"where there are millions of widows". (California is black widow central, he explains.) And nobody died.

"There are just not many bites, despite the spiders being very common," he relates. "It's just not that big of a deal—we're not good prey for them, and the only reason they might bite us is if we grab one or shove our hand into one of their hiding places."

People who are bitten, he explains, will display very distinctive symptoms if they react strongly to the bite. Their stomach muscles will become rigid, other muscles will contract, one limb may sweat profusely, and they may begin 'rocking' to relieve the pain. (Movement actually does act to relieve the pain, he adds, explaining that in one town in Italy they perform a ritual 'spider dance' after a day of harvesting to alleviate the symptoms of any farm workers who might have been bitten out in the fields. Or it might just be an excuse to dance fast and drink a lot.)

If such symptoms should appear (and not just from the arachnophobia many of you are experiencing right now) you should certainly seek medical attention. But the odds are astoundingly against such a thing happening. So relax—and if you see a widow, just spray it with a safe dispatcher of pest insects and arachnids, like horticultural oil or insecticidal soap; there's no need to use nasty chemicals. (This is especially true for our listener next to the Field of Death, who clearly needs no more toxins in her life).

Q. It seems that everywhere I look in my yard there is a black widow spider with the red hour-glass on their underside and messy-looking webs with round tan egg sacks. I found twelve this past Saturday, and that was a normal day of spider hunting. I'm really good about keeping weeds, grass, and standing water under control because I have two small children and am not fond of ticks and mosquitoes. But how can I get rid of these spiders? Normally I just stomp on them, but finding them near my children's toys makes me worried because they're so much deadlier for children than adults. Knowing my boys (ages 2 and 5) they'd pick them up!

---Rachel in Waldorf, MD

A. Sorry, Rache—but if your 'writhing child' scenario were real, we'd have lots of reported cases, public service announcements and widow wipe-out campaigns. Instead, we got bupkiss. The real threats to adults and children are those disease carrying mosquitoes and ticks you are wisely guarding against; and venomous attackers that like to actually USE their venom on people, like fire ants and yellowjackets.

Researcher Vetter says that you DO have the right idea about spider control, however. He suggests that anyone who suspects they have a lot of widows around their landscape first make sure that they are real black widows: black spiders so shiny that they reflect light, half-inch long bodies max, and a red hourglass design on their undersides. If that's what you have and they creep you out, he says to "go out at night with a flashlight and smash them with a shoe or something. They hide during the day, but come out in the open at night to hunt."

In addition, don't disturb the nests of mud dauber wasps; "they are fierce predators of black widows", he explains. And don't leave gardening gloves or boots hanging in outbuildings like a garage or shed where spiders can easily crawl into them; bring such items into the house instead.

And relax, because despite American arachnophobia, the black widow is really just a great predator of flies, crickets and moths—not people. Want more info? Here's a link to the U of C's excellent spider website.

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