BugBytes: Time to squash a few common spider myths

The other day, a funny thing happened on the way to kitchen. I walked past our pet tarantula’s terrarium, prepared to offer my morning greeting—“Hello, handsome”—when I noticed the tank’s lid was missing. Huh.

While not terribly concerned (tarantulas can’t climb glass walls and scamper down slick wood tables, right?), I felt compelled to scan the tank for Ocho, our adopted (and devastatingly handsome) male Chilean rose (Grammostola rosea). According to his Tinder profile, Ocho enjoys slowly cleaning himself, pimping out his Solo-Cup crib with silk sheets and bits of bark, and leisurely daybreak strolls near the water dish.

This morning, however, Ocho was MIA.

Chilean rose tarantulas are harmless to people and are even renowned for their docility. With this in mind, the realization that a large South American spider was currently on a freedom-run through our small North American home was most concerning for the following reasons:

1) We would probably have to explain the fugitive spider to the tile guy, who had just walked in the door to start work, and

2) We are roommates with a fearless (and villainous) Pomeranian who’s partial to juicy invertebrates. (During the summer, this dog’s diet consists largely of the dragonflies and grasshoppers he snags on trail walks.)

I feared that, despite Ocho’s bulk, impressive fangs and ability to flick barbed, urticating hairs at his enemies, he was still no match for the tenacious and meddlesome Pom.

I needed to find the errant arachnid, and quick. But I’d require help. Time to tell hubby.

“Honey,” I whispered as he came out of the kitchen, “something bad’s happened…”

“Oh, God, what?”

“Ocho’s, uh, well, he’s escaped,” I said, tentatively, aware of my husband’s irrational fear that any invertebrate kept as a pet in our house will inevitably “end up in his mouth.”

“Oh, come on! I knew it! I knew that thing would end up in my mouth!”

“He’s probably nearby, we just need to find him and, maybe, not tell the tile guy until we do.” (I imagined Ocho wandering innocently through the under-construction bathroom until the tile guy spotted him, at which point the shower would undergo a second demolition as hammer blows rained down upon the oblivious arachnid.)

After mentally thumbing through (and abandoning) the fantastic—“He’s in the vent system,” “He’s in the dog,” “He’s in my mouth”—I hit on the probable: He’s somewhere dark, cozy and accessible, the closest thing to a tarantula burrow within 15 feet of the tank—a shoe.

Calmly, so as not to alert the furry reprobate still snoozing by the door, I flipped and rummaged through boots and searched slippers. My husband looked on gravely, momentarily frozen by thoughts of a hand-sized spider holed up in the heel of his work boot.

With a few pairs (mostly his) left uninspected, I moved to the kitchen to examine the large gap between the stove and the floor, while my husband—unconvinced by the cursory shoe scan—took up where I left off. His efforts were quickly rewarded.

“Holy crap, I found him.”

Ocho, it turns out, is a budding fashionista. The spider’s chosen sanctum? My husband’s Kenneth Cole dress slip-on. The arachnid was so pleased with his new home, in fact, that he refused to come out, leaving us no choice but to put the shoe into the tank and await the spider’s evening excursions.

Granted, finding a tarantula in your footwear is not the spider encounter that most Billings residents are likely to have.

However, as friends and family have pointed out, the human mind has a funny way of transforming even the smallest spider into Shelob, Her Ladyship the Shadow Spider, when the startle factor is involved.

But being uncomfortably surprised by spiders is one thing. Going on to malign an entire group of essentially harmless (and ultimately helpful) animals is another.

Spider-phobes abound, however. According to the National Institute on Mental Health, the fear of spiders ranks third on the list of American’s top phobias, just behind the fears of public speaking and death.

Some phobias I totally get. The fear of clowns? Definitely. Clowns are objectively terrifying. The fear of public speaking? Sure. People can be super mean. But spiders? The public’s aversion to these tiny animals is a source of endless fascination for me precisely because it’s so irrational.

Think about it, write entomologist Stoy Hedges and arachnid researcher Rick Vetter in their excellent “Field Guide for the Management of Urban Spiders”: “People outweigh spiders by 100,000 times, yet, the little eight-legged creature can cause restrictive fear” in these mammalian giants. “It would be equivalent to you coming out of a Tokyo hotel, having Godzilla take one look at you then run screaming back into the ocean.”

However, if conversations with folks last summer are any indication, people have some pretty wacky ideas about our arachnid friends and about Montana’s spiders in particular.

So with snow still flying and cold temps keeping the bugs at bay for a couple more months, this seems a prime time to address several of the more pernicious spider rumors crawling around town.

Spider story No. 1: “Montana totally has wild tarantulas. I saw one at Swords Park. It was huge. It even reared up and tried to eat my face.”

The straight dope: With the exception of pets and exhibit specimens, tarantulas do NOT occur in Montana (nor do any face-eating spiders, for that matter). Indeed, the majority of the country’s 50-plus tarantula species are generally restricted to the southwest or central United States.

True, as climates change, the geographic ranges of certain animals may increase. But at present, the farthest north you are likely to encounter a tarantula (in the U.S.) is southern Colorado.

In most cases, what Montanans identify as “tarantulas” are actually just very large wolf spiders (family Lycosidae). In the Billings area, these arachnid behemoths are usually Carolina wolf spiders (Hogna carolinensis), a widespread Lycosid species that is considered to be the largest in the U.S., with some females reaching three to four inches in length (including the legs)! What’s more, these spiders, when threatened, can strike a tarantula-like threat posture in which the creatures rear up, spread their jaws, raise their front pair of legs and bluff strike at the perceived menace.

Though intimidating, these spiders are harmless to humans and, with their handsome, seemingly brush-painted markings and big, reflective eyes, are a joy to watch. So, if you encounter one in your home, remember: it doesn’t want to be there either and likely wandered in by accident. Most wolf spiders are active ground hunters that need access to the rich buffet of invertebrates only found in the great outdoors.

To them, your floor or carpet is about as interesting as the surface of the moon. So fight those spidercidal instincts (put down the rolled-up magazine) and instead, use the cup trick—1) set a glass over the spider, 2) slide a piece of paper under the glass—to move the little beast outside. Good deed done.

Spider story No. 2: “OMG, my uncle’s dentist’s brother heard about this guy getting bitten by a brown recluse near the Rims. He had to have his leg cut off!”

The straight dope: In my mind, there’s no U.S. spider less deserving of its infamous reputation than the brown recluse. The smelly heaps of recluse-related rumor and hyperbole that accumulate online spread so quickly, they are difficult to sanitize. So let’s stay local and address the above tall tale.

First: calm down. Second: use your brain.

The only truly medically important spiders in Montana are the Western black widow (Latrodectus hesperus) and, possibly, in some areas, the Northern widow (Latrodectus variolus).

Montana DOES NOT have established populations of brown recluse spiders (Loxoceles reclusa). They simply cannot survive here. The climate is too cold and dry. The species’ current established distribution (as opposed to incidental, e.g. “We saw one in North Dakota, crawling out of shipment of Texas lumber”) is centered in the southern Midwest (to the Gulf) and reaches only as far north as southern Iowa and as far west as New Mexico.

And while all known recluse species (genus Loxosceles) have venom containing necrotoxic proteins, only in very rare cases do bites result in whole-body effects or in the “flesh craters” for which the recluse bite is legend.

In fact, it’s estimated that 90 percent of U.S. cases of loxocelism (the medical condition/symptomology associated with recluse bites) fail to produce any remarkable damage, with many bite wounds healing on their own within days or weeks.

So, why all the spider-focused sensationalism? Because, who wants to read (or publish) a spider bite story where nothing happens? But the internet’s lust for gore and hyperbole is nothing new.

No, a more worrisome (and largely under-reported) source of spider-bite hype involves a disturbing trend among medical professionals to pin vague or mysterious skin maladies on spiders like the recluse, even where no such species exist (e.g. states like Montana and Wyoming).

More frustrating still, doctors often make these diagnoses without a physical spider specimen, which is necessary both to correctly confirm a “spider bite” diagnosis and to pin it to any particular species.

Incredibly, in Southern California, research suggests that 80 percent of diagnosed “spider bites” were actually caused by other arthropods such as ticks and assassin bugs. And in more temperate, less-buggy states like Montana, cases of dermonecrosis are most commonly caused by bacterial infections such as methicillin resistant Staphlococcus aureus (or MRSA).

And this shouldn’t really come as a surprise. Remember, all spiders are venomous but very few (something like 2 to 3 percent of the 50,000 known species of spiders) possess venom toxic enough to harm us hulking, big-brained Godzillas.

Bonus information: On the topic of jumping spiders, the subject of Danielle McCracken’s illustration above, you should also know that they stalk and target their prey (using excellent color vision and complex triangulation) through vegetation, which can lead these spiders into people’s insect-rich yards and gardens.

Of all spiders, jumpers seem to have the easiest time endearing themselves to humans, thanks largely to their charismatic, big-eyed faces, their habit of turning to look at people, and their remarkably complex dance moves, which the males use to entice the ladies. Though more curious than aggressive, jumping spiders will bite if roughly handled. Their venom, though, is harmless to humans.

As for brown recluse spiders, seen in the first photo, it is worth pointing out that they are so common within their range that if the arachnids were truly as heinous as their reputation suggests, the whole of the southern and central U.S. would be devoid of people. What’s more, the spiders are also remarkably shy. If I approached the spiders too closely or quickly, the creatures hurried their violined backs into the nearest crack or crevice and would not reemerge until I had backed away a good distance.

And one more photo:

 

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