Things you can do with a black light:
- Detect counterfeit bills and semen stains.
- Stage a psychedelic '60s party with Jimi Hendrix posters.
- Kill insects.
Or, in my case, look for scorpions on a balmy desert night. During the day in this part of the desert, I've seen bighorn sheep, palm oases and curious human artifacts. But until last night, I'd never seen a scorpion, although surely they've seen (or, more likely, felt me).
Night is best for scorpion hunting because chemicals in their exoskeletons fluoresce under UV light. If they're camouflaged by day, they're little beacons of blue-green wonder under the illumination of black light at night.
No one knows why scorpions glow in the dark. But nature, of course, does nothing without a reason, even if we don't know what it is. Some people believe that scorpion fluorescence protects against sunlight, like arachnid sunscreen. Some people believe their special glow confounds predators and/or attracts mates.
One scientist, according to Discover magazine, is focused on scorpions' poor eyesight -- unlike humans, scorpions apparently have only one kind of light-detecting pigment, and it's blue-green. They're known to convert the dim UV light from celestial sources into this spectrum of light, so, the theory goes, when their whole body glows under UV enhancement, it might be sending stronger signals to their tiny little brains, rendering, sort of, their whole body as a big eye.
Of the 50-some species of scorpions in California, the casual hiker is most likely to find a desert hairy scorpion, which tops out at about 5 inches, or a California common scorpion, which is a few inches smaller. I don't know which variety posed for me last night, but of all the 10 or so individuals I saw, none was larger than about an inch and a half, and they weren't divulging their ages.
During the day, the desert-colored creatures blend into the landscape, and they want to meet you about as much as you want to meet an e-coli bacterium. Unless you put your hand or foot where you can't see -- always a bad idea when you're hiking or climbing -- you're not likely to see one.
Like other venomous residents, scorpions can regulate the amount of toxin they release to the size of their prey. Unless you're stung by a bark scorpion, the most dangerous local species, you're not likely to suffer more than pain if a scorpion stings you. But like bee venom, some people are allergic to scorpion venom, and pain is the least of their worries.
To meet desert scorpions on your terms, go under cover of night. I was armed with a black-light flashlight provided by Friends of the Desert Mountains, my hiking host. We moseyed along the flat, brushy wash leading to the Art Smith Trail in the Coachella Valley, sweeping our torches along the ground to illuminate the base of creosote and brittlebush, and the nooks and crannies of rock piles.
Lots of things can be mean to people trekking through the desert, but most of them are animate beings that, like scorpions, prefer to make themselves scarce while you remain oblivious. At night, your biggest threat isn't a critter, it's a cactus, or a thorny mesquite. Do not remain oblivious to these natives.
A lot of stuff out here pops under the glare of a black-light flashlight, and most of it is human trash. The desert is a wonder, and too many jerks consider it a dump. Who wouldn't rather espy a fashion-colored scorpion nestled among the dry straw than an empty bottle of Fiji water?
Photo: Ellen Alperstein