Like Moths to a Black Light
Last week I set up a light trap in my backyard with only limited success. Then I tried it with black compact fluorescent lights rather than Coleman lanterns. The old gas lanterns give off a great deal of heat and frequencies in the lower end of the spectrum but not much in the high end.
In his research, Karl Von Frisch noted that bees couldn't discern between red (low frequency) light and black paper, while they can see farther into the ultraviolet than we can. It is not much of a stretch to figure that other species might be more attracted to higher energy light. I substituted three black light CFLs for the lanterns. It made a significant difference.
Where I had seen about three to five insects attracted to the lanterns each night, now I attracted 30 or more from several different orders, not to mention species. For example, in the past I've posted photos of caddisfly larvae, but had no adult forms to include. Several came to my lights last night. The green "pale beauty" (Campaea perlata) and its tan cousin the omnivorous looper (Subulodes aegrotata) have put in appearances.
Still, I remember many more insects that came to the Coleman lanterns when I was a kid. Sadly, back then I did not have any black lights. I will probably be running these lights every night until the weather gets too wet. I am still hoping for a giant waterbug, giant cranefly or a ceanothus moth.
The black lights of my "light trap" don't make for a regular trap; the insects are free to come and go as they please. That's the trick, though — the lights are irresistible.
Moths, of course, come by the dozens, but there are others. An opportunistic praying mantis seeks an easy dinner. A burying beetle shows up and a really big California prionus (Prionus californicus). And this time of year, the termites.
These are the flying reproductives on their nuptial flight. Their script, dictated by millions of years of evolution is this: Leave the nest, fly, drop to the ground, meet up, shed wings and seek a crevice in the ground to found a new dynasty. But they are drawn like sailors to a siren's song, although it's not the lights that will kill them, but the bats.
In flight, the termites are clumsy, fluttering creatures, unlike the swift, agile, mammalian hunters, who have learned over the last few weeks that the place where I set up my trap is a target-rich environment. So, early in the evening, the termites come, followed all too swiftly by the little brown bats and maybe others. It is a slaughter. By the time the "flutter mice" leave, there might be one or two termites that aren't flying, but hugging the fabric.
If you're quick, you might get a glimpse of the hunter. Photographing them is a different matter altogether. They are so small and quick, my best camera can't pick them up, autofocus, adjust light levels, initiate exposure and initiate flash before they're gone. Yet they aren't big enough to trigger my game camera. So I set the focus to manual, pick a likely spot and wait. I rarely guess right, and my reflexes are seldom good enough to get a shot. Usually what I get is a dark photo of the forest around me but, once in a rare while, I get it right. And that makes me grin in the darkness.