By Jack Ewing
Most people don’t like bugs. The term brings up negative images of all sorts of undesirable things, both living and not. If there’s a bug in your computer program, some obscure little quirk is making your life miserable. “Don’t bug me!” means don’t annoy me. A bug can be a germ, vermin, flaw, wiretap, defect, fault, or problem. It can mean to pester or bother. My thesaurus lists only one synonym with a positive connotation, the word enthusiast. In Spanish, the word for bug, “bicho”, is often used to mean a very undesirable person.
It isn’t any mystery why people don’t like bugs? They crawl on us, bite us, sting us, get into our clothes, our food, and even eat the wood in our homes. They eat our crops our flowers our lawns and most anything we try to grow. They are associated with all kinds of contagious diseases including many that are fatal. It would appear that our dislike of them is clearly justified. But have you ever thought of what would happen if all the bugs were to disappear from the face of the planet? Well known biologist author E. O. Wilson, in his classic work, The Diversity of Life, answers that question:
“So important are insects and other land dwelling arthropods that if all were to disappear, humanity probably could not last more than a few months. Most of the amphibians, reptiles, birds and mammals would crash to extinction about the same time. Next would go the bulk of flowering plants and with them the physical structure of most forests and other terrestrial habitats of the world. The land surface would literally rot. …other complex forms of vegetation would die off, and with them all but a few remnants of the land vertebrates. …The land would return to approximately its condition in early Paleozoic times, covered by mats of recumbent wind-pollinated vegetation, sprinkled with clumps of small trees and bushes here and there, largely devoid of animal life.”
Many people who live in North America and Europe are accustomed to a comparatively sterile, insect-free environment. This always brings to mind an image of my mother — who couldn’t stand a single insect in the same room with her — chasing a fly or a moth around the house with a spray can full of insecticide or a fly swatter. This happened rarely, as her house was tightly sealed against intruders. Living in Costa Rica, especially in the hot, humid lowlands, means learning to coexist with bugs. The climate requires open construction with good ventilation, a building style that is difficult to seal. In this type of breezy environment your fly swatter or insecticide sprays definitely have their limits. Some people resort to regular fumigation as a method of controlling bugs.
My friend Harry can tell you all about fumigation. “You know something Jack?” he queried. “When I think back on it all, the bugs never really bothered us that much. Sure, we had a few roaches and ants, and we had our share of mosquitoes. I mean, I never minded those big, round, hairy spiders that used to hang out in our shower. They seemed to be more scared of me than I of them. Mabel always got out the long-handled broom and knocked down those big golden tinted webs in the corners of the ceiling, but I kind of liked them there. Those long legged spiders never bothered me, and the webs caught lots of mosquitoes. We used to sleep with a mosquito net during the rainy season, but most nights they weren’t so bad. We always kept a bottle of insect repellent around, but didn’t use it much. One bottle would last me and Mabel for a whole rainy season.
“Sometimes a preying mantis would land on the mosquito net while I was reading in bed. I’ll tell you those things are amazing predators. They can catch and gobble up a lot of bugs in one night. Did you ever see those little frogs with suction cups on their toes? A bunch of them liked to hang out in our bathroom. They would sneak in close to the light and snatch mosquitoes with their long sticky tongues. And those little, dark-colored lizards with the red heads, what are they called?”
“Geckos,” I offered.
“Yeah, that’s it, geckos, they were everywhere. Now those were insect eating machines. They would eat anything they could catch.
“We had bats too. They roosted in the ceiling and made scratchy sounds, but every evening they made a couple of sweeps through the house and cleaned out all the bugs. Come to think of it, there was even a bird, some kind of tanager, that ate those black wasps with the nasty sting. Every fall when the birds migrated in from the north, one would go through the house and clean them all out, eat their eggs and destroy their nests. I never could figure out how it kept from getting stung.
“That was before we fumigated. I know what your thinking, Jack. You want to know why we fumigated if we weren’t bothered by insects, right?”
I nodded affirmatively.
Harry continued. “I mean, I don’t like spraying poison all over my house any more than the next guy. I mean look at all the people who die from cancer. There didn’t used to be so many people get cancer. Way back in the early 70s when I was like 30 years old, I didn’t know anyone who had died of cancer, not a single person. Well, let me tell you, the other night me and Mabel was trying to remember how many people we knew who had cancer or had died from it since then. And you know what? There was more than I could count on the fingers of both hands. I don’t know what you think, but I think it comes from all them chemicals in our environment. They get into our food and water and everything else.
“Anyway, let me tell you why we fumigated. It was because we found a termite trail on the wall outside the bedroom. We asked around to find out what to do about it, and everyone told us we had to fumigate. I thought maybe we could just spray the places where we found their trails, but the people we asked said ‘no’ it was best to fumigate the whole house. So we hired one of them companies to come out and fog the place. They told us that the stuff they used was organic and it wouldn’t hurt people, only insects. I didn’t believe it, but that’s what they said. In almost the same breath they said the stuff was so strong it would last three months. After that they fogged the house. We left all the doors and windows closed and stayed at a hotel that night. The next day we opened up the house and moved back in. I didn’t like the smell for a couple of days, but it gradually went away. We had to clean the whole house; sweep out all the dead spiders, moths, frogs, geckos, preying mantises and a couple of cockroaches. I mean the house was free of small animals. Nothing was left alive. We even found two dead bats. The termites were gone for the time being.
“It was amazing. Within a week the cockroaches were back. But not like before when we only had a few. After the fog-down, they were all over the place. I don’t know where they all came from, but they took over the entire house. And mosquitoes like you wouldn’t believe. We had to smear that oily repellent all over us in the evenings and sleep under the mosquito net every night. That was two months ago. It’s a little better now. A few geckos have come back and I saw a frog in the bathroom a couple of nights ago. Mabel found a spider web in the spare bedroom this morning. She said she left it there. I guess that guy from the fumigators was right about that stuff keeping things away for a long time. It sure keeps the insect eaters away. But it don’t do much for them cockroaches. And you know what else? We found another termite trail a couple of days ago.”
Harry went on to tell me that for the second termite invasion, he found an insecticide that was specific for termites, and sprayed it only on the places where their trails appeared. Then he went out and looked for termite nests in the trees around his house. He knocked down all the nests within 50 meters of the house, three of them. He figures that in another month or two populations of all the insect eaters will return to normal. Harry is especially anxious for the geckos to return. He found out that their favorite food is cockroaches.
Several books could be written about the natural enemies of household insect pests, but the geckos deserve special attention. These small lizards, as long as your index finger, don’t bother people, but feed on things that do. Two species, in particular, like to live in homes. Both the orange-headed gecko (Gonatodes albogularis) and the common house gecko (Hemidactylus frenatus,) frequent coastal regions like our own. The underside of a gecko’s feet are covered with thousands of hairs or bristles, each with a special bonding mechanism that works with positive and negative electrical charges. This trait enables the gecko to cling to walls and ceilings. When a rat, bat, bird, snake or cat tries to grab a gecko, the predator ends up with a piece of tail in its mouth. A stinky substance oozes from the tail stub, and the short-tailed gecko promptly scampers away. The lost appendage soon regenerates. At our house they can be found in every nook and cranny. Their favorite food is young cockroaches. We don’t keep any kind of pesticide in the house and seldom see a cockroach.
Large round pupils indicate the diurnal nature of some geckos, like the orange-headed one, whereas a nocturnal species like the common house gecko, has narrow vertical slits as pupils. Geckos’ eyelids don’t move. Fused to the eyelid is a fixed transparent shield that covers and protects the cornea. Rather than blinking, the gecko licks the shield in order to clean it. Whenever I try to imagine this, I remember a joke I once heard about a guy who licked his eyebrows, but you’ll have to turn to the joke page for that.
When you’re enjoying a pleasant evening at home and hear a friendly “chrit-chrit-chrit,” that kind of reminds you of a bird, but not quite; remember the gecko, the only semi-domestic reptile in the world. And you might take a moment to thank them for controlling the bug population in your home so that you can live in a healthy, chemical free environment in harmony with the natural world that surrounds you.