by Whit Gibbons

July 10, 2005

The jury is still out in some minds about whether mosquito eliminators really work, but the concept is straightforward. A propane gas tank stationed below the device is used to generate carbon dioxide and chemical scents that attract mosquitoes away from where people are. Sticky paper or a little fan permanently removes mosquitoes that are lured to the device. The one I tried seems to work. Not having mosquitoes around makes an evening on a deck much more pleasant. The fact that I actually like getting rid of mosquitoes reminds me of a dilemma faced by all ecologists and environmentalists

Every ecologist I know will do whatever is necessary to rid themselves of mosquitoes, flies, fleas, and ticks. So will I. Yet most of us take strong environmental stands about saving endangered species and preserving wildlife. How can ecologists justify protecting venomous snakes, man-eating tigers, and uncivilized rhinoceroses but have a callous attitude toward certain insects?

Full-scale attacks on certain lower life forms are considered acceptable by most people, including ecologists. One ecologist friend of mine who works with horses has a special dislike for horseflies. Most of us take immediate action with intent to kill as soon as a horsefly lands on us, but she strikes before the flies do. She has investigated ways to deal with them around a barn where they are clearly unwanted.

One technique she uses is to suspend a black balloon from a six-foot high tripod. Above the balloon she makes a large funnel of clear plastic with the large end a few inches above the balloon. The small end leads into a plastic three-liter bottle. For some reason, horseflies and deerflies are attracted to the balloon and fly up the funnel and into the bottle. The flies continue trying to escape by flying upward and soon die in the jug. The technique can rid a stable of hundreds of flies in just a few days. Although she is an ecologist and environmentalist, she finds this an acceptable solution to the problem of flies that bite.

What is the distinction between animals we feel should be protected and those that we kill on sight? One difference is that we seem to be in little danger of losing any of the noxious insects. Their replacement capacities seem limitless, so no matter how many mosquitoes one swats in a salt marsh, more will arrive to take their place on your arms and face. Another distinction is that biting insects and ticks attack us and our pets, even in our own homes, without provocation. They find us and invade our privacy. It would be a strange person indeed who would settle for being a meal for another animal. Most people consider these insects as pests with few redeeming qualities to make up for their bad habits. This is of course a totally self-oriented attitude on the part of humans, but this is the way of the world, as run by humans.

Another human attitude that we may be less conscious of is that we protect creatures more closely related to us or that display features we appreciate. Mammals and birds are warm-blooded animals that, like humans, care for their young. A furry or feathered animal, especially if the species is waning in numbers, has our empathy. Likewise, humans appreciate color, and so insects with bright colors or striking patterns are acceptable life forms to us. Few people kill butterflies on purpose.

An additional strike against many flies and mosquitoes is that they do more than get a free meal from us. They can leave a lasting memory in the form of parasites that enter the bloodstream. Even today, malaria is one of the leading causes of death worldwide. Lyme disease from ticks and bubonic plague from fleas have not endeared any of these animals to us either. But, despite all these reasons, I think the key factor is that we know we are not endangering one of these species by swatting it before it bites us. I really would not want to be the person who killed the last pair of horseflies. Would you?

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