Want to kill the bugs that bite? Don't use a zapper

August 19, 1998

Dennis ShawBy Dennis Shaw

One of life's more difficult experiences for me is to be a guest at someone's home and keep my mouth shut while they do something I don't approve of.

This happened to me recently when I was invited over for "a picnic dinner out on the deck." This sounded harmless enough, and in most respects, it was. In fact, the food, the weather and the company were nearly perfect.

But alas, throughout the meal, my hosts were engaging in murder.

It was hard not to be aware of it, for every few seconds I'd hear a zapping or popping sound as another innocent victim was electrocuted.


The victims of this massacre were flying insects.

The instrument of death was the electric chair, or in their case, the electronic insect control, or "bug zapper."

This hanging basket with its ultraviolet light bulb was luring unsuspecting insects to its cage and then frying them.

I know I should have been grateful. My hosts were only trying to protect us from mosquito bites. But it was to no avail, for we were still being bitten, and they were talking about buying another zapper, or a bigger one.

At that point I summoned up my courage and mentioned two articles I'd read recently about the pitfalls of bug zappers. According to the articles, the zappers are killing the wrong guys.

The problem is that the zappers do their job on insects that are attracted to light, such as moths. These bugs use a light source either to navigate or to find mates.

But mosquitoes are not attracted to light; they're attracted to us! They can sense our body heat and the carbon dioxide we mammals breathe out, and that tells them there's some fresh blood nearby for the sucking. So they're not usually victims of the zappers.

To make matters worse, many of the insects that are killed by zappers are the kind that eat mosquitoes. So the zappers are killing nature's own version of mosquito control. Many of them, such as bees, also pollinate the crops we eat. An estimated 99 percent of all insects are considered to be either harmless or beneficial to us.

Some students at University of Delaware actually counted and identified the fried bugs under six zappers and found that out of 14,000 bugs, only 31 were biting insects. Dateline NBC did a similar study, and in one night found only eight mosquitoes among 10,000 dead bugs.

I don't think my hosts were convinced when I pointed this out to them.

Especially not when they asked if I had a better idea, and I suggested that they put up a bat house. Bats are supposed to eat a lot of mosquitoes, as many as 500 in an hour, though I can't imagine how anyone ever counted that.

I suspect I might not be invited back for another dinner, anyway.

In addition to my reputation as a tree-hugger, I imagine I'm now being described as a bug-lover.

Guests in my home still look at me strangely when I find a wasp inside, and instead of swatting it I carefully capture it and release it outside.

I do that partly because I don't like to kill anything if I can help it. I also like to think that wasps eat mosquitoes.

And maybe I'm right, because I don't have any mosquitoes around my home. I don't have an electronic bug zapper, either.

Dennis Shaw is a former Herald-Mail editor. Write him at P.O. Box 276, Clear Spring Md. 21722, or call 301-842-3863.

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