Pests, other than little brothers, generally are thought of as insects that harm crops or generally make life miserable. Pesticides (pest killers, that is) thus must represent good, right? Well, not necessarily. What we sometimes forget as we swat at pesky flies or mosquitos is that a lot of insects are not pests—indeed, are vital for our well being. And, unfortunately, pesticides approach life with the bias that the only good insect is a dead insect.
We've learned much in recent years about both pesticides and
insects. Bees have long carried much of the burden of pollination—pollination
vital for the production of foodstuffs. As the introduced Honey Bee is being ravaged by
parasitic mites, we might look to native bees to take over pollination. Except native
species have been hit hard by pesticides, and their number decreases. And most insect
pests have their own predators who succumb as readily to insecticides as do the
pests—and generally seem slower to evolve resistance. The resulting picture is
not pretty—loses of those friendly forces arrayed against pests increasingly
immune to our defenses.
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.
A museum specimen of a dragonfly, one of the useful insect predators. Photograph by A.H. Harris.