Urban Legends of the Pest World

I am always amazed that creatures as small as insects can generate such tall tales in the human world. The best part is that the government often gets blamed as the cause of these pest problems. The current infestation of crane fly adults has everyone buzzing. Crane flies like cool damp conditions and this past spring and summer have been ideal. Populations are very large and many homes and lawns have been covered by adult crane flies which emerge and mate during mid September. Cluster fly populations are also high and country homes are experiencing heavier than normal infestations.

The current infestation of crane flies is a good example of a pest legend. The European crane fly was first identified in Canada in the Maritimes in the mid fifties and in B.C. in the sixties, in both instances as a result of accidental introduction. It has since spread from these areas and has been present in Ontario since the early nineties. Now, however, legend has it that the government introduced crane flies to control mosquitoes because of West Nile Virus. They are even referred to as ‘mosquito hawks’. A great story but not true. In fact crane fly adults are here for the proverbial short time but good time as they emerge, mate and die. They do not even feed. Crane fly larvae, referred to as leatherjackets because of their tough skin, can cause problems as they are pests of lawns.

Lady beetles or as they are often called lady bugs or lady bird beetles have also risen to legend status. Loblaws are often blamed as the culprit here. The small numbers sold at the grocery store garden centres somehow giving rise to the tremendous numbers that occur in years of heavy infestation. This is one case where we can pin the blame on the government as the Asian lady beetle has been repeatedly introduced into the U.S. and Canada since the early 1900’s in efforts to control pests such as aphids. Asian lady beetle infestations in Ontario seem to be related to aphid infestations on soybean crops. So far this year, aphid infestations on soybeans are light which may mean fewer lady beetles. If they are to be a problem, they will start showing up on the sunny sides of homes on the first warm days closest to Thanksgiving. Another legend has it that Asian lady beetles were introduced by the government to control purple loose strife. Tall tales for such a small bug.

There is a prevailing legend in Grey-Bruce counties and other areas of the province that the government introduced cluster flies to control caterpillar pests of fruit trees. This is not even possible, as cluster fly larvae parasitize earthworms in the ground. They are shown to have been introduced into North America in the late 1800’s in infested earth worms present in dirt used to preserve root crops brought over on sailing ships. Lady beetles are also now being credited with controlling cluster flies. Again, the life cycle of these two insects would make this impossible but the legend continues.

These are just a few of the ‘urban legends of the pest world’. There are many more and they keep springing up as new, introduced pests arrive. Check out my web site at http://www.drbug.ca for the real facts on some of these pests.

Advertisements