The Weather Notebook: Snow Fleas

Snow Fleas
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For all its hassles and darkness, at least we can count on winter to give us a reprieve from those familiar summertime pests like flies and mosquitoes. But did you know that some insects actually prefer the dead of winter? Hi, I'm Dave Thurlow and this is The Weather Notebook.

Springtails are tiny wingless insects with distinctive heads and a hump-backed appearance. Other than being a nuisance, these unique little creatures pose no threat. University of Kentucky Department of Entomology
Take a walk on a sunny, snow-covered day this winter and you might run across millions of these insects. You'll have to look carefully, though. Try finding a spot where the snow's melted around a patch of leaves or the base of a tree. You might see a sprinkling of black dots, like pepper grains, on the snow. Look more closely and you're likely to find that those black dots are tiny insects called springtails. They're wingless, and only about one-eighth of an inch long.

Springtails live all year round, but they're easier to see against snow cover on a sunny day, when they come out to feast on bits of rotting plant food. Springtails got their name because of the way their hind legs are held in place by small hooks. In order to move, they release the hooks and their legs propel them up like springs. Because of all this hopping around, springtails are sometimes referred to as snow fleas, although they're not directly related to the actual fleas that dogs know and hate.

In some parts of the country, there are other insects that prefer winter to summer, such as stoneflies, winter crane flies, wingless scorpion flies, and several others. These tend to be most active on cloudy days when the temperature hovers just below freezing. Fortunately, the bugs of winter seem to prefer algae and dead leaves over human blood, that's for mosquitoes. So, enjoy winter, while it lasts.

Thanks today go to contributing writer Bob Henson. The Weather Notebook is underwritten by Subaru and the National Science Foundation.