What's Biting Me Now?

The mosquito hordes are gone, but two other bothersome flies have taken their place: deer flies and eye gnats.

Deer flies (Genus Chrysops) are yellowish-brown, with dark wing patches and large, multicolored, metallic eyes. The Genus name means 'shining like gold', and refers to their impressive eyes.

Two different species of deer fly. The gradations are millimeters.

Deer flies are larger than house flies, but smaller than their relatives the horse flies. You'll know them by the deep buzzing noise of their wings, and their habit of rapidly circling your head a few feet away - before closing in for the bite.

The business end of a deer fly, and a view of its colorful eyes.

Unlike mosquitoes which have mouthparts similar to a hypodermic needle, deer flies have cutting mouthparts which slice the skin, causing a painful, stinging bite.

Deer flies prefer warm days and sunny locations. They're common in fields and along roadsides, as well as in forests.

In contrast, eye gnats (Genus Liohippelates) prefer dark and shady locations, especially near water (although this summer, they seem to be everywhere). These chunky flies are very small - only a few millimeters in length.

Several eye gnats. The gradations are millimeters.

Their tiny stature belies their ability to be intensely annoying. As their name implies, eye gnats will head straight for your eyes. They don't actually bite. They simply want to lap at your tears and mucus secretions. Unfortunately, they often dive, kamikaze-style, right into your peepers, getting stuck and causing a sharp, scratchy pain. Imagine someone throwing sand in your eyes.

Large swarms of these tiny terrors can be maddening. In fact, the 'hippelates' portion of the Genus name means 'horse driver', referencing their ability to drive horses crazy. (The prefix 'lio' means 'smooth', and refers to their non-hairy bodies).

Deer flies and eye gnats are especially bothersome, because DEET and other repellents don't work particularly well to deter them. You can protect your head and face with a mosquito-netted hat, while long clothing will protect your arms and legs. These items aren't particularly enjoyable to wear on steamy summer days, however.

Here's a different option that I use. It's pesticide-free, and doesn't require extra clothing, although it does involve a bit more work, and some hand-eye coordination.

A collapsible net with the handle removed.

Purchase a fine-meshed insect net. Amazon has good, inexpensive ones with light aluminum handles that can be taken apart for easy storage.

This one cost me about $10 on Amazon:

Use the net to sweep up bothersome flies as you hike. You'll have to develop quick reflexes - not only to catch the flies, but also to avoid ripping the net on branches, or hitting your companions.

To keep the insects in the net, flip the bag over the front of the net opening after each catch (as shown in the picture above). You can also twist the net around in your hand to close off any escape.

Simply keep gathering the pests throughout the hike. You may even find yourself enjoying the fly hunt!

What to do at the end of the hike when you have a net full of flies? If you're feeling magnanimous, you could invert the net and let the captives go. Or, you could dispatch the flies with some hand smacks or a foot stomp - though this will make a mess in your net. It's better to dispatch the flies in small batches throughout a hike than to wait until the end.

On the other hand, if you have fish, reptiles, amphibians, or chickens, tie a knot in the net so the flies can't escape (or use a few clothespins or a twist tie), bring the net home, and pop it in the freezer for a few minutes. This is one reason why a collapsible net works well - you can take off most of the handle to fit the net in the freezer. After a few minutes, you'll have a delightful frozen snack for your critters.