A Fly in the Eye

by Josh Palumbo, Forest Management Coordinator

I welcome you to The Nature Foundation at Wintergreen’s attempt to bring some nature and knowledge into your home. The Nine Minute Naturalist borrows from NPR’s lovely 90-Second Naturalist podcast. Since we all have a bit more time on our hands, the goal is to take something that is happening out in our environment and stimulate your brain for roughly nine minutes. I hope you enjoy!


Sometimes ideas for this blog are hard to come by. After four years of writing about observations in the natural world, I sometimes just struggle to not regurgitate the same information. The theme of this blog hit me like a ton of bricks. It hit me more like a fly right into my eye. This Nine Minute Naturalist will discuss why annoying flies kamikaze right into my eyeball on a regular basis.

I revel in the arrival of spring. Spring ephemerals, migrant birds and a chorus of frogs are just a few parts that make the season unique. The other day I was minding my own business in our lovely forest and I was reminded of a negative of arrival of longer days and warmer weather, annoying insects. Many moments over the years have been spent trying to get small flies out of eyes. One pitiful day in the Adirondacks during the peak of the black fly season, I had to leave work early because of the sheer volume of insects stuck in my eyes. The question is why would a fly choose to spend the last moments of its life in my eyeball?

 

Blackfly swarm

 

The easy answer is that we are walking bait traps. Blackflies, along with many other flying pests, are attracted to carbon dioxide output. They will swarm all around the head due to our exhalations. They are also drawn to warm bodies. As your body temperature rises so does the attractiveness of the target. Wardrobe is also a consideration. Dark colors tend to be a greater attractor of many flying insects. The last aspect that serves to attract blackflies or other blood-feeding insects such as mosquitos is exposed skin. Since skin is most often exposed near out faces, flying insects tend to buzz around your head the most often.

Other gnats such as fruit flies, grass flies and eye gnats are attracted to the moisture in your eyes called latrimal secretions otherwise known as your tears. After each attempt to shoo them away, these pesky gnats will keep attempting to get at the moisture in your eye. This seems to explain the kamikaze nature of some gnats.

 

Blackfly larvae in stream

 

Invariably, a gathering of people in the woods during the buggy times of year will reinforce the fact some people simply attract more bugs than others.  Studies from the 1970’s suggest at least 20% of the population attract many more insects such as mosquitos and ticks. Possible reasons besides the before mentioned attractants could be pregnancy, bacteria naturally living on your skin, your diet, or a host of other theories on why certain insects prefer one person over another.

It seems clear the perfect storm of attraction for annoying flies seems to be a warm body hiking strenuously enough to have increased breathing while wearing dark colored clothing and many exposed body parts. Here are your best practices to avoid the fly in the eye. Choose to hike on a day with a slight to moderate breeze. Flying insects do not navigate wind well. Cover as much skin in light colored clothing as possible. Also consider chemical intervention. Soaking clothes in permethrin is a time-honored tradition that works for to repel pests. Repellents containing DEET applied to a hat will also work well. Do not let your spring be ruined by a fly in the eye!