"Nasty gNats"

by Matt Conner, Park Ranger White River NWR

Got Gnats? An all to familiar sight on windshields in Arkansas county.

It is a Saturday afternoon in March and my family and I decide to head to town for our weekly shopping trip. We gather all of our needed supplies and we stand inside the protection of our home as we identify our destination through our kitchen window. “On the count of three we will run out of the house towards the van. We will run to the van, drop the diaper bag in front of the side door, buckle the kids in, and then grab the bag as we jump into the front seats.”
Moments later we make our run for it. Halfway to the van we drop the baby’s blanket and at first I consider it an acceptable loss until I am instructed that we are not leaving without this vital travel companion. Our plan is now foiled as I have to make a return trip for the blanket and back to the van. These precious seconds have allowed dozens of flying predators to infiltrate our vehicular perimeter. As we drive off windows open and swinging the baby’s blanket over our heads to herd these pests out of the car window, I look at my wife and say, “I had no idea buffalo gnats would be this bad.”
Last winter I was talking with a local friend that asked me how I liked Arkansas now that I have been here awhile. “I love it!” I said. “I survived the heat of the summer and the mosquitoes so I think I have seen the worse that Arkansas has to offer.”
There was a long pause and then my friend said, “You haven’t seen the buffalo gnats yet, have you? That might change you mind.”
I gave him a look of doubt and said, “You made that up, there is no such thing as buffalo gnats.” Boy was I wrong. I was told that these gnats get their name from their resemblance to a buffalo with a humped back and stubby looking body. As I heard the description all I could picture was the emblem from a restaurant that I used to go to in Minnesota that had a picture of a buffalo with wings attached to it. This was used as an advertisement for buffalo wings and this image would stay in my mind until I saw my first buffalo gnat in the spring. Well, I have certainly seen my share of buffalo gnats since then.
It seems these tenacious gnats are the center of most conversations in restaurants and local business as everyone is feeling trapped indoors waiting for these little creatures to go away. I have heard several competing theories as to what brings out the gnats and what determines when they will leave. Still confused, I decided to gather some information and on their biology in hopes of finding a weakness or way to outsmart this winged anomaly. Our biologist Richard provided me with some research and I began my search.
This species is in the order Diptera, which also includes the mosquito. The buffalo gnat has the same set of mouth parts as a mosquito and the female feeds by jabbing its mandible into the skin and uses a second set of blades to cut the skin like scissors until blood begins to flow. The “bug bite” we see after the fact is caused by the anti-coagulating saliva the gnat pumps into the incision to prevent the blood flow from stopping. The female will double her weight during this feeding and will spend two days digesting the meal. After the meal she will lay approximately 400 eggs on the water surface. These eggs will sink and wait 6-8 months before hatching the next year.
The buffalo gnat lives in slow moving streams and rivers whereas the mosquito prefers stagnate water. The buffalo gnat needs moving water because it spends the first part of its life as a larvae feeding by filtering the water that passes by it. The length of time that they stay as larvae is completely dependent on water temperature.
The only factor that stops the larval development and puts an end to the season's buffalo gnats is an increase in water temperature. When the water temperature gets above 66 degrees F, the remaining buffalo gnat larvae in the water die. Most folks think the air temperature is what kills the gnats off, but the gnat populations will decrease first as the small streams and water ways warm up before the larger bodies of water. Once all these waters are above 66 degrees, the gnats are gone until next year.
Sprays and repellants are of little use as gnat will travel several miles looking for habitat. As they travel they feed on livestock, wildlife, pets, and humans. The gnats have killed animals by toxemia from large numbers of bites and blood loss from multiple feedings. Deer have been seen running through open fields trying to avoid the gnats and wading in water and streams to prevent being bitten. In fact, my wife recently hit a deer with our van in the middle of the afternoon as it ran out into the road trying to avoid the unrelenting pests.
After reading this information it looks as if temperature is the only main factor in controlling the gnats, and I do not have the ability to control that. Knowing that sprays and lawn treatments are of little use, I have decided to use some biological controls. I built a large bat house and hung it inside an old hollowed out tree hoping a colony of bats will move into my neighborhood. I know that the bats could never eat every buffalo gnat, but I will still feel better knowing that something is feeding on the gnats that are trying to feed on me.
It has been a couple of months now since I had that first conversation with a friend about buffalo gnats. Now after going through several gallons of windshield washer fluid from gnats hitting my windshield, several cans of ineffective bug spray, and now a new front end and realignment of our van, I have decided that the buffalo gnats are worse than the heat of the summer and the mosquitoes combined. I still love Arkansas but, if there are any other seasonal infestations coming up in the near future, I hope they have more weaknesses than the mighty buffalo gnat.

If you have questions about our web site or about the refuge, contact Larry E. Mallard at whiteriver@fws.gov

For More Information Contact: White River NWR 57 South CC Camp Road P.O. Box 205 St. Charles, AR 72140 Telephone: 870-282-8200 Fax: 870-282-8234