They are deadly. "Buffalo gnat" is the name the LA AG center uses but they are also called black flies, bull head gnats, biting flies, turkey gnats and likely many other names based on your region. They don’t Have to to be black like the name suggests, Mississippi State University has an article I am dropping the link here:
They say these gnats may be grey, tan or even greenish in color.
I have battled ants, house type flys from the loquat trees, and fleas expecting each of them to do their annual blow ups. I hadn’t considered that the gnats could be harmful to the animals, I thought the dogs and cats fur and the birds feathers would protect them, just another pest like the others. I knew they bothered me and I couldn’t bring my children outside. I have twin 2 yr olds and a 1 yr old as of this time. On Easter weekend I decided I would treat the yard after the holiday while I was busy getting 100 deviled eggs and a cake ready for the annual family party.
When the deaths started I was convinced I had poisoned my birds. Without the necropsy I would have blamed myself for the rest of my life. Because of that i will always push people to have a necropsy if you are having deaths on your property even if you think you know what it is you better be 100% sure to make it stop, or risk losing a lot of your animals. I pulled every bird from every coop/cage and cleaned everything replacing the bedding, baths, and half the coop litter. I started losing my mind, for a few days they were falling at half a dozen every time I walked outside. I was suposed to be NPIP certified that week. Finally I lost a banty cochin who I had had for years, even through a sellout where I only maintained her and her "sister," it broke my heart, but I knew they hadn't been given the ash I was blaming (as being the “poison” I thought had killed the others.) So I ran off to LSU that day. I secured the hen in a garbage bag for the drive, I did not need to ice or freeze her, it had only been a handful of hours and I am lucky they are only an hour away.
So that’s how I lost 41 of my 42 quail and one bantam cochin in less than a week. I saw them in all stages of these terrible deaths but I didn’t notice the bugs actually ON them, or head shakes, or any swelling. I only saw blood around the eyes and thought that was due to poisoning. I thought lethargy was the buildup of the poison in their bodies lastly before death. I was very busy and I was bothered by the bugs to the degree I started doing my waterers at night after I put the children to bed.
The bugs are NOT active at night. They like open sunny areas although not too hot. Once the temps start to rocket they're suposed to disappear. I think mine survive because there are two nearby bayous (“they breed and live on water") and plenty of places to hide from the heat of the day. Its been in the 90s all week and they're still here. The breeding season is only 4 or 5 weeks then the swarms should die down. They don't fly well so when winds pick up they will disappear and fans can give your outdoor critters some peace. They avoid enclosures and when they ride in on me they fly to the sunny kitchen window and stay there til i can extract some vengeance. Keeping your livestock in barns and coops may help but my experience is that they will go inside coops if chasing a meal.
The AG paper says they attribute stampeding deaths to the gnats such as when a friend said she lost her mare, she bolted and fell and broke her shoulder. Ear infections and irritation are signs of gnat problems in large animals such as horses. Trampling deaths are attributed to gnats too. Two of my friends and an uncle in my area all lost a couple of chickens. I would've probably lost more large fowl if my birds didn't get to free range and escape the swarms. The quail didn't stand a chance small birds in small cages, and very little blood to begin with. This was sudden not ongoing. I made a thread and several people chimed in that they had had problems but more people said they had no idea like myself.
Deet does nothing against them in my experience you need permethrin. It should be kept on hand so you don't find empty shelves (like I did) while everyone in your area is struggling with the same problem. Almost all farm supply stores sell it in a wide array of name brands. Here is an example of what i have:
Light colored clothing helps, a fan as mentioned before definitely helps, vanilla extract mixed with water can help for a short time in a pinch. Skin so soft and supposably dryer sheets help with humans but are untested on livestock so be careful, of course you should always take care when working with your animals anyway.
Even after the initial spraying of the chemical you will need to re-spray after each time it rains and each time the grass is cut. I understand most people hesitate to spray chemicals everywhere over and over but these are pretty safe. Once dried the chickens can go back to eating grass like normal. I have outdoor cats and they're fine but I would not spray them directly. I did spray the dogs though and the birds of course. The directions are pretty clear and easy to follow on the packaging. Please use the products as intended on the directions.
Most of the deaths are caused by toxemia, from the bites and a toxin in their saliva. They can also suffocate an animal swarming them and clogging all passages. My necropsied hen showed gnats inside every bit of her. The gnats also carry diseases. Before death, aside from the lethargy they will suffer from swollen eyes, blood around the eyes after repeated bites, and you can find bites even under the feathers if you part them like a mite check.
I was able to treat the remaining hen who my deceased banty lived with. She was at the lethargic stage already and she was hardly eating feed but she still ate some scrambled eggs so I was able to help her keep her metabolism moving. I gave her nutridrench and as much water as I could get her to take. Took about 4 days for her to shake back to her normal self.
I know this is lengthy, but I felt my story needed to be shared to save other animals and the general heartbreak and frustration of these relentless gnats. If you've read to this point though I hope you've learned something and I'm really glad that at least you are now informed.
Please don't make my mistake, protect your flocks and if you see something here that you question or an error you would like to suggest for editing don't hesitate to contact me. Thank you!
The papers have reported it, see below:
Lastly a link to my own thread where I will continue to document this ordeal:
First pic courtesy of @aart thanks again!