Outbreak of Black Flies in East Texas
By Truman Lamb
Anderson County Extension Agent-
Many of you may remember during the nineties, we had an outbreak of Black Flies (also known as Turkey Gnats and Buffalo Gnats). This outbreak came during the Emu and Ostrich boom. Millions of dollars of Emu’s, Ostriches and Horses were lost during this time.
It’s important to know Black Flies can be irritating to people and mammals. They are called Black Flies, they can be gray, brown, tan or greenish in color, they have hump like body. Black flies are tiny and are blood sucking flies in the Simuliidae insect family. They breed in moving water such as Streams, Creeks and Rivers.
They can be a real problem in humans, domestic animals, horses, cattle, poultry, sheep, goats, dogs and deer. Back flies are transmitters of pathogens (nematodes protozoans and viruses) that can cause disease. Black fly females have very painful bites and can exhibit nuisance swarms. Large numbers of black flies can cause bird, poultry and livestock death as well as a stamped, trampling of young, structure crashing and tumbling. Suffocation has been reported and blamed for animal deaths by blocking respiratory passages. Excess blood loss can be detrimental to hosts health. Most deaths are caused by toxemia and shock to the actual bites.
Persistent attacks cause unruly host behavior, weight loss, reduced egg and milk production, malnutrition of young animals, dermatitis, epidermal necrosis, impotence, delayed pregnancy and stress related diseases. control measure for livestock tactics are few.
Repellents with permethrin, Ivermectin and ear tags (pour on and spray formulations), white petroleum jelly inside the ears of horses will reduce bites, as well as providing shelter. For chickens, penning chickens in a coop may not be enough, there are a couple products that best come to mind, Insectrin X, a long-lasting livestock and premise spray active ingredient is Permethrin can be sprayed on surface of chicken houses inside and outside. ProZap Insectrin dust, a ready to use dust. Permethrin II Spray and Ravap can used directly on chickens.
For humans Repellents containing Deet have been somewhat effective but may need to be reapplied frequently and wearing light colored clothing may help keep the gnats away.