By Patti Drapala
MSU Ag Communications

MISSISSIPPI STATE -- A sudden outbreak of tiny buffalo gnats has created a costly nuisance in many Mississippi livestock operations, wildlife areas and backyard poultry flocks this spring.

The gnats are members of the blood-sucking insect family Simuliidae. While entomologists describe them as black flies, these insects may be gray, tan or greenish in color. They feed on the blood of humans and animals.

The swarming of these pests can overwhelm some animals, causing them to injure themselves or die after stampeding, trampling or crashing into structures. They also transmit various illnesses such as leucocytozoonosis, a disease of turkeys, geese, ducks and sometimes poultry.

“Buffalo gnats can cause death to poultry and livestock by their nuisance effects alone,” said Jerome Goddard, medical and veterinary medical entomologist with the Mississippi State University Extension Service. “Lately, there have been numerous reports of heavy swarms of buffalo gnats attacking chickens and quail in Wilkinson, Amite, Issaquena and Warren counties.”

Goddard said some of the chicken deaths may have been caused by the birds inhaling these gnats, which clogged their respiratory tracts and caused suffocation.

“Sometimes, wild birds and poultry have died from a toxic shock syndrome from the gnats’ feeding,” he said.

In Mississippi, two species of buffalo gnats are considered pests, the southern buffalo gnat, Cnephia pecurarum, and the turkey gnat, Simuliim meridionale. They are mostly harmless unless populations increase rapidly. Most species of buffalo gnats live in the northern areas of the United States and Canada, where they cause tremendous nuisance problems in springtime, Goddard said.

“Fortunately, buffalo gnats are daytime biters and rarely venture indoors, so people can go inside if the gnats are biting,” Goddard said.

People can use repellents containing DEET on themselves, but these products may need to be applied frequently, he said. Light-colored clothing also may repel the gnats.

“People being tormented by buffalo gnats will be happy to know that the adults live only 3-4 weeks and should go away during our hot Mississippi summer,” Goddard said.

Backyard producers can protect their poultry flocks by providing shelter because the gnats do not like enclosures, he said. They also have a choice of permethrin-based, on-animal products labeled for use on poultry. Some of these products also are labeled for use on livestock.

Individuals whose birds are ill or dying and who are unsure of the cause can submit samples to the Mississippi Poultry Research and Diagnostic Laboratory in Pearl, a facility operated by the MSU College of Veterinary Medicine. Currently, the sample submission fee and basic testing costs for backyard flocks, hobby bird flocks and small growers are being billed to the Mississippi Board of Animal Health.

“We would like to have live birds, if possible,” said Dr. Danny Magee, director of the Poultry Research and Diagnostic Laboratory. “If a bird has not been dead more than 24 hours of being found, the carcass should be double-bagged, put in ice and delivered to the laboratory as soon as possible to preserve the integrity of the specimen. It is important, however, that the carcass not be frozen.”

Magee said a typical submission the laboratory receives is from one to 10 birds.

For more information on buffalo gnats, contact Goddard at (662) 325-2085. For questions about disease transmission in animals, contact the Mississippi Board of Animal Health at (601) 359-1170. For human disease concerns, contact the Mississippi Department of Health at (601) 576-7725. For more information about sample submission to the Poultry Research and Diagnostic Laboratory, call (601) 932-6771.