Date of Award
5-2026
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Forest Resources
Committee Chair/Advisor
Jess Hartshorn
Committee Member
Kier Klepzig
Committee Member
Peter Adler
Abstract
Eye gnats of the genus Liohippelates are bothersome flies of the family Chloropidae. They breed in moist, disturbed, sandy soils that contain organic matter, and have been implicated as vectors of conjunctivitis, bovine mastitis, and yaws. We conducted research into some basic biological and ecological characteristics. Using wild-caught gnats in a temperature-controlled incubator, we found that their activity peaks between 27°C and 41°C. Trapping at different heights above the forest floor in an open-pine savannah, we captured most gnats at 7.5 m off the ground. This may have to do with the attractiveness of the rotten egg lures we used, as affected by air turbulence near the trunk layer compared to the canopy and ground. We also conducted trials of gnat repellents using traps and human volunteers. DEET (N,N-diethyl-m-toluamide) was the most effective repellent, with an average of one gnat recorded per human experiment replicate and 13 gnats captured per trap replicate, compared to a control of 71 per human experiment replicate and 326 per trap replicate. The other repellents that had significantly fewer captures than control in trap-based experiments were No Natz (a blend of essential oils), oil of lemon eucalyptus (an essential oil), picaridin (a synthetic repellent) and Napa Waterless Hand Cleaner (a cleaning product used off-label as a repellent in southern Georgia). This work highlights a lack of specific eye gnat research in open pine ecosystems and associated questions relating to their ecology.
Recommended Citation
Hospach, Leela, "Biology, Ecology and Control of Eye Gnats in an Open Pine Ecosystem" (2026). All Theses. 4774.
https://open.clemson.edu/all_theses/4774