title: Distribution and seasonal abundance of Cnephia pecuarum (Diptera: Simuliidae) in Arkansas.
abstract: Studies were conducted during 1990-92 to determine the distribution and abundance of the southern buffalo gnat (Cnephia pecuarum) in Arkansas. Field collection of adults near streams throughout Arkansas demonstrated adult occurrence in 24 counties. Abundance studies were conducted by using tent traps baited with dry ice in 3 counties in southeastern Arkansas. In 1990, studies were conducted in Bayou Meto (Ashley County); Seven Devils Swamp (Drew County); and Crocketts Bluff, Bayou Meto, and Little LaGrue Bayou (Arkansas County). During 1991 and 1992, abundance studies were limited to Arkansas County. Results and previous field observations suggest 3 distinct populations in Arkansas (southwestern, southeastern, and central). Seasonal occurrence extended from December to April but varied by location and year. Abundance studies indicated variation in both seasonal occurrence and adult density by year and trap location. Although investigations during 1990-91 showed similar seasonal occurrence trends (peaking in early March), higher adult densities were noted during 1990. In contrast, peak adult density during 1992 occurred in late January. Greatest adult density during the course of these investigations was 7,160 gnats/24 h during 1990 at Crocketts Bluff (Arkansas County). Results suggest that additional studies are warranted to determine the impact of environmental and river factors on seasonal occurrence and abundance of this pest.
authors.affiliation: Herbicide and Insecticide Branch of the Biological and Economic Analysis Division, United States Environmental Protection Agency, Office of Pesticide Programs, Washington, DC 20460, USA.
authors.forename: Donald W
authors.initials: DW
authors.lastname: Atwood
authors.forename: Max V
authors.initials: MV
authors.lastname: Meisch
mesh_terms: D000818:Animals; D001131:Arkansas; D003710:Demography; D011156:Population Density; D012621:Seasons; D012843:Simuliidae