Abstract.The semiochemicals carbon dioxide (CO2) and l‐octen‐3‐ol (octenol) were evaluated as attractants at several release rates, alone and in combination, for the major coastal species of biting midges in Georgia:Culicoides furens, C.hollensisandC.melleus(Diptera: Ceratopogonidae). The data show that CO2is an effective attractant for the females of all three species, but each has a different response pattern. In contrast, octenol was an effective attractant only forC.furens, either alone or in combination with CO2; octenol had a repellent effect on the other two species. The combination of octenol and C02had a synergistic effect on the collections ofC.f