The dispersal of Culicoides mohave was studied near the Salton Sea in the lower desert of southern California. Preliminary observations indicated that host-seeking females were most active immediately after sunset and immediately before sunrise. A mark-release-recapture technique was used to document a mean distance traveled of 1.2 km, in 12 hr (the first flight period) and a cumulative distance of 1.94 km after 30hr (following the second and third flight periods). Nearly 14% of 20,646 marked females were recaptured. Although the mass of the population moved with the prevailing wind, many females dispersed against it, one as far as 6.0 km in 30 hr. Unmarked females were captured at all trapping locations in the Salton Sea basin (up to 4.59 km from the larval habitat), but their numbers diminished precipitously 2.5 km beyond the shoreline.