Field trials of baits to control populations of Glossina morsitans morsitans Westwood and G. pallidipes Austen (Diptera: Glossinidae)

An island of 4·5 km2 in Lake Kariba, Zimbabwe, was stocked with cattle and infested with Glossina morsitans morsitans Westwood and G. pallidipes Austen in 1979. From February 1980 to April 1981, the tsetse populations, estimated by mark, release and recapture, increased about ten times, to contain about 3000 males of G. m. morsitans and 2000 males of G. pallidipes. From May 1981 to May 1983, six traps, with carbon dioxide and acetone as odour attractants, were used to capture 0·1–0·3% per day of the G. m. morsitans population and 1–4% per day of the G. pallidipes population. Captured flies were retained and killed, or were automatically sterilized with metepa and released. In May 1983, when the populations of G. m. morsitans and G. pallidipes had declined by about 90 and 99%, respectively, the traps were replaced by 20 targets with acetone and 1-octen-3-ol as attractants. The targets were coated with dieldrin or, later, deltamethrin and killed about 2% per day of G. m. morsitans and 5% per day of G. pallidipes. Both populations then declined rapidly, G. pallidipes disappearing in 11 weeks and G. m. morsitans in nine months. Targets offer a cheap, simple and effective means of eliminating isolated populations of tsetse. © 1986, Cambridge University Press. All rights reserved.