Improved estimates of the efficiency of traps for Glossina morsitans morsitans Westwood and G. pallidipes Austen (Diptera: Glossinidae), with a note on the effect of the concentration of accompanying host odour on efficiency

Abstract

AbstractThe efficiencies of five mechanical traps and an electric trap for tsetse flies were measured by estimating the numbers of flies which approached the devices but were not captured by them. With this method, it was possible to discern significant differences in efficiencies even if the means differed by as little as 25%. Three biconical traps had estimated efficiencies of 40–70% for Glossina morsitans morsitans Westw. and 50–80% for G. pallidipes Aust. when used in the presence of the odour of one ox. The efficiency of a small electric net was estimated at 70–75% for all tsetse under this test condition, and a modification of one of the biconical traps had an estimated efficiency of 55–85%. The efficiency of this trap increased by a factor of 1·2–2·2 when used with the odour of six oxen, compared to the efficiency in the absence of host odour. Preliminary results suggested that, when used in the presence of ox odour, the efficiency of this trap for teneral tsetse was at least as high as for mature flies.