INFLUENCE OF OTHER INSECTS ON PRODUCTION OF HORN FLY, HAEMATOBIA IRRITANS (DIPTERA: MUSCIDAE), FROM CATTLE DUNG IN SOUTH-CENTRAL BRITISH COLUMBIA

Abstract

AbstractThe effect of coprophilic insects on horn fly (Haematobia irritans irritans (L.)) production from cattle dung was measured at Kamloops, B.C. Adult female flies were trapped after oviposition on fresh dung pads during 24-h sample periods. The pads were then either exposed to field insects for 24 h or covered with frames excluding insects for the same period, and removed to a greenhouse where all fauna emerged.Horn fly females did not show a definite diurnal rhythm in oviposition. There was a single peak in adult abundance during the summer. Numbers of progeny produced per female fly from covered pads showed an apparent peak from 0300 to 0600 h while lowest numbers were produced in the early evening. Throughout the summer the progeny production from pads exposed to other insects was uniformly and significantly lower than from covered pads of the same age. Insects chiefly responsible for this suppression are probably the predators Philonthus cruentatus Gmelin, Sphaeridium scarabaeoides (L.), and S. lunatum (F.). Parasites of horn fly and dung-burying beetles (Scarabaeinae) are scarce and so there is still plenty of opportunity for manipulation of horn fly populations by use of other biological agents.