Sheep blowfly research. VII. Investigations in the Cape winter-rainfall areas

Abstract

Investigations in the winter-rainfall area were carried out with the object of obtaining a complete picture of the blowfly-sheep-carcase complex. The rainfall is well distributed over the whole year, the climate is mild and humidity is relatively high. Under these conditions sheep are susceptible during all seasons so that Lucilia cuprina causes strikes and breeds almost exclusively on live sheep throughout the year. It did not breed in sheep carcases at any time and only a few L. cuprina were obtained from four small carcases in winter. The sheep carcases produced mainly Chrysomyia chloropyga during the cooler months and C. albiceps and C. marginalis in summer. These flies were not found to strike sheep. The questions of competition between Lucilia and Chrysomyia and of the conditions under which C. chloropyga causes strike are briefly discussed. The latter question merits further investigation.