Studies on the Reproductive Biology of the Horn Fly, Haematobia irritans (L.) (Diptera : Muscidae) : III. Mating Behavior of the Fly in the Field

The horn fly, Haematobia irritans (L.) was observed to mate only on cow body surfaces especially on the pectoral and cervical regions. Characteristic behavior, such as wing vibration, was not observed before copulation. Mating behavior was observed only during the day, with no discernible rhythmicity of occurrence. In laboratory experiments, the mating percentage of young females increased as rearing temperature rose from 24 to 32°C. Average temperature of copulation site (cow boyd surface) was approximately 30°C and not greatly affected by ambient temperature. Ambient temperature (above 16°C), light intensity (above 2, 800 Ix) and weather affected the mating activity only slightly. The females mated actively at 36 to 54 hr after emergence in the field and at 3 to 7 days after emergence in the laboratory, when terminal follicles in the ovarioles had become occupied mostly by yold protein.