Dispersal and host location of the horn fly

TitleDispersal and host location of the horn fly
Publication TypeJournal Article
Year of Publication1974
AuthorsKinzer H.G, Reeves J.M
JournalEnvironmental Entomology
Date Published1974
Call Number00536
Keywordsarticle, articles, cattle, horn fly, horn fly, insect, horn fly, journal, journals, parasite, horn fly
AbstractHorn fly host location in relation to various environmental factors was investigated. There were no significant differences between the success of newly emerged horn flies and day-old flies in locating hosts, or between males and females of either age. In a variety of weather conditions, horn fly dispersal and subsequent host location appeared to be random with respect to predominant wind direction. Directional movements, however, were influenced by temperature, wind velocity, and humidity. The temperature threshold for host location was cs. 18.3 degrees Celsius, and successful location increased as temperature increased from that level. Host location was more successful at low wind velocities; very few flies successfully located a host at high (10-20 mph) wind velocities. Increased wind velocity was the most important adverse factor affecting upwind orientation, while higher humidity levels appeared to assist host location on the upwind positions. High air temperature was the most important factor aiding host location on animals downwind and crosswind to fly-release points. Higher humidity and wind velocity contributed to lower levels of host location in downwind positions. Flies released in evening (2130 h) and early morning (0330 h) were more successful in host location than those released in daylight hours, i.e., 0930 and 1530 h. Horn flies were able to fly 7.3 miles in a 10-h period to locate a bovine host. There was a strong tendency for both parous and nulliparous flies to transfer from one host to another.