Parasitic Insect Abundance and Microclimate of Gravel Pads and Tundra Within the Prudhoe Bay Oil Field, Alaska, in Relation to use by Caribou, Rangifer tarandus granti

Parasitic insects such as mosquitoes and flies are a bother to caribou during the post-calving period. Observers have indicated that caribou use gravel pads and other oil field surfaces during this season to avoid these insects. Parasitic abundance and weather conditions were monitored on active and inactive gravel drilling pads, and in adjacent tundra, during the 1992 and 1993 calving periods. Inactive pads had lower ambient air temperatures than active pads or the nearby tundra. Both active and inactive had lower abundances of mosquitoes than did the tundra. Abundance was positively linked to temperature and negatively linked to humidity and wind velocity. Caribou were evident on both active and inactive pads during periods of mosquito infestations.