Great Basin Naturalist


Behavior and activity of the rodent bot fly, Cuterebra tenebrosa Coquillett, was studied at a natural aggregation site in central Washington. Daily flight activity extended from 1700 hr to 2030 hr (PDT) beginning in mid-July of 1970 and 1971. The peak of flight activity, in August, was followed by a decline in activity through September. Male flies aggregated on the vertical faces of basalt cliffs, where they awaited females. Daily activity reached a peak at temperatures of 30–35 C. Eggs were laid in rock crevices without regard to the proximity of Neotoma wood rat hosts. Developing fly pupae were found in litter in wood rat tunnels in basalt cliffs.