Protocalliphora Avium (Diptera) Myiasis in Great Horned Owls, Red-Tailed Hawks, and Swainson's Hawks in North Dakota
Abstract
In Grand Forks County, North Dakota, in 1970-1971, I found the following numbers of nestlings parasitized by Protocalliphora avium (Diptera): Great Horned Owl, 1; Red-tailed Hawk, 34; and Swainson's Hawk, 2. I found cutaneous myiasis in the auditory meatus, nape and neck, axillary area, anal area, and a retrix follicle. Aggregations of eggs in the axillary areas and uniformly-sized larvae in the aural cavities of Red-tailed Hawks suggest that eggs of P. avium were deposited directly upon the host. Larvae remained in the ears of a captive Red-tailed Hawk until they were mature. Nestlings with several sites of infestation were visibly weaker, smaller, and more poorly developed than other nestlings. Sibling attacks on nestling Red-tailed Hawks with heavy infestations of P. avium may result in death.
