James R. Philips
Birds of prey host many mites, ranging from harmful to harmless to beneficial species. These mites include feather mites, quill mites, skin and subcutaneous mites and respiratory mites, and they reproduce either on or in the host or in the nest. The mites feed on blood, tissue fluid, skin and feather lipids and debris, keratin, fungi, algae and other mites. The mite fauna of over half the falconiform and strigiform species is completely unknown, but 21 families of mites are associated with falconiforms and 17 families are associated with owls, with nearly 100 total mite species in each case and up to 18 mite species known from an individual raptor species. Healthy-looking raptors without obvious mites may harbor populations of 15,000 feather mites and 4,000 quill mites. Abnormal host transferences can occur with birds in captivity (e.g., crane mites occurring on falcons). Owls tend to have the greatest variety of raptor mites, and both owls and eagles often host large mite populations. Hawks tend to have fewer mites and falcons very few. My website at http://raptormites.babson.edu (VIN editor: Link was not accessible as of 2-10-21) provides a more detailed overview of the varied raptor mites, with photographs and an up-to-date host/parasite species checklist for mites of the Falconiformes and Strigiformes of the world. Zoo veterinarians have the opportunity to examine many of the raptor species whose mite fauna is poorly known or unknown, and to discover many new raptor mite species and host relationships.