Fleas: Siphonaptera

About 5 percent of all flea species occur on birds, while the remaining 95 percent parasitize, or live off of, mammals. They usually do not parasitize amphibians and reptiles. Fleas parasitize hosts in nearly all habitats where their hosts live and are found not only on their bodies but also in their burrows and nests. Bird fleas only parasitize species that reuse their nests year after year, including swallows, seabirds, some ground-dwelling species, and those living in tree holes and cavities. A few flea species that live in coastal, warm and moist, and tropical regions are free-living. Cat, dog, and human fleas all regularly spend time away from their hosts and are commonly found on the floors of homes, foot paths, animal pens, and pet beds. Most larvae are free-living and do not make their home on the body of a bird or mammal. They are usually found in pet beds and nests.