Wild Things: Turkey vulture (Cathartes aura)
The Turkey vulture is a wide-ranging soaring bird, with a wingspan up to 7 feet and body length somewhat less than 3 feet, making them the largest raptors in the U.S. except for eagles. The species is termed a New World vulture due to its distribution across North and South America. It occurs year round from the southern U.S. down through Central and South America, and is found in the breeding season only in a band across the central U.S. and into southern Canada. Turkey vultures are named after turkeys because of the similar naked featherless head. The naked head, red skin with black tinting and with only a smattering of short fuzzy feathers, is a sanitary adaptation to the carrion diet of these birds. Bacteria and other parasites and organisms already feeding on the carcass are less likely to adhere to the bare head of the vulture than if it had a feather covering. The beak is white and the cere (nostril skin) is red.
Turkey vultures have brown backs and tail. The underside of the soaring bird shows a dark body and leading edge on the wings and white feathers along the trailing edge and tips of the wings and tail. While most birds have a poor sense of smell, Turkey vultures are unusual in being able to detect the odors emitted by carrion. Experiments in which carcasses have been covered by leaf litter and were well camouflaged still attracted Turkey vultures. These vultures do not kill their prey but serve the important ecological function of recycling the nutrients in dead animals. They do occasionally take live insects and feed on dying fish that have been stranded in drying ponds.
Turkey vultures often spread their wings in the morning, a behavior that serves to dry and warm the wings for flight and also to allow sun light to penetrate the feathers and diminish bacteria and other parasites on the skin. The photographs taken here of a sunning vulture with spread wings were taken adjacent to N.M. 41 south of Moriarty.
These vultures are soaring birds. They occur in open prairie or shrub land environments near woodlands or in forested mountain areas with open habitats nearby. They are best able to detect food sources in more open habitats but need the vertical structure of forests for roosting and perching. They use very little effort in their flight patterns, effectively using any rising air currents to gain altitude and remain aloft for hours at a time. On hillsides vultures will soar in the ridge lift on the upwind sides, but they are most efficient at working thermal lift. Thermals originate from heated ground and rise to form the familiar cumulous clouds as the thermal temperature decreases with increasing altitude until it reaches the dew point temperature. Turkey vultures soar with the wings tilted up in a V configuration, or with dihedral. They can be distinguished from eagles in flight because eagles soar with the wings level across in profile.
Females lay two eggs in a cliff face nesting site or other bare surface. Both parents will incubate the eggs and feed the nestlings by regurgitation. The young hatch after a month or more and are fed and cared for by the parents for two more months, when they eventually fledge.
The Turkey vulture is protected by the Migratory Bird Treaty Act in the U.S., making it is illegal to take, kill, or possess the birds or their eggs. The Audubon Society predicts that the range of the Turkey vulture will not be greatly affected by continued climatic warming and the species is considered stable at this time.
James Taulman is a semi-retired research wildlife biologist, having worked with the U.S. Forest Service research branch and taught zoology, ecology, and other courses in several university positions. He lives in the East Mountains, and explores natural areas observing native wildlife and conducting independent research projects. Search for James Taulman on Youtube to see wildlife videos.