New Mexico Avian Protection (NMAP) Feather Identification Guide It is very common to find only feathers as remains beneath a power line due to predation, length of elapsed time since the mortality, weather, and other factors. It is impossible to determine the exact cause of death when only feathers are located. It is, however, helpful to identify and report the species of bird encountered. Within this section of the New Mexico Avian Protection Conference materials are color scans of actual feathers from several species of raptors at risk due to electrocution or collision with power lines. Each scan is shown at 100% size, enabling a direct comparison with feathers found in the field. In most instances, the scans include a tail feather and a primary flight feather. In some cases there may also be additional feathers which will show sexual plumage (feather) differences, age differences, or some other unusual feature unique to that species of bird. It is important to note that there is a great size difference between male and female raptors. In some species, females are up to twice as large as males which also results in differences in feather sizes. FALCONS The flight and tail feathers of falcons are generally long and narrow. They are also quite stiff in comparison to feathers of some other raptors. This is an adaptation for a bird which relies upon rapid flight to pursue prey. American Kestrel (Falco sparverius) Female Feathers: The tail of the female American Kestrel is rich rufous (rusty) brown with black barring. The flight feathers are similar in that they are barred brown and black. Male Feathers: The tail of the male American Kestrel is a rich, rufous (rusty) brown with a single, dark brown/black band up to one inch wide at the base of the tail. The flight feathers are dark brown/black with a row of large white spots along the trailing edge of the feather. Prairie Falcon (Falco mexicanus) Feathers (plumage) are alike between males and females. The tail feather is medium brown with faint barring of a darker brown. The flight feathers are a dark brown, barred with large, buff colored marks on the trailing edge of the feather. Peregrine Falcon (Falco peregrinus) Plumage is alike between males and females, although juvenile peregrines are somewhat different in appearance. Tail feathers are dark charcoal gray with, medium gray barring. Flight feathers are similar with medium gray marks on the trailing edge of the feather. BUTEOS (Soaring Hawks) The flight and tail feathers of these species are generally large and rounded. These large raptors are designed for soaring over open spaces while they search for prey, or perch hunting. In general, they
consume rodents, snakes, small mammals, insects and only occasionally, birds. High speed pursuit of prey is not essential. Plumage for all Buteo species is alike for male and female birds. Red-tailed Hawk (Buteo jamaicensis) Tail feathers of the adult Red-tailed Hawk are distinctive and are rarely confused with any other species. These feathers are a rich reddish brown color which may have faint bands of a darker brown throughout. They may also show a variable terminal tail band of black/brown near the tip of the tail. Juveniles do not show the characteristic red tail, but instead had a brown tail with darker brown barring. Flight feathers are dark brown on the leading edge with tri-colored barring on the trailing edge. Each bar has a central dark brown line, bordered on either side with a rufous strip and a pale, buff colored strip between the feather bars. Juveniles also show this pattern on their flight feathers. Swainson's Hawk (Buteo swainsoni) Plumage of tail and flight feathers of the adult and juvenile Swainson's Hawk is alike. Tail feathers are dark charcoal gray with only marginally lighter gray barring. The flight feathers of the Swainson's Hawk are distinctive and are not likely to be confused with other species. They are dark charcoal gray on the front and back of the feather with nearly no barring present. This is the only North American buteo that has dark flight feathers throughout. Ferruginous Hawk (Buteo regalis) Plumage of tail and flight feathers are alike for adults and juveniles. The two-toned tail feathers are pale rufous near the base with much lighter, nearly ivory-colored outer two-thirds of the feathers. No barring is present on these tail feathers. The flight feathers are a medium to light charcoal gray on one side and ivory on the other. Barring generally is not present. EAGLES Flight and tail feathers of North America's two eagle species are significantly larger than any other raptors except Turkey Vultures. Adults are alike in plumage but there are a number of variations among different age classes of juveniles, most of which cannot be covered in this document. Bald Eagle (Halieetus leucocephalus) Tail feathers of the adult Bald Eagle are distinctive. They are ivory in color with only insignificant dark specks near the feather shaft. Flight feathers are uniformly dark brown throughout. Juveniles, however, go through a variety of plumage changes for the first four years of life. Tail and feathers of immature Bald Eagles are quite variable. Golden Eagle (Aquila chrysaetos) Tail and flight feathers of adult Golden Eagles are uniformly dark brown with only very faint barring present on the tail feathers of some individuals. The tail feathers of juvenile Golden Eagles are ivory at the base of the tail with the outer third to one-half being dark chocolate brown. The primary flight feathers of juveniles also show an ivory patch near the center of the feathers.