The Red-tailed Hawk is one of the most widespread and recognizable raptors in North America. Known for its distinctive reddish-brown tail, this medium-sized hawk can be found soaring over open country throughout much of the continent. But what about the color of a Red-tailed Hawk’s head? Let’s take a closer look at the plumage of this iconic bird of prey.
Adult Red-tailed Hawk Head Color
The head of an adult Red-tailed Hawk is primarily brown, with some white and reddish-brown markings. The crown and nape feathers are dark brown, sometimes with a rufous tint. There is a variable amount of white mottling on the throat and neck. The supercilium, or “eyebrow”, is whitish, contrasts against the brown ear coverts behind the eye. The cheeks are also whitish with variable brown streaks. The beak is dark grayish blue and the eyes are brown.
So in summary, the predominant head color of an adult Red-tailed Hawk is brown, with white markings on the throat, neck, supercilium, and cheeks. The reddish-brown coloration for which this species is named comes from the tail, not the head.
Changes with Age
The head color of Red-tailed Hawks changes somewhat as they mature. Hatchlings and nestling Red-tailed Hawks have white and gray down feathers on their heads. As they grow their first true feathers, juvenile Red-tails have browner heads with more streaking on the belly and chest. The whitish supercilium and mottled neck become more prominent as they near adulthood.
After the first year molt, immature Red-tailed Hawks have a head color pattern close to adults, but their feathers retain some brown spotting. As they molt each year, the head coloration increases in contrast, with solidly brown crowns and whiter throats. By four to five years of age, most Red-tails have the definitive head pattern of brown crowns and white to buff mottled necks. However, there is much individual variation even among mature hawks.
Regional Variation
While the basic head pattern remains the same, Red-tailed Hawks show regional differences in shade and contrast across their vast range. In general, western Red-tailed Hawks have paler, more whitish heads compared to their eastern counterparts. The Harlan’s Hawk, a subspecies found in Alaska and western Canada, has a very pale gray head with fine darker streaks. At the other end of the spectrum, the southern subspecies known as the Fuertes’ Red-tailed Hawk has a darker brown head with rufous tinge.
There can be much local variation in Red-tailed Hawk head color, reflecting the diversity of habitats and prey across the continent. Even within the same region, some individuals will have darker or lighter crowns independent of their age or subspecies. Keeping in mind their variability, the predominantly brownish head with white markings is a consistent field mark for identifying Red-tailed Hawks.
Diet Influences Color
One factor that may account for regional and individual variation in Red-tailed Hawk head color is diet. Red-tailed Hawks feed opportunistically on small mammals, birds, reptiles, and amphibians. The types and quantities of carotenoid pigments obtained from prey may be deposited in growing feathers, influencing coloration.
For example, ferruginous hawk nestlings fed carotenoid-rich diets of ground squirrels grew feathers with more rufous tint. The availability of different prey across the Red-tailed Hawk’s range and individual hunting habits likely contribute to color variability. What a hawk eats as feathers are grown may leave a signature in its plumage.
Significance of Head Color
What functions might the red-tailed hawk’s variable head color serve? Light head color could camouflage a hawk from below against bright sky as it searches for prey. Darker crown feathers may help break up its silhouette against the ground when viewed from below. Contrasting facial markings may help hawks identify and communicate with each other in flight. Distinctive plumage patterns may also play a role in attraction of mates.
Researchers continue to study how different factors like genetics, nutrition, environment, and behavior come together to determine plumage. But whether light or dark, uniformly brown or distinctly streaked, the Red-tailed Hawk’s head coloration serves the vital functions of survival and reproduction.
Conclusion
The Red-tailed Hawk shows a high degree of individual and regional variability in the coloration of its head feathers. However, some consistent patterns emerge. Adults have primarily brown crowns and napes with whitish mottling on the neck and cheeks. The reddish-brown tail gives this species its name, not the typical head coloration. Both diet and genetics likely play a role in the shades of brown displayed. While variable, the Red-tailed Hawk’s head color serves the important purposes of camouflage, communication, and mate attraction. So next time you see a Red-tailed Hawk soaring overhead, take a closer look at its complex plumage for clues into its life history and origins.
| Age | Head Color |
|---|---|
| Hatchling | White and gray down |
| Juvenile | Brown with streaking |
| Immature | Brown with white mottling developing |
| Mature Adult | Solid brown crown, white mottled throat and neck |
Regional Variation in Red-tailed Hawk Head Color
| Region | Head Color |
|---|---|
| Western North America | Pale whitish-brown |
| Eastern North America | Darker brown |
| Southwestern U.S. | Rufous-tinged |
| Pacific Northwest | Dark with white mottling |
Factors Influencing Red-tailed Hawk Head Color
| Factor | Effect on Color |
|---|---|
| Age | Darker with maturity |
| Diet | Carotenoids deposit reddish and brown hues |
| Genetics | Controls melanin production |
| Region | Environmental and prey variability |
Functions of Red-tailed Hawk Head Color
| Function | Explanation |
|---|---|
| Camouflage | Blend in against ground and sky |
| Communication | Facial contrasts identify individuals |
| Mate Attraction | Brighter colors attract mates |
| Thermoregulation | Darker feathers absorb heat |
In summary, the head coloration of Red-tailed Hawks serves many important functions related to their survival and reproduction. The striking plumage patterns result from the interplay of developmental, genetic, environmental, and dietary factors across the species’ broad geographic range. With their variable but distinctive heads, Red-tailed Hawks remain one of the most recognizable raptors gracing the skies of North America. Careful observation can reveal the intriguing influences behind nature’s color palette.
