By Gael Bissell
It’s a quiet cold December day and as I drive into town… out of the corner of my eye I see a largish dark raptor perched on a power pole staring into the grassy-snowy ditch along the road. I slow down, but it’s not safe to stop or take a good look. I turn the car around and cruise gently past the bird. I am delighted to see the determined concentration of a beautiful adult Red-tailed Hawk keeping its balance in the wind, and maintaining focus on something moving on the ground below. Although Redtails are one of our most common hawks here in both winter and summer, you may wonder why I smile when I see “just another Red-tailed Hawk”? Well, got a minute?
Several decades ago, there were two zealous undergraduate zoology students (one of whom was Dr. Jack Kirkley, now a Biology professor at UM-Western in Dillon and active Audubon member) who were attending a small midwestern college. One day, these two students discovered the awe of “birds of prey” and decided to embark on a raptor research project. They decided to track down every pair of Red-tailed Hawks and Great-horned Owls within 15 miles of town, climb huge hardwood trees with ropes or use a mirror mounted atop a long, extendable pole to look into every nest, and set up a research blind high in an old oak tree overlooking a soon-to-be-occupied Redtail nest. It wasn’t long after they started this crazy project that these students shared their incredible and rare close-up hawk photos with me.
Before long, I was also out searching for nests, climbing up trees, and sitting in that blind for hours at a time. I felt like the luckiest person in the world as I watched two tiny fluffy white, clumsy chicks with oddly oversized feet hatch out. I can recall the various loud calls that the adults used to warn each other of intruders and then the more subtle calls that let each other know when they were returning to the nest with rodents or snakes. I watched in fascination as the adult female used those clawed feet to hold the carcass and then rip and tear the prey into innumerable bite-sized shreds but then ever so gently feed the tiny morsels to each chick. I watched wide-eyed as the chicks grew into awkward teenagers flapping wings and jumping wildly around the nest and then becoming gorgeous young birds shedding the last of their down before finally flying off.
To a 19-year old inexperienced zoology undergrad, these birds were something else… more like flying, feathered, velociraptors with sharp beaks and yellow clawed feet living out a strange and foreign life in a tree only about a mile from my dorm room. It’s been years since this formative experience but I am still enthusiastic and somewhat nostalgic about the Red-tailed Hawk.
The Red-tailed Hawk, Buteo jamaicensis, is one of the stockier North American buteos that hunt during the day in mostly open country. This bird-of-prey has the typical buteo shape with rounded wings that can stretch 4 feet across; they are about 19 inches long from head to tail. Like other hawks and eagles, female Redtails are larger than males and can weigh up to three lbs.
Redtails will hunt the most common prey available in open country (e.g., voles, mice, rabbits, ground squirrels, tree squirrels, grouse and snakes, etc.) and have adapted well to areas of human development, such as agricultural lands, parks, suburban areas, and transportation and energy corridors across North America.
The Red-tailed Hawk is a perfect generalist, an adaptive and versatile creature that many call the “jack of all trades.” It has an uncanny ability to not only hunt from open perches (its primary mode of hunting) but also to soar, kite, and swoop to catch prey.
Once called “chicken hawks” and killed because of their tendency to hang around small farms, Redtail numbers have increased steadily since the 1960’s. (In reality, Redtails rarely kill chickens, although they may take a chick or two; these birds are often highly beneficial to farmers because they prey on a variety of rodents.) Partners in Flight estimate that there are around 2.3 million Redtails in North America today.
As winter begins to recede, Redtails begin their spectacular aerial courtship displays. A pair may soar together in wide circles high up in the air.
Vocalizations (yes, the screeching calls you hear in nearly all Hollywood movies) are common, particularly in boundary disputes between territorial pairs. I heard this call only a few weeks ago as I watched a larger Redtail chase off a smaller intruder from her apparent “winter” territory.
Red-tailed Hawks are very acrobatic. To attract females, males may make steep dives and ascents and then may lock talons with the female and spiral toward the ground. Both male and female help build fairly large stick nests, usually near the trunks of the larger trees in woodlots or patches of trees where they can easily observe their surroundings. They may use the same nest year after year. Often Great Horned Owls, one of the dreaded predators of Redtail young, takes over and uses Redtail nests. Redtails are most sensitive to disturbances during the incubation period of the nesting season and may abandon their nests if disturbed at that time.
Red-tailed Hawks vary widely in coloration across their range, with transitional color patterns occurring where subspecies’ ranges converge. There are five distinct subspecies: Eastern, Southwestern, Western, Krider’s, and Harlan’s. All subspecies except for the Western’s dark morph and the dark Harlan’s have a light under-wing with a blackish mark on the lighter underside of the leading edge of the wing as well as a dark “comma” just beyond the “wrist” of the outer wing. Most adult Redtails have the striking rufous tail. In contrast, most juvenile Redtails are generally white or pale when viewed from below with brown-banded tails. Individuals of the Southwestern subspecies typically have darker backs and wings but are generally much paler underneath. The Western subspecies (typical of our area) tends to have darker streaking and a belly band (juvenile) with a rufous wash on the undersides (adult). But beware, about 20% of the Western subspecies includes a dark morph where the adult is entirely black on the back and belly and has a red tail while the dark morph juvenile has a pale tail.
To add to identity confusion, the rare Harlan’s subspecies that breeds in Alaska and northwest Canada migrates and winters through the Flathead and Mission Valleys. The adult Harlan’s is completely dark on back, head, and belly but it has variable white streaks on its chest and a white tail (not red). The juvenile Harlan’s is not readily distinguishable from the Western dark morph making positive identification of subspecies on the Christmas Bird Count an annual challenge.
With the advent of digital cameras, live streaming and “Nature” channels, anyone can watch and listen to these fascinating birds-of-prey during the nesting season. To experience hours of calm incubation punctuated by territorial defenses followed by the tearing and feeding frenzy that emits a “velociraptorial” feeling that I once had, visit the Cornell University campus webcam (URL) next spring (http://cams.allaboutbirds.org/channel/16/Red-tailed_Hawks).