- Red-bellied Woodpecker Guide - October 31, 2022
- Calliope Hummingbird Guide (Selasphorus calliope) - October 19, 2022
- Northern Flicker Guide (Colaptes auratus) - October 10, 2022
Introduction
Birds of prey raise mixed emotions among birdwatchers and nature lovers, and a sighting of a hawk can elicit strong reactions from different people.
To many, witnessing a predator utilizing its skills and adaptations on a hunt is one of the great thrills we can hope for from a day out with binoculars. Others see a hawk and fear that it might be hunting for the small songbirds. Nature has no interest in such sentiment, though; whatever our opinions are, hawks will be hawks.
Hawk Taxonomy
Hawks are birds of prey, also known as raptors, in the family group Accipitridae, which includes Hawks, Eagles, and Kites, covering 250 species of 70 different genera.
The term ‘hawk’ can be somewhat subjective, birders can use the name to cover a variety of species, but for this article, I’m going to focus on two particular groups of birds that are most familiar as hawks, the buteos and accipiters. Three of the 45 accipiters worldwide occur regularly in North America, as do 8 of the 27 buteos.
- Accipiters
- Sharp-shinned Hawk (Accipiter striatus)- North, Central, and South America
- Cooper’s Hawk (Accipiter cooperii)- South Canada and the United States of America
- Northern Goshawk (Accipiter gentilis)- North and western North America
- Buteos
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- Gray Hawk (Buteo plagiatus)- Extreme southwest United States of America and Central America
- Red-shouldered Hawk (Buteo lineatus)- Southeast Canada, east and far western United States of America
- Broad-winged Hawk (Buteo platypterus)- Breeds in the south and southeast Canada, eastern United States of America, winters in Central and South America
- Swainson’s Hawk (Buteo swainsoni)- Breeds in the west and central Canada and the United States of America, winters in southeast South America
- Red-tailed Hawk (Buteo jamaicensis)- All of North America except far north
- Ferruginous Hawk (Buteo regalis)- West and central North America
- Short-tailed Hawk (Buteo brachurus)- South Florida, Central, and South America
- Zone-tailed Hawk (Buteo albonatus)- Southwest United States of America, Central, and South America
- Rough-legged Hawk (Buteo lagopus)- Breeds in the Arctic, winters across North America
Hawk Characteristics
Hawks have many typical characteristics of birds of prey that allow them to be efficient hunters. With broad wings, they can catch thermals of rising warm air, keeping them airborne with minimal effort as they search either for the movement of prey or for a suitable perch in good habitat.
The wings are also often relatively short, which is necessary when flying rapidly through dense vegetation. Their tails are long and used as a rudder to increase their agility. Solid and long legs with large talons are essential for catching and penetrating prey and hooked beak tears apart a freshly caught meal.
However, all of these would be useless without the exceptional eyesight that hawks have. From their flight position or chosen perch, they can quickly spot the tiny movements of small prey and move in for the kill.
Accipiter Hawks – The Smallest Hawk: Sharp-shinned Hawk (Accipiter Striatus)
At just 25 to 35 cm, Sharp-shinned Hawks, also known as ‘Sharpies,’ are tiny for a bird of prey, unlike the images in our minds of giant mighty eagles and hawks. They are no less effective as predators, though. Sharpies are super efficient hunters and use their small size to their advantage.
Being small allows them to focus on small prey, which is very convenient as songbirds are often found in large numbers in all habitats, resulting in excellent prey availability.
Sharp-shinned Hawks are found almost all over North America, wherever there is woodland habitat. They are also present in South America, as far south as Argentina, but there is some debate about whether the birds south of Mexico are a different species.
Hunting
They use their small size in their woodland habitats to dart rapidly through vegetation and ambush unsuspecting small birds. Like many birds of prey, Sharpies have strong sexual dimorphism; the females are much larger than the males, sometimes 50% heavier.
Allowing the two sexes to target prey of different sizes reduces conflict and competition for food and gives a breeding pair access to a more extensive food resource. Males will primarily go for warblers and sparrows, and females have the strength to take larger birds like thrushes and woodpeckers.
They have relatively short wings and long tails, giving them the maneuverability to fly rapidly through wooded habitats and the agility to change direction quickly in pursuit of their prey.
Identification
Adults are blue-grey on the upper parts, with females slightly duller and browner than males. The underside is variably barred, rufous, and white, with females generally having sparser barring and being more white. The face is also variably white-rufous. The tail has broad dark bars, particularly noticeable on the underside of the tail in flight.
The underwings are barred, dark and white. Juveniles are brown above and have pale underparts with brown streaks on the chest. The flight action is distinctive, with rapid flicking wingbeats interspersed with short glides and occasional soaring.
Not a Sharp-shinned Hawk: Cooper’s Hawk (Accipiter Cooperii)
One of the most frequent bird identification conundrums facing North American birdwatchers is: was that a Sharp-shinned Hawk or a Cooper’s Hawk? Even experienced birders are sometimes left scratching their heads and writing ‘accipiter sp.’ in their notebooks after encountering one of these.
Cooper’s Hawks are a little larger than Sharpies, but sexual dimorphism can make this a tricky tool. A large female Sharp-shinned is similar in size to a male Cooper’s. The tail shape is a good pointer for identifying flying birds; Cooper’s has a rounded tail tip and is more square on Sharpies.
Hunting
As is typical for an accipiter hawk, Cooper’s Hawks hunt primarily by flying rapidly through woodland or along hedgerows, and forest edges, to surprise and ambush small birds.
Identification
Like Sharpies, adult Cooper’s Hawks are blue-grey on the back and upper wing, with rufous and white barred underparts. Juveniles are brown above, with brown streaks on a white belly. Cooper’s Hawks often have darker tones to the top of the head, giving them a capped appearance.
The most Powerful Hawk: Northern Goshawk (Accipiter Gentilis)
The quickest explanation of the Northern Goshawk’s size is that it is not unusual for them to hunt the previously mentioned species, the Sharp-shinned Hawk.
The Northern Goshawk is a hawk that eats other hawks! Even the name Goshawk is a derivation of ‘Goose Hawk’, referring to the fact that falconers keeping Goshawks would use them for hunting large waterfowl, although other smaller quarry species were more regular prey.
Goshawks have always been a famous falconry bird, considered effective at catching prey, if not as glamorous as flying a falcon.
Goshawks are an enigmatic bird found chiefly in boreal forests in Canada and Alaska and temperate forests in western North America, particularly in mountainous areas.
Like many birds of prey, Goshawks are considered a ‘partial migrant,’ with birds in the most northern and upland regions moving south or downhill as the weather deteriorates and prey availability reduces in the fall and winter.
They are also found throughout Europe and Asia, always in woodland habitats. Interestingly, they have recently established in urban areas in parts of Europe, nesting in small woodland fragments and hunting in parks and gardens.
Hunting
Being such a large bird, Goshawks are blessed with a wide range of prey options and have been recorded hunting a variety of species of mammals and birds.
They target medium-sized mammals like squirrels, rabbits, and birds, including corvids and pigeons, but are opportunistic and will attempt to take almost anything they come across.
They have even taken other raptors regularly, including those as big as Red-tailed Hawk! They usually sit still on a perch within the woodland, waiting to see movement from potential prey before launching a short ambush flight.
Identification
Goshawks are distinctive birds with dark blue-grey upper parts and barred under parts. The tail is long, with bold dark barring. The cap is dark grey, separated from a dark face patch by a bold white stripe over a beautiful dark red eye. They are one of the larger hawks, but this is complicated by sexual dimorphism.
While most goshawks weigh around 1 kilogram, a small male could be about 700 grams and a large female up to 1300 grams. The wingspan is approximately 1 meter. Juveniles are browner above, with dark brown streaks on the chest.
Buteo Hawks – The Southern Hawk: Gray Hawk (Buteo Plagiatus)
The Gray Hawk only just qualifies as a North American bird species, with less than 100 nesting pairs limited to the southern edges of Texas and Arizona, but their overall range stretches south to Costa Rica.
Hunting
This species is restricted to the edges of dry forests, where they hunt primarily for lizards and snakes, and they are forced to migrate south out of the United States in the fall as the abundance of this prey reduces.
Identification
The name is accurate, and they are very much a gray-colored bird, with uniform gray upper parts and a gray and white barred underside. In flight, it is possible to see the boldly black and white barred tail.
The Noisy Hawk: Red-shouldered Hawk (Buteo Lineatus)
This bird generally keeps a low profile but reveals its presence through loud vocalizations. Red-shouldered Hawks spend much of their time deep within their preferred woodland habitat, nesting, and hunting.
Hunting
They sit quietly on a low branch to spot their prey, rather than sparing in the open sky or sitting on an exposed perch like many other hawks.
This can make them difficult to see, but if a pair is nesting near you, you will probably first notice them during the courtship phase in the spring. At this time, they may engage in ‘sky-dancing’ where both birds soar high in the sky, and the male performs steep dives, often with both birds shrieking loudly. If the noise continues from within the woodland afterward, this is a good sign that the ritual was successful.
Identification
The overall plumage is variable but always with rufous tones, particularly on the head, back, and chest. The upper wing has a neat black-and-white pattern, and the tail is black with thin white bars. The red shoulders are discreet and often hidden by the closed wing of a perched bird.
The Flocking Hawk: Broad-winged Hawk (Buteo Platypterus)
Broad-winged Hawks are an abundant breeding species in eastern North America during the summer, but their habit of spending most of their time deep within the forest makes them a tricky species to see.
Migration
They become suddenly, and often spectacularly, apparent during migration, particularly in the fall. As individual Broad-winged Hawks move south, they follow the same routes of the best thermals and become concentrated in places, sometimes forming flocks of several thousand birds.
The best of these sites, like Hawk Mountain, Pennsylvania, and Hawk Ridge, Minnesota, often have fall events known as ‘hawk-watches’ and are fascinating sites to watch bird migration in action and learn from friendly expert birdwatchers.
Identification
Adult Broad-winged Hawks are distinctive in flight, with pale underwings, a neat black border to the trailing edge, and a boldly barred black and white tail.
The Migratory Hawk: Swainson’s Hawk (Buteo Swainsoni)
While many of the hawks we might see in North America are with us throughout the year, spending their whole lives within a particular territory, some are migratory. The northernmost populations of Cooper’s and Sharp-shinned Hawks may move a thousand kilometers south in the fall to escape the worst weather.
Broad-winged Hawks travel through Mexico to reach Central America. Still, the Swainson’s Hawk undertakes a remarkable journey that blows the others away.
Migration
From their summer breeding grounds throughout western North America, including as far north as Alaska, the entire population of Swainson’s Hawks migrates not just to Central America, or even to the north of South America, but down to Argentina, nearly to the farthest part of South America, an incredible journey of more than 10,000 kilometers each way.
This is the second longest migration of any raptor, beaten only by the Peregrine Falcon.
Hunting
Their alternative name of ‘Locust Hawk’ explains the need for this migration. Swainson’s hawks usually breed in open country, dominated by grasslands, but with some trees or woodland for nesting. They hunt for rodents and ground squirrels in the grasses.
This prey declines in abundance in the winter, so the Swainson’s Hawks decided to take advantage of the bounteous number of invertebrates on offer in South America and migrate to the plains and pampas of Argentina to hunt locusts and grasshoppers in massive amounts.
They will hunt them either by running around on the ground, snatching them up, or catching them in flight.
The Familiar Hawk: Red-tailed Hawk (Buteo Jamaicensis)
The Red-tailed Hawk is a species that anyone in North America with more than a passing interest in birds will be familiar with. They are found across North America, breeding from Alaska south to Mexico and The Caribbean.
They occupy various habitats throughout their range, typically found in open woodland, nesting in trees, and hunting in more open areas.
They are even found in semi-desert areas, nesting in giant cacti. Recently, Red-tailed Hawks have adapted to urban life, nesting on ledges on buildings in the largest cities and hunting in nearby parkland.
Hunting
Red-tailed Hawks mostly take mammal prey, particularly rodents like voles, mice, and rats. In open agricultural areas, rabbits and hares are an essential food resource.
They are opportunistic hunters and usually sit patiently perched, watching and waiting for signs of movement from a potential prey item close by, before dropping to the ground to catch it or sometimes flying a short distance either in pursuit or trying to take it by surprise.
This tactic can result in a large variety of prey being taken. Anything that mistakenly wanders into range, including small birds, snakes, and even large insects, is targeted.
As well as this ‘still hunting,’ in some locations, they have been seen waiting outside a bat roost site and hunting the bats in flight as they depart in the evening or returning in the early morning’s half-darkness.
Identification
As the name suggests, the tail color is the best identification for this species. No other bird of prey in North America has that distinctive orange-red tail. But beware, juvenile Red-tailed Hawks have a grey-white tail and don’t develop the colors until around three years old.
This is also an extremely variable bird, with 14 subspecies and light, intermediate and dark morphs. The appearance of the Red-tailed Hawks you see will vary drastically depending on where you live. Some can be almost completely clean white on the undersides, while some are dark brown, almost black all over.
The Largest Hawk: Ferruginous Hawk (Buteo Regalis)
If you’re driving across the western United States of America and see a bird perched next to the road that you can’t decide is an eagle or a hawk, it is probably a Ferruginous Hawk.
Hunting
Ferruginous Hawks are birds of open country, grasslands, and deserts, hunting for rabbits, ground squirrels, and prairie dogs. The lack of trees in these habitats concentrates them on available perches, helping birdwatchers to spot them.
Human-made perches like fence-posts, telecommunications towers, and electricity pylons provide ideal sites for these birds for both nesting sites and hunting lookouts. These structures are often located close to roads, and playing ‘spot the Ferruginous Hawk’ is a way of passing the time on a long cross-country drive.
Identification
This is the largest Hawk in North America, with a wingspan of 1.5 meters and a fierce look to go with it. The plumage is variable, but as the name suggests, there is often an element of rufous coloration, usually on the back and wings. The chest and belly vary from white to dark brown.
The Florida Hawk: Short-tailed Hawk (Buteo Brachurus)
If you want to see a Short-tailed Hawk in the United States of America, you have to go to Florida, and even then, it will be difficult. Only around 200 pairs are found there, nesting primarily in the dense forest of The Everglades.
Hunting
Their hunting technique doesn’t help to spot them, as they soar at altitudes of up to 250 meters, using their phenomenal eyesight to spot small birds perched in treetops before diving down at great speed to snatch their prey before eating it within the cover of the forest.
Identification
If you are lucky enough to see one, don’t be fooled by the species’ name when making your identification. Short-tailed Hawks do not have short tails at all! The plumage can also be confusing, with dark and light morphs that appear pretty unlike each other.
The Mystery Hawk: Zone-tailed Hawk (Buteo Albonatus)
The Zone-tailed Hawk is one of the least studied North American bird species, and it’s not hard to understand why.
Although they have an extensive range across South and Central America, they only sneak into the southwestern United States, where around only 100 pairs nest in isolated canyon country, in trees on steep and difficult-to-access slopes, usually next to a river.
In the winter, they depart south to Mexico.
Hunting
They usually hunt over rocky, open country, searching for reptiles and mammals. In this hot environment, there is much rising warm air to help large, soaring birds stay aloft with minimal effort, and Zone-tailed Hawks use this assistance to significant effect.
Zone-tailed Hawks have a flight action similar to Turkey Vultures, soaring with their wings held slightly raised in a shallow ‘v’ shape and rocking from side to side as they fly. Being oversized and mostly black-plumaged, they mimic soaring Turkey Vultures not to alarm potential prey.
Vultures do not catch live creatures and can be numerous, so smaller animals learn not to run away and hide from them, as this would be an unnecessary waste of precious energy. A basking lizard could easily mistake them for a passing vulture and not notice the threat, making a successful hunt more likely for the Hawk.
This is a fascinating example of nature’s intricacies, especially the neat adaptations needed to survive in hostile environments like arid canyon country.
The Arctic Hawk: Rough-legged Hawk (Buteo Lagopus)
This is a hawk that requires a bit of effort to see and won’t be visiting your backyard unless you live in the Arctic or on a farm.
Hunting
Rough-legged Hawks nest only in the Arctic tundra, where they hunt small mammals like Lemmings. The Arctic becomes a very hostile place in the winter, and thick snow cover makes it hard for them to find their prey.
Because this environment has few trees to perch, Rough-legged Hawks have a distinctive hunting technique where they spend much time hovering over the open ground looking for their prey, unlike most other hawks.
Rough-legged Hawks migrate south to open agricultural areas, and plains south Canada and north and west United States of America, and this is where most birders get to see them.
Identification
Rough-legged Hawks have a quite pale overall impression, almost frosty like their summer home. The head and underside are white or buff-white, with variable brown streaking, often forming a dark patch on the belly. The tail pattern is very distinctive in flight, particularly when hovering. Most of the tail is white, with a dark band at the tip.
The Fish Hawk: Osprey (Pandion Haliaetus)
The Osprey could be considered a contentious inclusion in this article about hawks, many birdwatchers and taxonomic authorities classify it as the single representative of its own family, Pandionidae, rather than a member of Accipitridae.
But this is a widespread and familiar bird of prey found worldwide, known to many people as the Fish Hawk or River Hawk.
The Osprey is an excellent example of the variety amongst birds and how a bird that initially looks similar to other hawks can make its living in such a drastically different manner. The name ‘Fish Hawk’ gives it away.
The Osprey feeds solely on fish, unlike the other hawks we’ve been learning about. Ospreys are found in many different habitats in marine and freshwater environments; saltmarshes, coastal cliffs, canals, and forest pools; they’re happy anywhere with plentiful fish.
Ospreys are only summer visitors to most of the Northern Hemisphere. In North America, they breed across Canada and Alaska, along both Pacific and Atlantic coasts, and many freshwater habitats in the interior United States of America, with these populations migrating to Central and South America for the winter.
There is a resident population in Florida and the Gulf of Mexico. In Europe, they only arrive for the summer, and those birds spend their winters in Africa. They are also residents south of the equator in Australia and Southeast Asia.
Hunting
Ospreys fly, often hovering over the water, visually searching for fish swimming very close to the surface. Upon seeing a target, they bring their wings in and plunge into the water, with outstretched feet reaching into the water first. The feet have a few neat adaptations and differences from other hawks to catch fish successfully.
The underside of the foot is covered in little spikes, which gives them an excellent grip to hold on to a slippery catch. They can also change the position of their toes to get a better grip on the fish as they fly from the hunting site to a perch where they can eat it.
Ospreys can’t sit on the water to eat their catch as seabirds do, so they must take it to a tree, a post, or a rock, or maybe sit on a beach to eat it.
Identification
Ospreys are distinctive birds, larger than most hawks, with relatively long wings. They are strongly bi-colored, brown-black on the upper parts, and mostly white underneath, with dark markings on the underwing. The head is white, with a broad dark band through the eye. When seen up close, the iris is a bright golden yellow.
FAQs
Answer: If you feed the small birds in your yard, there is a very good chance that you receive regular visits from a hawk, even if you haven’t noticed it. Anywhere that a large number of small birds gathers is likely to gain attention from predators.
Hawks will, of course, hunt the small birds in your garden, and this might well be something that you consider to be a thrilling demonstration of the mercilessness of nature.
There is not much you can do if you don’t like to see predation in action, but placing feeders close to thick bushes that small birds can escape into and hide gives them more of a chance. If you have a larger yard or garden, consider moving feeders, as this could disrupt a hawks hunting ‘routine.
While it will be disastrous for any individual songbird taken for a hawk, there is no evidence to show that hawk predation has any significant impact on prey populations, a far greater risk comes from the spread of avian diseases, so make sure you clean your feeders regularly to keep your local ecosystem healthy.
Answer: The rarest species of hawk in the world is the Ridgway’s Hawk (Buteo ridgwayi), which is found on Hispaniola in The Caribbean. Only 300-400 of these birds survive in the wild, most in Los Haitises National Park, Dominican Republic.
Answer: Hawks can pose quite an identification challenge to inexperienced birdwatchers. It takes time to get familiar with their different shapes and plumages. With practice, it is possible to identify even the distant silhouette of a high-flying overhead hawk.
Key things to look out for include the length of the tail, is it square or round-ended, are the wings evenly broad, bulging on the trailing edge, is the tail barred? Features like this are often surprisingly visible even at long range. Check out our individual species pages for detailed identification information.
Answer: The smallest hawk in the world is the aptly named Tiny Hawk, which is found in tropical lowland forests in Central and South America. This diminutive hawk weighs between 75 and 100 grams and is just 25 centimeters long. They hunt small birds, including hummingbirds in the forest.
Answer: Yes, some hawks do migrate, usually depending on how far north they nest. Often a species has a broad range, and many can stay resident all year round, but for northern populations whose prey availability reduces in winter, it is necessary to move south.
Some travel just a few hundred kilometers, but others, like the Swainson’s Hawk, can travel from Alaska to South America!
Conclusion
While we might all be familiar with the existence of hawks, many people are surprised to discover just how variable they are as a species group. From the fish-eating Osprey to the Arctic-nesting Rough-legged Hawk, there is a lot of diversity from the woodland-hunting and garden-raiding hawks that most of us are used to seeing.
Hawks are found in so many different habitats and environments that we all have opportunities to see them, and getting to know their different plumages and hunting techniques is one of the great joys of birdwatching.
Research Citations:
- Winkler, D. W., S. M. Billerman, and I. J. Lovette (2020). Hawks, Eagles, and Kites (Accipitridae), version 1.0. In Birds of the World (S. M. Billerman, B. K. Keeney, P. G. Rodewald, and T. S. Schulenberg, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA
- Squires, J. R., R. T. Reynolds, J. Orta, and J. S. Marks (2020). Northern Goshawk (Accipiter gentilis), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA
- Bechard, M. J., C. S. Houston, J. H. Sarasola, and A. S. England (2020). Swainson’s Hawk (Buteo swainsoni), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA.
- Bierregaard, R. O., A. F. Poole, M. S. Martell, P. Pyle, and M. A. Patten (2020). Osprey (Pandion haliaetus), version 1.0. In Birds of the World (P. G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA
- Anderson, D. L., R. Thorstrom, C. D. Hayes, T. Hayes, M. Curti, and P. F. D. Boesman (2021). Ridgway’s Hawk (Buteo ridgwayi), version 2.0. In Birds of the World (T. S. Schulenberg and B. K. Keeney, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA.
- Lockwood, W.B. (1993). The Oxford Dictionary of British Bird Names. OUP. ISBN 978-0-19-866196-2.
- Sarasola, J. H. and J. J. Negro. (2005). Hunting success of wintering Swainson’s Hawks: environmental effects on timing and choice of foraging method. Canadian Journal of Zoology 83 (10):1353-1359.
- Reynolds, R.T., Joy, S.M. and Leslie, D.G. (1994). Nest productivity, fidelity, and spacing of Northern Goshawks in Arizona. Studies in Avian Biology. 16: 106-113.
- Kerlinger, Paul (1989). Flight Strategies of Migrating Hawks. Chicago: The University of Chicago Press. pp. 57–58, 153.
- Ferguson-Lees, J.; Christie, D. (2001). Raptors of the World. London: Christopher Helm. ISBN 978-0-7136-8026-3.
- Clark, William S. (2004). “Is the zone-tailed hawk a mimic?”. Birding. 36 (5): 495–498.
- Ogden, J. C. (1988). “Short-tailed Hawk.” In Handbook of North American birds. Vol. 5. Diurnal raptors. Pt. 2., edited by R. S. Palmer, 34-47. New Haven, CT: Yale Univ. Press.
You can read more about these hawks on their species pages: