The Rough-legged Hawk (Buteo lagopus) is a large bird of prey found in Arctic and subarctic regions. It has several common names that reflect its appearance and habitat. The most widely used common name for this species is “Rough-legged Hawk.” Other common names include “Rough-legged Buzzard,” “Rough-legged Falcon,” and “Roughleg.” The name “Rough-legged Hawk” refers to the feathered legs of this species, which help insulate it in cold environments. In this article, we will explore the origins and usage of the common name “Rough-legged Hawk” for this species.
Physical Description
The Rough-legged Hawk is a relatively large, broad-winged buteo, or soaring hawk, measuring 18-26 inches in length with a wingspan of 50-60 inches. Adults have dark brown upperparts with dark streaks and a pale underside with dark spots. The legs and feet are fully feathered, giving them a “rough-legged” appearance compared to most other hawks. The feathers extend all the way down to the talons. The plumage varies between light and dark morphs. The light morph has a white head, neck, and underparts with a dark belly band. The dark morph is overall chocolate brown. Both morphs have black wrists and wing linings. The long, fanned tail has alternating bands of dark brown and white.
Range and Habitat
The Rough-legged Hawk breeds in the Arctic regions of North America and Eurasia. In North America, breeding grounds extend from Alaska across northern Canada. The species winters in southern Canada and the contiguous United States. It prefers open habitats like tundra, grasslands, and coastal areas. During winter, it can also be found in agricultural areas, fields, and wetlands throughout its migration range.
Origins of “Rough-legged Hawk” Common Name
The common name “Rough-legged Hawk” refers to the feathered legs that are a signature feature of this species. The earliest known use of the name “Rough-legged Falcon” dates back to the late 1700s. The species was originally classified in the genus Falco along with other falcons due to the similarities in appearance and hunting behavior. The first published use of the name “Rough-legged Falcon” appeared in English naturalist George Edwards’ 1770 book Gleanings of Natural History.
Over time, the species was reclassified into the genus Buteo with other soaring hawks. But the descriptive “Rough-legged” portion of the common name stuck. Ornithologists and naturalists continued to use the name Rough-legged Hawk or Rough-legged Buzzard to describe this distinctive feather-footed buteo. By the early 1800s, Rough-legged Hawk became the standard common name used in scientific references and birding field guides.
Other Common Names
While Rough-legged Hawk is the most widely used common name today, other common names have been used regionally or historically for this species, including:
– Rough-legged Buzzard: This name was once an alternate common name used in parts of Europe, reflecting the early classification as a falcon or buzzard rather than buteo hawk.
– Rough-legged Falcon: An early common name reflecting the original taxonomy as a falcon rather than buteo. Still occasionally used.
– Roughleg: An abbreviated version of Rough-legged Hawk. Often used by birders and in field guides.
– Rough-footed Buzzard: An alternate name used in parts of Europe, referring to the feathered legs and feet.
Usage of “Rough-legged Hawk”
Today, the common name Rough-legged Hawk is universally used in scientific literature and research to refer to this species. It appears in scientific publications, birding field guides, and databases documenting the species distribution and population.
Major ornithology references and databases using this common name include:
– The Cornell Lab of Ornithology’s Birds of North America online database
– The American Ornithological Society’s Checklist of North and Middle American Birds
– Peterson Field Guides
– The Audubon Guide to North American Birds
– eBird database of bird sightings
– The IUCN Red List of Threatened Species
Rough-legged Hawk has become the standard common name used by professional ornithologists and amateur birdwatchers alike when referring to this distinct raptor species. The name accurately describes the feathered legs that are unique to this buteo and also provides continuity by linking it to historical common names used for the species.
Reasoning Behind the Name
There are a few key reasons why Rough-legged Hawk became the standard common name for the species:
– Accuracy: The name directly describes the distinctive feathered legs, a feature unique among North American buteo hawks.
– Established use: After early common names like Rough-legged Falcon, the name Rough-legged Hawk was widely adopted in the 19th century and became entrenched in the scientific literature.
– Consistency: Using Rough-legged Hawk avoids confusion with regional variations or historical name changes between falcon, buzzard, etc.
– Intuitive meaning: The name immediately conjures an image of a large, rough-legged raptor for those familiar with the species.
– Connection to history: The Rough-legged portion links back to some of the earliest common names used for the species.
Overall, the common name Rough-legged Hawk provides an accurate, established, consistent, intuitive, and historically-linked name for this unique raptor species.
Conclusion
In summary, the common name Rough-legged Hawk refers to the feathered legs that are characteristic of this Arctic buteo species. The name has its origins in early descriptions like Rough-legged Falcon in the 18th century. It became established as the standard common name by the 19th century and is now firmly fixed in ornithological references and birding guides. While other regional names have been used historically, Rough-legged Hawk is now the universally accepted common name for this species among scientists, birders, and wildlife enthusiasts. The name captures the distinctive appearance of this raptor and continues the historical link back to some of the earliest known descriptions of the species by naturalists. So whether you call it Rough-legged Hawk, Rough-legged Buzzard, or Roughleg, you are referring to the same majestic feather-footed raptor that patrols the Arctic skies with its unique adaptations to cold northern environments.
Rough-legged Hawk Statistics
| Scientific Name | Range | Length | Wingspan | Weight |
|---|---|---|---|---|
| Buteo lagopus | Arctic and subarctic regions | 18-26 inches | 50-60 inches | 1.5-4.9 pounds |
Key Identification Features
| Feathered Legs | Broad Wings | Long Tail | Variable Plumage | Hover Hunting |
|---|---|---|---|---|
| Legs and feet fully feathered down to talons | Broad, rounded wings for soaring | Long, wide, fanned tail | Light and dark color morphs | Hovers frequently when hunting |
Plumage Variation
| Light Morph | Dark Morph |
|---|---|
| White head, neck, and underparts | Entirely chocolate brown |
| Dark belly band | Some retain white at base of tail |
| Black wrists and wing linings | Black wrists and wing linings |
Rough-legged Hawk Hunting and Feeding
The Rough-legged Hawk is an opportunistic feeder and employs a range of hunting strategies to catch prey. These include:
– Still-hunting – Perching and scanning the landscape for prey from an elevated perch. Once spotted, the hawk will swoop down to grab prey.
– Hovering – Fluttering or suspending itself in mid-air while hunting rodents or small birds. Allows for closer inspection of potential prey.
– Soaring – Flying slowly while scanning the ground for prey. Often seen soaring with wings in a dihedral “V” shape.
– Ground hunting – Walking along the ground to flush or pounce on prey like a hawk or falcon.
Preferred prey includes small rodents like voles, lemmings, and ground squirrels. It also takes other small mammals, birds, reptiles, and insects. It may scavenge carrion and roadkill when other food is scarce. Hunting success increases during population spikes of prey animals like lemmings or voles.
Migration and Wintering Habitat
The Rough-legged Hawk migrates between its Arctic breeding grounds and wintering habitat in Canada and the lower 48 states. Spring migration to the Arctic starts in March and April. Southward migration begins in September and October, peaking in November.
Wintering grounds include:
– Open grasslands
– Coastal marshes, mudflats, and beaches
– Agricultural fields
– Meadows and wetlands
The species is widespread throughout mid-latitude regions of central and western North America during winter months. Highest winter concentrations occur on the Great Plains and intermountain west.
Breeding and Nesting
The Rough-legged Hawk returns to the Arctic and subarctic each spring to nest and breed. Nesting occurs from May through July.
Nest sites are located on rocky outcrops, cliffs, or slopes with unobstructed views of the surrounding tundra. Both members of a breeding pair build the nest out of sticks, grass, and other vegetation.
The female typically lays 3-5 eggs that are incubated for 28-32 days. Both parents feed and care for the young after hatching. The young fledge the nest at 6 weeks old and remain dependent on the parents for another 6 weeks.
The Rough-legged Hawk has one brood per breeding season. It often migrates south again by September after successfully breeding and nesting during the brief Arctic summer.
Population and Conservation Status
The Rough-legged Hawk has an extremely large range and population. Partners in Flight estimates a global breeding population of 300,000 to 1 million individual birds. Population trends are generally stable, though some regional declines have occurred.
Due to the large population size, the species is classified as Least Concern on the IUCN Red List of Threatened Species. Partners in Flight also considers it a species of low conservation concern throughout its range in North America.
Potential threats include:
– Habitat loss and degradation
– Disturbance of nest sites
– Collisions with vehicles and infrastructure
– Exposure to pesticides and heavy metals
More research is needed to fully understand population threats for this species across its Arctic and subarctic distribution. Ongoing monitoring will be important to detect any emerging declines in this widespread buteo.
Where to See Rough-legged Hawks
The best opportunities to see Rough-legged Hawks occur during the fall migration and winter months. Prime viewing sites include:
– Open country along the Great Plains such as Pawnee National Grassland in Colorado or communities in eastern Wyoming.
– Agricultural regions of northern states like Minnesota, North Dakota, Washington, and Idaho where wintering raptors concentrate.
– Coastal marshes, mudflats, and beaches in California and the Pacific Northwest, where the hawks forage on rodents.
– Prairie pothole wetlands of the Upper Midwest, a core wintering area for the species.
– Alaska Highway and northern roads like the Dalton Highway where migrating Rough-legs can be seen in September and May.
With a keen eye and some patience, observers can spot the Rough-legged Hawk’s distinctive hovering and soaring flight styles as it hunts over open habitat. Look for the patterned black-and-white tail and wings. The feathered legs are visible in good viewing conditions and can confirm the ID.
Fun Facts About Rough-legged Hawks
Unique Feathers
The Rough-legged Hawk’s feathers extend all the way down their legs to the base of the talons. This “rough-legged” trait is unique among North American raptors.
Arctic Breeders
Rough-legged Hawks breed farther north than any other raptor species. Nesting grounds reach above the Arctic Circle.
Migration Marvels
Some Rough-legged Hawks undertake an extraordinary 10,000 mile round trip migration every year between the Arctic and southern wintering grounds.
Plumage Polymorphism
Rough-legs exhibit a dramatic light and dark plumage morph. The dark morph makes up about 10% of the overall population.
Ghostly Silhouettes
Pale winter adults can appear ghostly white when backlit against the sky, leading to spooky nicknames like “white ghost hawk.”
Louse Loaders
A study found Rough-legged Hawks carry up to 14 species of wing lice! The lice ride along to the Arctic and back each year.
Lemming Lovers
Rough-legged Hawk numbers fluctuate with the 3-4 year boom and bust cycle of lemmings, their primary prey in the Arctic.
Conclusion
The Rough-legged Hawk is an iconic and unique Arctic raptor. The common name accurately captures its identifying feathered legs while linking back to historical descriptions of the species. Rough-legged Hawk has become the accepted common name used in science and birding today for this widespread buteo species. With distinctive plumage and aerial hunting skills, the Rough-legged Hawk stands out as it migrates between its northern breeding grounds and southern wintering range. Birders flock to wintering areas for a chance to spot this majestic raptor in action over open skies.
