swainson’s hawk
1. Bird Name
English name: Swainson’s Hawk
Scientific name: Buteo swainsoni
2. Appearance
The Swainson’s Hawk is a strikingly elegant bird with several distinct color morphs. Its colour ranges from light to dark variations but primarily, these hawks have light-coloured underbellies with darker-toned backs. The back can range in color from a chocolate brown to a near-black, often exhibiting some feathered flecking. This bird’s face has a distinctive dark “bib” punctuated by a broad, white forehead, giving it a hooded appearance. A typical specimen would have a long, slender pointed beak, and a medium-sized tail that is white with a band of black at the end. Eye color varies from light brown to dark brown and there is no apparent difference in the physical appearance of males and females.
3. Size
Swainson’s Hawks are relatively large birds, measuring between 43 to 56 centimeters (17 – 22 inches) in length. The birds boast a wingspan of an impressive 117 to 137 centimeters (46 – 54 inches), with weights ranging between 800 grams to 1,300 grams.
4. Habitat & Distribution
Swainson’s Hawks inhabit a wide range across the western portion of North America, from Alaska to Northern Mexico. They prefer open grasslands, agricultural fields, deserts and prairies. Remarkably, they make a long-distance migration every winter, journeying into South America to regions like Argentina and Uruguay.
5. Interesting Facts
Swainson’s Hawks are often referred to as ‘grasshopper hawks’ or ‘locust hawks’ due to their preference for these insects. They are one of the longest migrating hawk species, covering a staggering 8,000 kilometers in their journey from North to South America. They are also unique in that they frequently form communal roosts during migration, with numbers reaching into the thousands.
6. Diet
As its nickname suggests, the Swainson’s Hawk has a strong dietary preference for insects particularly grasshoppers and locusts. Its diet also includes small mammals like mice and ground squirrels, snakes, birds, and in lean times, carrion.
7. Behavior & Sounds
Swainson’s Hawks are powerful flyers, known for soaring on thermals during migration. In terms of sounds, they often give a plaintive, high-pitched whistling cry while soaring. During breeding and nesting seasons, they exhibit various aerial displays, which include soaring in wide circles and making steep dives.
8. Conservation Status
According to the IUCN Red List, the Swainson’s Hawk is currently categorized as least concern. However, due to habitat loss and exposure to pesticides, their populations have shown a moderate decrease.
9. Lifespan
Swainson’s Hawks typically live up to 16 to 20 years in the wild. There are fewer data for their lifespan in captivity, but in general, hawks tend to live longer in captive environments due to controlled diets and absence of predators.
10. Additional Notes
In Spanish-speaking regions, they are often referred to as Aguilucho langostero while in French they are called Buse de Swainson. They play a vital role in controlling the population of certain pests, particularly grasshoppers and other insects, thus benefiting crop growers and maintaining a balanced ecosystem.
