Broad-winged hawk

The broad-winged hawk (Buteo platypterus) is a small hawk of the genus Buteo. During the summer, some subspecies are distributed over eastern North America, as far west as British Columbia and Texas; they then migrate south to winter in the neotropics from Mexico south to southern Brazil. Other subspecies are all-year residents on Caribbean islands. As in most raptors, females are slightly larger than males. Broad-winged hawks' wings are relatively short and broad with a tapered, somewhat pointed appearance. The two types of colouration are a dark morph with fewer white areas and a light morph that is more pale overall. Although the broad-winged hawk's numbers are relatively stable, populations are declining in some parts of its breeding range because of forest fragmentation. The broad-winged hawk is a relatively small Buteo, with a body size from 32 to 44 cm (13 to 17 in) in length and weighing 265 to 560 g (9.3 to 19.8 oz). The tail is relatively short, measuring 14.5–19.0 cm (5.7–7.5 in) in length. The tarsus measures from 5.6 to 6.6 cm (2.2 to 2.6 in). As in most raptors, females are slightly larger than males. Broad-winged hawks have relatively short and broad wings, pointed at the end, which have a tapered appearance unique to the species. The wingspan can range from 74 to 100 cm (29 to 39 in), with the extended wing bone (standard measurement) measuring 22.7–30 cm (8.9–11.8 in). An adult's body is a dark brown with a white belly and chest containing horizontal barring. Its tail can be a dark grey-black with white lines along the middle, base, and tip. The young hawks have a slightly different colouring with more white and longitudinal barring instead of horizontal barring. The two types of colouration are a dark morph with fewer white areas and a light morph that is more pale overall. The light morph of this bird is most likely to be confused with the red-shouldered hawk, but it has a longer, more heavily barred tail and wings with a solid rufous colour in the adult, which are usually distinctive. Rare dark morphs are a darker brown on both upperparts and underparts. Dark-morph short-tailed hawks are similar, but are whitish under the tail with a single subterminal band. This species, Buteo platypterus, is in the family Accipitridae, which is placed in the order Falconiformes (or Accipitriformes). Currently, the species is split into six subspecies; each is named for its distribution, Broad-winged hawks have a wide range in North America and South America, from southern Canada to southern Brazil. Their breeding range is in the northern and eastern parts of North America, and some migrate in the winter to Florida, southern Mexico, and northern South America. Five subspecies are endemic to the Caribbean and do not migrate. Those subspecies that do migrate fly in flocks of more than 40 up to several thousand at heights from 550 to 1,300 m (1,800 to 4,270 ft). They soar using thermals to carry them through their journey of 3,000–6,000 km (1,900–3,700 mi). Fall migration lasts for 70 days as birds migrate about 100 km (62 mi) per day from North America, through Central America to South America without crossing salt water. The enormous flocks of soaring broad-winged hawks are termed kettles and are characteristic of many hawk migration spectacles in North America, such as at Hawk Cliff in Ontario, Hawk Ridge in Minnesota, Hawk Mountain in Pennsylvania, and the River of Raptors in Veracruz. Broad-winged hawks stay in areas up to an elevation around 2,000 m (6,600 ft). They breed in deciduous forests good for nesting and forage primarily in wetlands and meadows. While some birds have acclimatized themselves to living near humans, even those birds avoid human settlements and interactions. In the winter, the migrating subspecies of the hawks seek out similar conditions to their overwintering home, so they settle in deciduous and mixed forests. Although it is declining in some areas because of forest fragmentation, its numbers are relatively stable and is assessed as least concern on the IUCN Red List. These hawks use vocalizations for communication with their mates and offspring, and in territorial displays towards intruders such as red-tailed hawks or other threatening animals. Their call sounds like a very high-pitched kee-ee, almost like a whistle. When confronted with a threat, broad-winged hawks emit an alarm call consisting of stuttered and squealing whistles.