The designation “hawk” can be applied in a number of ways. It is sometimes used (inaccurately) to refer to practically any type of bird of prey excluding those of the Strigiformes order or the owls. In North America, the term is generally assigned either to falcons or to the smaller or medium-sized birds of the Accipitridae family, to which also belongs the eagle. However, it is the members of the genus Accipiter, from the Acciptridae’s Acciptrinae subfamily, which are considered as the “true hawks”.
Typically located in bushy or woodland regions, accipiters are physically distinguishable from the rest of their family by their absence of a procoracoid foramen. Other physical characteristics include their slender bodies; short, broad, rounded wings; and their long tails, which serve to help them maneuver while flying. They also possess long legs; long, sharp talons that they use in killing their prey; and a pointed hook-shaped bill. The females of this genus are usually larger in size than the males.
There are about 50 species in the genus Accipiter. One of them is Accipiter gentiles, or the Northern Goshawk, a prevalent species which resides in the northern hemisphere’s temperate areas. The largest bird of its genus, male Northern Goshawks measure 19-22 inches (49-57 centimeters) in length, have a wingspan of 37-41 in (93-105 cm) and weigh as little as 22 ounces (630 grams). Females are naturally larger at a length of 23-25 in (58-64 cm), a wingspan of 43-50 in (108-127 cm) and a weight of no less than 4.4 pounds (2 kilograms).
Accipiter nisus, the Eurasian Sparrowhawk, is a small-sized species situated throughout the subtropical and temperate regions of the Old World. Males mature to a length of 11-13 in (29-34 cm), a wingspan of 23-25 in (59-64 cm), and a weight of 3.9-6.9 oz (110-196 g). Again, female Eurasian Sparrowhawks are bigger, measuring 14-16 in (35-41 cm) in length, 26-31 in (67-80 cm) in wingspan, and 6.5-12.1 oz (185-342 g) in mass.
Accipiter trivirgatus, the Crested Goshawk, hails from tropical Asia and is a relative of other diurnal (daytime-active) birds of prey such as the buzzard, the eagle and the harrier. It generally comes at a length of 30-40 cm, with females, true to form, being much larger. Accipiter soloensis, the Chinese Sparrowhawk, have around the same size at a length of 30-36 cm. This Southeast Asian species is known to breed in Southeast China, Taiwan, Korea and Siberia, and passes the winter season in Indonesia and the Philippines.
Accipiter toussenelii, the Red-chested Goshawk, is indigenous to West Africa and belongs to the same species as the African Goshawk. Male Red-chested Goshawks have a wingspan of 7.2-8.0 in (18.4-20.3 cm) and a mass of 150-235 g, while the much-larger females have a wingspan of 8.0-9.6 in (20.4-24.3 cm) and weigh 170-265 g. Their lengths measure roughly 3/5 of their wingspan.
Accipiter francesiae pussillus, the Anjouan Island Sparrowhawk, is a rare species once widespread in Anjouan, an island belonging to the Union of Comoros. Also known as the Joanna Island Goshawk or the Ndzuwanni Goshawk, it has not been sighted since the 1950’s and could possibly be extinct. The males of this species have a 5.3-5.9 in (135-149 mm) wingspan and a 3.9-7.4 in (99-188 mm) long tail, while the females have a wingspan of 6.1-6.4 in (155-163 mm) and a tail measuring 4.4-4.9 in (113-125 mm) in length.