[order] ACCIPITRIFORMES | [family] Accipitridae | [latin] Accipiter soloensis | [authority] Horsfield, 1821 | [UK] Chinese Sparrowhawk | [FR] Epervier de Horsfield | [DE] Froschsperber | [ES] Gavilan ranero | [NL] Chinese Sperwer
Members of the genus Accipiter are small and medium-sized hawks, often called Sparrow-hawks or Goshawks. The females are almost invariably much larger than the males – in some cases weighing twice as much – a level of size dimorphism only exceptionally reached in any other genus Falconiformes. Their wings are short and rounded; the tail usually quite long. They are well adapted for flying through dense bush. Bird-catching Sparrow-hawks generally have long and slender legs, with slender digits, the middle one being especially long. Goshawks are usually larger, with shorter, thicker tarsi and digits and a shorter middle digit. Some smaller species have goshawk-like feet and vice versa, making it difficult on a world-wide basis to subdivide the genus on this or any other broad basis. Although many accipiters feed upon birds moreso than do other hawks, some species take many mammals, especially squirrels; others take lizards, frogs, snakes, insects, even snails. In these species the legs and digits are sometimes slender, but short. Accipiters are rarely crested, but some have very attractive colour patterns. Black phases are present, especially in the tropical species. One in Australia has the only pure white phase. Accipiter is the largest genus in the family, having about fifty species. It is present worldwide, but is especially rich in Papua-New Guinea, where a small island like New Britain may have three to five endemic species or distinct sub-species.
The adult Grey Frog Hawk is clear dark blue to slate coloured above, including the upper side of its tail feathers. The outermost tail feathers are barred with slate and black. The sides of the head and neck are paler grey. The chin and throat are white with black shaft streaks. The upper breast and belly are washed pale rufous on a grey background, sometimes lightly barred with grey. The belly and under-tail coverts are white, the base of thighs grey. The underside of the tail is white at its base, terminating grey with five narrow black bars. The under-wing coverts are pale rufous. The outer primaries are black from below, the inner primaries and secondaries being white with grey tips forming a clearly visible white patch under the wing. The eyes are dark red to brown, the cere and legs yellow. Females are larger than the males but otherwise very similar.
Immature individuals are dark sepia above with pale edges to the feathers; the tail is pale brown with four broad dark bars. Below is white, heavily blotched with dark brown and black with some more rufous barring on the sides. The tail is grey below with four dark bars. The under-wing coverts are pale rufous. The outer primaries are dark brown, the inner primaries and secondaries are grey at the tips and pale pink basally, with dark bars.
Eurasia : East. S Ussuriland and Korea; C & E China and Taiwan. Winters from extreme SE China and Hainan, S through Indochina, Philippines and Indonesia to W New Guinea and occasionally W Micronesia.
Prefers forests and wooded areas near wetlands or paddyfields.
On arriving at the breeding quarters the males repeatedly chase the females, often in small groups of up to seven. The males also perform vigorous undulating displays, the downward dives of a hundred feet or more, much more striking than those of most of the genus. The male feeds the female with frogs during this period. Pairs will later soar together over the breeding ground, with short bursts of wing-flapping interspersed with glides. During display, which lasts about two weeks, the birds are very obvious and noisy, but once nest-building has begun they become silent and more secretive. A new nest is built each year, and is quite quickly constructed. Most building in Korea occurs between 1st and 10th June. Nests are built in small clumps of trees near rice fields or marshes, from six to ten metres from the ground. They are loose structures of twigs lined with fresh green leaves, often chestnut leaves, occasionally sprigs of conifer or pieces of bark, 35 to 45 cm across by 12 cm deep. Fresh leaves are added almost daily during the incubation period Three or four pale bluish grey eggs are laid in early to mid- June. The female only incubates, and is fed on the nest by the male. The eggs hatch about the first week of July, indicating an incubation period of less than 30 days. The young are well grown by mid-July, and are on the wing in August. The whole breeding season is short and concentrated. Adults will defend nests again (human) intruders).
This is a common small sparrowhawk of Korea and Eastern China. During the breeding season it is found in wooded country at low altitudes with swampy ground or rice fields nearby. As it feeds mainly on frogs it hunts for the most part in open ground, either in swamps or rice fields, and does not have to resort to the swift rushes and stealthy surprise tactics of most sparrow hawks. It takes the frogs by short stoops from perches, or from flight. It feeds mainly on frogs, but will take lizards and grasshoppers as well. Scans for prey from perch usually in open country. Catches prey mostly on ground.
Video Chinese Sparrowhawk
copyright: Desmond Allen
Although this species may have a restricted range, it is not believed to approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Almost completely migratory, although sedentary in Taiwan. Some birds winter in South Eeast China, in Guangdong and on Hainan; most move farther South, reaching Indochina, peninsular Malaysia, Philippines, Greater and Lesser Sundas, Sulawesi and West tip of New Guinea. Major migration route through Korea, West Kyushu (Japan) and Ryukyu Islands towards Taiwan; migration detected in September and early October, but not well known in spring. Considerable movement recorded over Bali, where almost 1000 birds seen from early October to early November 1990; movement over North Sulawesi in early March and early October. Birds arrive in Ussuriland in early May.