We used banding data to investigate dispersal and survival of Red-shouldered Hawks (Buteo lineatus) in two study areas in southern Ohio from 1996 to 2018. Of the 2448 nestlings we banded, 167 (6.8%) were encountered (dead or alive) some time after banding. Mean distance from the natal nest at the time of encounter was 31.6 6 6.2 km (median ¼ 10.0, range ¼ 0.1-568.6 km, n ¼ 163); natal dispersal distance averaged 16.0 6 1.9 km (median ¼ 9.0, range ¼ 1.4-117.1 km, n ¼ 110), and was significantly greater for females than for males. Most hawks dispersed ,30 km, but 11 hawks (6.7%) dispersed .100 km from their natal nest. Of these long-distance dispersers, nine (82%) were ,2 yr old, suggesting that some young birds wander widely prior to breeding. Dispersal distance differed by sex and age at encounter, with dispersal distance negatively correlated with age at encounter, and females dispersing farther (39.8 6 12.3 km) than males (22.8 6 9.86 km) and unknown-sex birds (33.9 6 10.6 km; all P , 0.05; means estimated from the logistical regression model). Dispersal direction for all birds followed a uniform distribution (P. 0.05); however, dispersal direction of long-distance dispersers was not uniform (P , 0.05) but bimodal, with hawks encountered either to the south or to the northeast of the study area. Mean age at recovery was 2.6 6 0.3 yr (median ¼ 1.5 yr, range ¼ 0.2-10.3 yr). As in other raptor species, apparent annual survival varied between age classes, with young birds (hatch-year and second-year) having lower apparent annual survival (0.49 6 0.03) than adult birds (0.76 6 0.03). Our study provides information on dispersal, survival, and causes of mortality of Red-shouldered Hawks, demographic data that are important for evaluating population trends and the sustainability of urban/suburban populations.
The red-shouldered hawk is a crow-sized buteo, or soaring hawk. The adults are strikingly plumed, with rufous (brownish red) shoulder patches and a rufous barred breast. Rufous lesser and median upperwing coverts form the "red shoulders" evident on this species. The flight feathers of adults are barred black and white and show a white crescent-shaped window across the primaries, which is visible in flight. The underparts, which are rufous with white barring, often exhibit thin, dark streaks on the chest. The head and back are dark brown. The black tail is bisected by several narrow white bands. Although females average slightly larger than males, plumage is similar for both sexes. The call of the red-shouldered hawk is a series of nasal drawn-out "aahhh" cries. Juvenile red-shouldered hawks can be distinguished from adults by their overall browner, less brilliant plumage. The shoulder patches of juveniles are paler rufous and the crescents across the primaries are tawny. The underparts are whitish with variable amounts of brown streaking. The tail is brown with several thin pale bands. Adult plumage appears in the second year. The red-shouldered hawk is a long-tailed buteo with squared-off wings and a protruding head. Characterized by quick choppy wingbeats interspersed with short glides, the flight style of this hawk is similar to that of an accipiter. When soaring, most buteos hold their wings straight out, whereas the red-shouldered hawk bows its wings forward.
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