Scientific Name: Buteo lineatus
Taxonomy Group: Birds
Range: Ontario, Quebec, New Brunswick
Last COSEWIC Assessment: April 2006
Last COSEWIC Designation: Not at Risk
SARA Status: Schedule 3, Special Concern - (SARA Schedule 1 provisions do not apply)
Image of Red-shouldered Hawk
The hawk is a large raptor, 40 to 61 cm in length with a 1 m wing span. Females are larger than the males, but have similar colouring. The upper parts are mainly brown, and the shoulders are reddish. The breast and belly are barred white and reddish-brown. The tail is blackish with narrow white bars on adults. Immature birds are more uniformly brown with streaked underparts, and attain adult plumage after 18 months. The species is often confused with stockier and larger Red-tailed Hawk, though that species has a solid reddish tail in place of the Red-shouldered Hawk's barred black and white tail. The adult Broad-winged Hawk is also similar but smaller, with much broader white bars across its tail.
Distribution and Population
The Red-shouldered Hawk was the most common diurnal (active in daytime) raptor to breed in the deciduous forests of eastern North America before dramatic declines in the late 1950s through 1970. Since 1970, populations have either stabilized or increased. The Canadian population is now estimated at 2000 to 5000 pairs. The North American breeding range extends south from Michigan, Ontario, Quebec and New Brunswick to central Mexico and the Gulf of Mexico region of the United States. One subspecies breeds only in coastal California. In Canada, Red-shouldered Hawks breeds in southern Ontario, southwestern Quebec and occasionally in New Brunswick. Most winter in the eastern and southern United States, however, if the food supply is adequate, some may remain in southern Ontario and Quebec.
The bird prefers deciduous or mixed-wood forests containing shade-tolerant hardwood trees close to wetland areas. Hardwood forests covering eastern North America were gradually cut or cleared during European settlement. Quantity and quality of forested habitat declined dramatically. Forest regeneration of recent decades has created new habitat. Large woodlots (10 to 100 hectares) can sustain viable Red-shouldered Hawk populations provided larger raptors do not interfere.
The bird breeds in Canada in late March or early April. It begins breeding at two years of age. Courtship displays include flying, soaring and diving. The species constructs bulky stick-nests lined with bark, leaves and lichens, halfway up large, mature trees. Trees usually have straight trunks and few lower branches. The beech is a favoured nesting tree in Ontario. The hawk rarely leaves the woods surrounding its nesting site during breeding season. It is a monogomous species. Females lay one clutch, of two to four eggs, annually, at two to three day intervals, usually in mid to late April. The eggs are dull-white, sometimes marked with brown. Incubation is shared. Hatching occurs in 28 to 33 days. The young fledge about 45 days after hatching. About 41 % survive their first year. 70 % survive each subsequent year. Their diet consists mainly of mammals, reptiles and amphibians. The species is characterized by its shy, secretive, passive nature. It is also known for its habit of returning to the same breeding site year after year. Fall migration occurs from mid-October to early November.
Habitat loss impacts heavily on Red-shouldered Hawks. Destruction of huge expanses of timberland has severely limited suitable habitat, hence population sizes. Forest cutting and filling in of wetlands has diminished the numbers of available prey. Competition from Red-tailed Hawks and Great Horned Owls prohibits nesting in smaller woodlots. Both competitors are more able than the Red-shouldered Hawk to withstand the changing environmental conditions. Since the Red-tailed Hawk mates earlier in the season, it often usurps nesting sites previously established by a Red-shouldered Hawk. Humans have shot the bird, destroyed its nests and killed hatchlings. Effects of chemical poisoning are uncertain. Eggshell thinning and premature breakage have been reported.
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
3 record(s) found.
- COSEWIC Status Reports (1 record(s) found.)
- COSEWIC Assessments (1 record(s) found.)
- COSEWIC Annual Reports (1 record(s) found.)
COSEWIC Status Reports
COSEWIC Annual Reports
COSEWIC Annual Report - 2006 (2006)2006 Annual Report to the The Minister of the Environment and the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.
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