The red-shouldered hawk is a characteristic raptor of eastern woodlands. They get their name from the rufous coloration on the leading edge of their wings, which are otherwise checkered with black and white. The scientific name, Buteo lineatus, refers to the black and white striping on its tail.
The harsh, insistently-repeated territorial calls of red-shouldered hawks are easily recognizable. Listen to a sample here. Be careful, though, not to be tricked by a blue jay. Blue jays frequently mimic the calls of red-shouldered and other hawks. In breeding season such mimicry may cause other songbirds to vacate their nests, leaving the eggs open to predation by blue jays.
Unlike red-tailed hawks, which seem able to thrive in any habitat, red-shouldered hawks have a strong preference for mature woodland near streams and wetlands. Their diet is heavy in reptiles and amphibians, characteristic wetland animals, though they will also take small mammals.
The population of red-shouldered hawks has declined considerably over the past century, due to pesticides and habitat loss. While numbers have improved somewhat since the banning of DDT, the loss and degradation of habitat continues to be a threat.
You can see more pictures of this beautiful hawk at the Canadian Peregrine Foundation.