The Northern Goshawk (hereafter referred to as Goshawk) is a large forest raptor, occupying boreal and temperate forests throughout the Holarctic. In North America, it breeds from Alaska to Newfoundland and south (Figure 1). This partial migrant winters throughout its breeding range including occasionally the Great Plains and southeastern states; some individuals undergo short movements to lower elevations during winter, apparently in search of food. Irruptive movements of northern birds to the south occurs at approximately 10-year intervals that coincide with population lows of snowshoe hare (Lepus americanus) and grouse.
Largest of the three North American accipiters, the Goshawk is a powerful hunter capable of killing a variety of prey, including tree squirrels, hares, grouse, corvids, woodpeckers and large passerines such as American Robins (Turdus migratorius). When breeding, the female generally defends the nest while the smaller male provisions the family with food. Foraging males rapidly traverse large home ranges when searching for prey. Goshawks are well adapted for hunting in forests but also hunt open habitats. They are short duration sit-and-wait predators, perching briefly while searching for prey before changing perches. Their short, powerful wings allow rapid acceleration and their long tails quick maneuverability in trees. As an aggressive North American hunting hawk, Goshawks eagerly crash through brush when capturing prey or readily strike intruders approaching their nests.
Although Goshawks nest in a variety of habitat types—from willow stands along Arctic rivers to massive old-growth forests of the Pacific Northwest—they seem to prefer mature forests with large trees on moderate slopes with open understories. They nest in either coniferous, deciduous, or mixed-pine forests, depending on availability. Nest trees are usually one of the largest trees in the nest area; most territories contain several alternative nest trees.
Whether carried afield on the fists of Japanese shoguns or by medieval falconers of Europe, Goshawks have seen much human history. Revered as symbols of strength, a Goshawk adorned the helmet of Attila the Hun. The courage and extreme aggression of this species when hunting grouse, ducks, rabbits, and hares helped gain its reputation as the “cook's hawk” among falconers. However, reverence changed to persecution when guns replaced trained hawks as the preferred means of providing game. Currently, the species is not listed as Endangered in U.S. but there is concern that timber harvest and human encroachment are reducing some populations.
Since the early 1970s, research has resulted from concerns about the effects of forest management on populations ( Reynolds et al. 1982 , Moore and Henny 1983 , Reynolds 1983 ). Crocker-Bedford's ( Crocker-Bedford 1990 ) contention that populations in the Southwest were dropping precipitously catalyzed additional research by state and federal agencies. Most research in North America has discussed habitat-use patterns, home-range characteristics, food habits, productivity, and demography. European studies provide insights regarding migration, winter biology, behavior, and predator–prey relationships.