Quick Answer
The northern goshawk and American goshawk are two similar but distinct species of hawk belonging to the genus Accipiter. The main differences between them are:
- Range – Northern goshawks are found in Eurasia and northwestern North America, while American goshawks are found throughout North America south of Canada.
- Size – Northern goshawks are slightly larger than American goshawks on average.
- Plumage – Northern goshawks have finer barring on their underparts compared to American goshawks.
- Taxonomy – They are considered separate species, A. gentilis (northern) and A. atricapillus (American).
The northern goshawk (Accipiter gentilis) and American goshawk (Accipiter gentilis atricapillus) are large, powerful hawks that are adapted for living in forested areas and taking bird prey. They belong to the widespread Accipiter genus of short-winged, long-tailed hawks.
The northern goshawk has a broad circumpolar distribution across Eurasia and northwestern North America. The American goshawk is native to North America from southern Canada southward. The two were once considered the same species, but are now classified as separate species due to differences in size, appearance, geography, and genetics.
There is still some debate over their taxonomic status, but most authorities now consider A. gentilis and A. atricapillus to be distinct species. This article will go over the key similarities and differences between the northern goshawk and American goshawk in terms of range, physical features, habitat, diet, reproduction, taxonomy, and conservation status.
Range and Distribution
The ranges of the northern and American goshawk do not overlap. The northern goshawk has an extensive range across the northern parts of Eurasia and North America. The American goshawk occupies North America from southern Canada southward through the United States and into Mexico.
Northern Goshawk
The breeding range of the northern goshawk extends throughout boreal and temperate forests across Eurasia. It breeds from western Europe eastward across Russia and northern Asia, south to Mongolia and northern China. In North America, it is found in Canada, Alaska, the western and northeastern U.S, and down along forested mountain chains like the Rockies and Appalachians.
Northern goshawks are mostly permanent residents across their breeding range. Some northern populations may migrate short distances southward in winter.
American Goshawk
The American goshawk occupies a large swath of North America as its breeding range. It is found from southern Canada southward through the conterminous United States. Its range extends throughout many forested areas west of the Great Plains. It is absent as a breeder from the southeastern coastal plain.
American goshawks are generally permanent residents, but may move altitudinally or latitude-wise in winter. Some northern breeders migrate southward in winter, while other populations may wander irregularly in search of food.
Habitat
Both the northern and American goshawks are found predominately in forest environments within their respective ranges. They occur most often in mature coniferous or mixed woodlands and avoid open areas.
Northern Goshawk
In Eurasia, northern goshawks occupy taiga and boreal forests dominated by spruces, firs, pines, larches, and birches. They also utilize temperate forests with oaks, beeches, and other deciduous trees. In North America, they frequent spruce-fir forests, lodgepole pine stands, mixed coniferous woods, and aspen groves.
American Goshawk
American goshawks inhabit a variety of forest types including pine-oak woodlands, mixed deciduous-coniferous forests, aspen stands, and fir or spruce dominated mountain forests. In the western U.S., they are often found in lodgepole pine and ponderosa pine communities. Aspen groves are a particularly important habitat type.
Both species may utilize wooded riparian areas along streams and wetlands within forest settings. American goshawks range further south and can also be found in drier oak savannas and woodlands.
Physical Description
The northern and American goshawks share a typical Accipiter silhouette, with a stout body, short rounded wings, long tail, and short hooked bill. However, there are some subtle physical differences between them:
Size
Northern goshawks are noticeably larger than American goshawks, though their size ranges do overlap. Some key size differences:
- Length: Northern goshawks measure 18-26 inches long. American goshawks measure 17-24 inches.
- Wingspan: Northern goshawks have a wingspan around 40-46 inches. American goshawks have a slightly smaller wingspan of 36-42 inches.
- Weight: Northern goshawks weigh 1.5-3.3 lbs. American goshawks weigh 1.1-2.4 lbs.
The northern goshawk is one of the largest species in the Accipiter genus, while the American goshawk is medium-sized. Females of both species average larger than males.
Plumage
Adults have similar plumage patterns overall – dark slate gray upperparts and pale underparts marked with gray barring. However, the northern goshawk typically shows finer, denser barring on the underside compared to the American goshawk. The American also has a bold white supercilium (eyebrow stripe) which is fainter in the northern.
Juveniles are brownish overall with buffy underparts, which can make young birds harder to distinguish. The difference in underpart barring remains apparent though. The cere (fleshy area around bill) is yellow in adult northern goshawks and greenish in American.
Plumage Feature | Northern Goshawk | American Goshawk |
---|---|---|
Adult Upperparts | Dark gray | Dark gray |
Adult Underparts | Pale with fine gray barring | Pale with coarser gray barring |
Juvenile Plumage | Brown above, buffy below | Brown above, buffy below |
Eyebrow Stripe | Faint whitish | Bold white |
Diet and Hunting
As birds of prey, northern and American goshawks have very similar dietary habits and hunting behaviors. They are powerful, agile hunters specialized for taking fast-moving bird prey through maneuverability in dense forests.
Both species primarily prey on medium-sized birds such as grouse, pigeons, woodpeckers, jays, blackbirds, and passerines. Rabbits, squirrels, and some other small mammals are also taken. Prey is typically captured in dramatic high-speed chases through the forest, utilizing short-distance rapid pursuit flights.
Northern and American goshawks exhibit a degree of variability in terms of prey preferences based on habitat and geographic locations. For example, American goshawks in western forests take more mammals like squirrels and chipmunks compared to eastern birds focused on avian prey. Both may opportunistically hunt small reptiles, amphibians, and large insects as well.
Due to the northern goshawk’s larger size, it can take larger avian prey including some waterfowl, gamebirds, and corvids. But in general the two species have very similar hunting styles and prey profiles overall.
Reproduction
The northern and American goshawks have comparable reproductive biology as large forest-dwelling accipiters:
- They breed in spring, with courtship displays beginning in March/April.
- Monogamous pairs nest solitarily, maintaining breeding territories.
- Large stick nests are built high up in trees, often using old corvid or squirrel nests.
- Females lay 3-4 eggs which are incubated around 30 days.
- Young fledge at 35-45 days old and are dependent on parents into summer.
- Northern goshawks may not breed until 2-3 years old. American goshawks often breed in their second year.
Notable differences:
- American goshawks have a slightly smaller average clutch size of 2-3 eggs.
- The breeding density and territory sizes for American goshawks are smaller than northern counterparts in optimal habitat.
- American goshawks show more variability in nest sites, including shrubs, cavity trees, and cliff ledges.
Overall the two species follow typical Accipiter breeding ecology suited for boreal/temperate forests. The American goshawk exhibits some southern forest adaptations like smaller territories and nest plasticity.
Taxonomy and Classification
The taxonomic status of the northern and American goshawks has been revised over the last several decades:
- They were formerly considered the same species, Accipiter gentilis, with the American goshawk treated as a subspecies, A. g. atricapillus.
- Based on geographic isolation and morphological differences, most authorities split them into separate species in the late 20th century.
- Genetic evidence confirmed distinct lineage divergence, supporting full species status.
- Some experts still question the distinction, but most now recognize them as A. gentilis and A. atricapillus.
- They are sister taxa and each other’s closest relative within the Accipiter genus.
Both are classified in the order Accipitriformes, family Accipitridae. Accipiter is a genus of short-winged forest-dwelling hawks, widely distributed across the world. Overall, the northern and American goshawks are very closely related but distinct species occupying different continents.
Conservation Status
Northern and American goshawk populations face similar conservation threats related to habitat loss, though the American goshawk’s status is more precarious:
Northern Goshawk
The large Eurasian population is still common and the species is classified as Least Concern by the IUCN Red List. Logging and forest clearing have reduced numbers in parts of the range. Some conflict also occurs with gamebird hunting interests.
American Goshawk
This species has declined due to habitat loss and fragmentation across North America. It is listed as Near Threatened and a national Conservation Concern Species. Continued protection of nesting areas and mature forests is critical for recovery.
Sustainable forestry practices that maintain open understory structure and limit disturbance near nest sites can benefit goshawk populations. Both species also face threats from climate change disrupting boreal forests long-term.
Conclusion
In summary, the northern and American goshawks exhibit a suite of similarities and some key differences as large forest-dwelling accipiters occupying separate continents. Their ranges, sizes, plumage details, breeding ecology, and conservation status show notable distinctions that support their status as distinct species rather than subspecies. However, they still share a close evolutionary relationship and fill comparable forest raptor niches in their respective ranges. Continued study and protection of remaining mature forest habitats will benefit both species going forward.