The Broad-winged Hawk is a migratory raptor that comes through Vermont in large numbers in the fall, on the way to its wintering grounds in Central and South America. They also breeds here, and their sharp whistle is often heard in the summer. Easily identifiable in flight by their broad white and black stripes on the tail, they can often be confused with the Red-shouldered Hawk, a larger, scarcer cousin here.
The Broad-winged Hawk has six subspecies. Five of them are endemic to the Caribbean; the one subspecies commonly seen here is the nominate Buteo platypterus platypterus.
Birds of the World (Goodrich et al. 2020) says:
Subspecies are diagnosed on the basis of body size, extent of rufous edges to the head feathers and wing coverts, density of ventral barring, thigh color and pattern, and overall color saturation. Differences among some described insular forms are unclear (see Friedman 1950, Palmer 1988) or perhaps insufficient (e.g., B. p. rivierei, fide Hellmayr and Conover 1949:117); a comprehensive analysis is needed.
B. p. platypterus (Vieillot, 1823). Precludes Falco latissimus Ord, 1815 (a nomen nudum) and includes F. wilsonii Bonaparte, 1824; F. speciosus Voight, 1831; and B. p. iowensis Bailey, 1917. Breeds east for the Rocky Mts. from ne. British Columbia east to the Maritimes and south, chiefly east of the Great Plains, to the Gulf of Mexico (from e. Texas to n. Florida), with isolated pockets in the Black Hills region and at scattered locales on the central and e. Great Plains [type locality = near the Schuylkill River, Pennsylvania]; winters in tropical highlands from s. Mexico south to w. Brazil, e. Peru, and n. Bolivia. Large (male wing > 260 mm, female wing > 275 mm); feathers on crown, nape, and wing coverts narrowly edge with dull rufous; dorsum medium brown; ventral bars approximately even white and rufous; throat mostly unmarked white; thighs buff and moderately barred.
Pyle (1997) writes:
Large but with proportionally small bill ... dimorphic (vs solely light morphs in W.Indian subspecies); upperparts with little or not rufous (vs with broader rufous fringing); throat primarily whitish (vs primarily dark); underparts of AHY/ASYs whitish and pale rufous (vs buffy or tawny with darker rufous markings in W.Indian subspecies).
Here in Vermont, the dark morph is considerably rarer than out west. Any dark-morph can be safely identifed to the subspecies level. However, the five Caribbean subspecies could possibly be lumped into a single subspecies; both Birds of the World and Pyle note that more research is needed. This, combined with the little differentiators for those subspecies, means that there aren't clear indicators that can be used to differentiate the northern subspecies from the southern subspecies except range.
For instance, although Goodrich et al. (2020) note above that subspecies are possible to be diagnosed on those features above, they also write this:
B. p. insulicola Riley, 1908. Resident on Antigua type locality = Antigua. Like B. p. platypterus, but small (male wing < 260 mm, female wing < 275 mm) and paler overall.
B. p. rivierei Verrill, 1905. Resident on Dominica, Martinique, and St. Lucia type locality = Dominica. Like B. p. insulicola, but darker and with the throat streaked.
If insulicola is only paler and smaller, than their paragraph that the birds can be differentiated based on a variety of features doesn't make sense. As well, if rivierei is darker than insulicola, does that make it the same as platypterus? There are some Broad-wing Hawks that can appear to have streaked throats in the northern subspecies (see this bird, for instance). What does that mean for rivierei?
In short, this bird is not easily identifiable down to the subspecies level. Instead, range could be the only indication (excepting the dark morph). While platypterus occasionally passes over the lesser Antilles (Goodrich et al. 2020), the endemic species there don't appear to move north. Any bird seen in Vermont will almost certainly be the platypterus subspecies.
To date, there are few records of other subspecies in Vermont. The record listed when this page was created was the first record of the Northern Broad-winged Hawk in Washington County, Vermont.
Nomenclature:
Salient identification points:
Example Records:
Local subspecies records:
Needs:
These needs reflect eBird's database, and whether the bird has photos, audio, or sightings in a given area. "None" denotes that this species has been satisfactorily documented.