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ROADSIDE HAWK  Rupornis magnirostris 33–41cm, WS 68–79cm. Small

lowland hawk of open and semi-open country; often perches on roadside wires,

fence posts. Flight mostly low with rapid stiff wingbeats, brief glides. Soars on

flattish wings; display flight of fluttering wingbeats interspersed with glides on

wings held in a strong V. Adult distinctive, with staring pale eyes, grayish head

and breast, rusty-barred belly; rusty wing panels in flight; pale tail bands grayish

to rusty. 1st-year has distinctive streaked breast but barred belly, broad pale tail

bands, cf. Broad-winged Hawk. SOUNDS:  Nasal, complaining, overall

descending scream, meeahh, about 1 sec; ‘song’ (mainly in display flight, less

often from perch) an often persistent, fairly rapid series of clipped nasal yaps, intensifying and fading,

heh-heh-heh..., can suggest Lineated Woodpecker. STATUS: Fairly common to uncommon on both slopes,

to 1500m. (Mexico to S America.)

GRAY HAWK  Buteo [nitidus] plagiatus 42–46cm, WS 81–94cm. Medium-size

hawk of forest and edge, semi-open habitats. Commonly perches on roadside

wires, utility poles. Soars frequently, wings held flattish and tail usually slightly

spread; often in mid–late morning kettles with vultures and other hawks. Adult

distinctive in most of range, with pearly gray plumage barred below, brown

eyes, black-and-white tail bands; cf. Gray-lined Hawk which overlaps locally on

cen. Pacific slope (see under that species). 1st-year Gray from most species by

size, shape, habits; whitish face with bold dark eyestripe and mustache; also

note fairly long tail with pale bands typically slightly wavy and progressively

wider toward tip, dusky barring on thighs. In flight, often appears uniformly pale below without distinct

dark trailing edge to underwing of 1st-year Broad-winged Hawk. Cf. 1st-year Gray-lined, Common

Black, and Broad-winged Hawks. SOUNDS: Adult has drawn-out, overall descending scream, whéeeeeu,

1–1.5 secs, not as hoarse as Roadside Hawk. ‘Song’ a series of inflected mournful whistles, often around

or before dawn, typically 3–10×, h’wheeeu, h’wheeeu.…STATUS: Fairly common to uncommon on both

slopes, to 1600m. (Mexico and sw. US to w. Panama.)

GRAY-LINED HAWK  Buteo nitidus 41–45cm, WS 80–92cm. Habitat and

habits like Gray Hawk, which Gray-lined replaces on s. Pacific slope. Adult

averages paler than Gray, with more distinct dark barring above, broader white

tail bands, but some very similar to Gray; in flight, note lack of dark trailing

edge to wings, more distinct dark barring on underside of primaries. 1st-year

from Gray Hawk by sparser dark blotching below concentrated on breast sides

and flanks, plain pale buffy thighs; averages fewer and broader dark tail bars. Cf.

1st-year Common Black and Broad-winged Hawks. SOUNDS: Adult has overall

descending scream, whéeeu, 0.5–1 secs, usually higher, more abrupt, and more

sharply descending than Gray Hawk. ‘Song’ a series of inflected mournful whistles, up to 10× or so,

huwéoo huwéoo..., more strongly inflected than Gray. STATUS: Uncommon to fairly common on s. Pacific

slope, to 1200m. (Costa Rica to S America.)

BROAD-WINGED HAWK  Buteo platypterus 38–43cm, WS 82–92cm. Winter

migrant to forest and edge, woodland, plantations; transient migrants occur

widely. often streaming overhead with Swainson’s Hawks and Turkey Vultures.

Wintering birds mainly in subcanopy, on roadside wires. In flight note relatively

tapered wings, evenly pale flight feathers (primary panel translucent when

backlit) with dark trailing edge; adult has single broad whitish tail band. At rest,

note long wings extending well down tail. 1st-year has variable dark streaking

below, dark spots (not bars) on thighs, cf. Gray and Gray-lined Hawks. Rare

dark morph (all ages) solidly blackish brown body and underwing coverts, cf.

dark Short-tailed Hawk. SOUNDS: High, thin, slightly tinny scream ssiiiiiiu, about 1 sec, from perch and

in flight. STATUS: Common transient on both slopes and through highlands, late Sep–Nov, Mar to mid-

May; fairly common to common in winter on both slopes, especially foothills and mainly below 2000m.

(Breeds N America, winters Mexico to S America.)