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COMMON BLACK HAWK Buteogallus anthracinus 46–53cm, WS 109–
127cm. Fairly large, heavily built hawk of marshes, mangroves, forested and
semi-open areas near water. Perches on roadside wires, bare snags overlooking
water; can be very confiding. Plunges feet first to snatch fish; runs on beaches
and mudflats hunting crabs. Soars regularly, mainly in mid–late morning,
wings flattish, tail spread. Note broad wings, short tail (appreciably longer on
juv.), long yellow legs. Adult has single white tail band, often shows whitish
patch across base of outer primaries. Main confusion risk is Great Black Hawk
(see that species for details). Also cf. perched adult Zone-tailed Hawk; plumage
of juv. Gray and Gray-lined Hawks suggests juv. Common Black but note structure. Attains adult
appearance in 2nd year. Some adults have underside of flight feathers washed rusty. SOUNDS: Often calls
when soaring and in display. Varied series of loud ringing whistles, often intensifying and then fading
quickly: yih yih yih yeep Yeep YEEP YEEP yeep yih-yih-yih and variations. STATUS: Fairly common in coastal
lowlands, especially Pacific mangroves; uncommon and local inland to 750m. (Mexico and sw. US to n.
S America.)
GREAT BLACK HAWK Buteogallus urubitinga 51–61cm, WS 120–137cm.
Large, broad-winged hawk of forested and semi-open areas, marshes,
mangroves. Habits much like Common Black Hawk but rarely seen on ground,
less confiding. Soars with wings flattish, tail rarely spread widely, and often
dangles long legs. Slightly rangier, less compact than Common, with longer
neck, appreciably longer legs, and longer tail that projects noticeably past tail
tip on perched birds (especially juv.); also note voice. Adult Great has less
extensive, often duller yellow at base of bill, coarse white barring on thighs. In
flight, wings of adult Great bulge less strongly on secondaries, feet project past
white tail band; 2nd white tail band of Great hard to see from below but obvious from above, when can
appear as a white tail split by a black band. Juv. Great has paler head than Common, without thick dark
mustache, longer tail has numerous narrow dark bars, broad dark distal band, vs. fewer and broader dark
bars of Common; uppertail coverts mostly white (mostly dark on Common). 2nd-year Great Black
resembles juv. but can show dark mustache and has coarse tail bars, suggesting Common; note structural
differences, mostly white uppertail coverts. Attains adult appearance in 3rd year. Also cf. Crane Hawk.
SOUNDS: High, piercing, drawn-out wailing whistle, perched and in flight from both adult and juv., 2–5
secs. ‘Song’ given in flight carries well: short, overslurred piping whistles in prolonged rapid series, whi’
pih-pih-pih.…STATUS: Uncommon on both slopes, locally to 1800m. (Mexico to S America.)
[SOLITARY EAGLE] Buteogallus solitarius 64–79cm, WS 152–188cm. No unequivocally documented
record from Costa Rica, and perhaps does not occur in the country. Included here to facilitate confirmation
of potential occurrence. Very large hawk of humid forest and edge, most likely in foothills. Soars mainly
in mid–late morning. Adult from smaller Common Black Hawk (which can appear disconcertingly large
thanks to its shape and slow wingbeats) by paler, slaty-gray plumage, relatively shorter tail, and thicker
legs; in flight, toes project almost to tail tip, vs. projecting just into white tail band on Common Black. Juv.
has distinctive plumage, with large dark patches at sides of breast, dark thighs, and overall plain underside
to flight feathers, with no distinct tail bars. 2nd-year resembles adult but browner overall, with sparse buff
streaks on head, body, underwing coverts; tail pattern like adult but broad median band pale gray, not
white. Probably attains adult appearance in 3rd year. Also cf. Great Black Hawk. SOUNDS: Melancholy
drawn-out whistle, 1–2 secs, lower and less piercing than Great Black Hawk. In flight, powerful whistled
screams in slightly speeding and slowing series, whieh-whieh..., cadence reminiscent of Common Black
Hawk but notes stronger, lower-pitched. STATUS: Uncertain. Has been reported from Caribbean slope and
s. Pacific slope, mainly in foothills. (Mexico locally to S America.)