1	Forensic Identification An Immature Raptor ID Challenge Connie Goldman
2	History A raptor was received at ACNATSCI for addition to the collection Had been found dead in Cape May New Jersey in November Characteristic field marks of an immature hawk Appearance fairly bulky
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6	Data Weight 485 gm; general impression suggested accipiter or possible buteo Sex - male Bare Parts – Bill dark brown tip to yellow at base; tarsi yellow-green; irides pale yellow Molt – none in wings, tail or body Bursa – none
7	Mass of our bird = 485gm Sharp-shinned 150 - 218gm Broad-winged Hawk 265 - 560gm Cooper’s Hawk 450gm Red-shouldered Hawk 550 - 750gm Goshawk 630-1099gm
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10	Is it a Cooper’s Hawk? Weight is significantly higher than expected Supercilium, described as white, or pale indistinct Ventral streaking narrow; ground color of underparts pale buff to nearly white.
11	Cooper’s Hawk? Underside of wings with narrow dark brown bars or elongated streaks White spots or patches on scapulars and inner secondaries Banded tail – underside of tail with 5-6 dark transverse bars.
12	What about Northern Goshawk? Weight is significantly lower than expected; No distinct bar across wing, body should be lighter than other accipiters (one ref. says darker) Upper parts with white and cinnamon markings Ventral streaking extends to undertail
13	Northern Goshawk? Only goshawk description mentions the color green for tarsi Wing with relatively straight leading edge, s-curve on trailing edge. Tail bands appear wavy, bars edged in thin white
14	Broad-winged Hawk? Size right; body chunky, stubby White markings throughout upper parts Buteo with fairly pointed wing Suggestion of a dusky trailing edge to underwing; immatures can have some barring on underwing
15	Broad-winged Hawk? Ventral streaking – “highly variable” “some juveniles show more or less uniform streaking below” Superciliary line present in immatures Banded tail – juvenile tail when closed is long, narrow; juvenile tail longer than adult; tail tipped in white
16	Reasons BWH was rejected Plumage - ventral streaking commonly concentrated on sides, across belly Tail – broad dark subterminal band on tail; tails band width, number Wing – underwings clean, white; dusky bar along trailing edge giving “framed” appearance to underwing; shape of wing
17	Reasons Cooper’s was rejected Size smaller than our specimen Streaking does not extend to undertail Supercilium less prominent Tail should be longer in comparison to body Tail bars should align
18	Final Identification Northern Goshawk In spite of low weight, proportions were acceptable Plumage not completely consistent with expectations, no distinct “light bar” or “tawny streak” across wing Ventral streaking thinner than seen in some birds, but streaks do extend down to undertail Bold superciliary line Wing shape and pattern as expected; virtually straight (no bend at ‘wrist’) leading edge, curved trailing edge Green tone in tarsi Wide tail bands, wavy, thin white rim to each, zig-zag when spread
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20	References Birds of North America Sibley, D. 2000,The Sibley Guide to Birds Bent’s Life Histories on line USGS Patuxent WildlifeResearch Center HMANA Eastern Raptor Migrant Guide Hanging Rock Raptor Observatory, W. VA Dunne, P. Sibley, D., Sutton, C. 1988, Hawks in Flight