Identification

Large shorebird with long legs and long, slightly upturned bill. Size quite variable (360–420 mm), with females averaging heavier (246–358 g) than males (196–266 g; Hayman et al. 1986 Hayman, P., J. Marchant, and T. Prater (1986) Shorebirds: an identification guide to the waders of the world. Houghton Mifflin Company, Boston, Massachusetts, USA. Close , Piersma et al. 1996c Piersma, T., J. van Gils and P. Wiersma. (1996c). "Family Scolopacidae (sandpipers, snipes and phalaropes)." In Handbook of the birds of the world. Vol. 3. Hoatzin to auks., edited by J. del Hoyo, A. Elliott and J. Sargatal, 444-533. Barcelona, Spain: Lynx Edicions. Close , J. R. Jehl, Jr., pers. comm.). Also sexually dimorphic in plumage. In Alternate plumage, adult males have dark-reddish underparts with scattered darker barring and blackish upperparts with variable pale spotting. Females paler overall, more mottled above and with less extensive dark rufous below. In both sexes, a white band crosses most caudal portions of upperparts including bases of outer rectrices; a white stripe extends across the wing; and the bill is bicolored, with a pinkish-red base, becoming orange in males during courtship, and dark tip (Sutton 1968b Sutton, G. M. (1968b). Sexual dimorphism in the Hudsonian Godwit. Wilson Bulletin 80:251-252. Close ). Individuals in Basic plumage retain white band on rear upperparts and wing-stripe, but remaining body plumage becomes pale gray-brown with a white belly, white supercilia, and dark lores. Juvenile plumage browner than Basic, with some buff fringing to back feathers and brown-buff below (Hayman et al. 1986 Hayman, P., J. Marchant, and T. Prater (1986) Shorebirds: an identification guide to the waders of the world. Houghton Mifflin Company, Boston, Massachusetts, USA. Close , Paulson 1993 Paulson, D. R. (1993). Shorebirds of the Pacific Northwest. University of Washington Press, Seattle, Washington, USA. Close ).

Size, dark legs, and very long, relatively straight, bicolored bill separate godwits from other shorebirds; snipes and dowitchers superficially similar in appearance, but much smaller. In all plumages, Hudsonian Godwit most easily identified in flight. Combination of white wing-stripe, dark axillaries and underwing coverts, and dark tail with a broad white band at the base is diagnostic (Hayman et al. 1986 Hayman, P., J. Marchant, and T. Prater (1986) Shorebirds: an identification guide to the waders of the world. Houghton Mifflin Company, Boston, Massachusetts, USA. Close ). Black-tailed Godwit (Limosa limosa), a Palearctic species recorded rarely in w. Alaska and casually in e. North America, is similar, but has white wing-linings; a broader, longer, wing-stripe; and a broader white band on the rear upperparts that is at least the breadth of the black tail-band. Larger Marbled Godwit (L. fedoa) is predominantly cinnamon-brown and lacks conspicuous wing-stripe and tail pattern. Bar-tailed Godwit (L. lapponica) also lacks an obvious wing-stripe and a wide black tail-band; race found in Europe (L. l. lapponica) also has more extensive white on tail, with a triangular extension up the lower back and with barring to tail tip, while race found in Alaska (L. l. baueri) lacks extensive white on tail entirely. Feet of Hudsonian Godwit extend well beyond the tail in flight, more like a Black-tailed Godwit than a Bar-tailed (Grieve 1987 Grieve, A. (1987). Hudsonian Godwit: new to the Western Palearctic. British Birds 80:466-473. Close , Higgins and Davies 1996 Higgins, P. J., and S. J. J. F. Davies (editors). (1996). Handbook of Australian, New Zealand & Antarctic birds. Volume 3. Melbourne: Oxford University Press. Close , Eckert 1999a Eckert, C. D. (1999a). A notable movement of godwits in the Yukon, spring 1999. Birder's Journal 8:149-150. Close ).

Standing Hudsonian Godwit is not easily distinguished from Black-tailed and Bar-tailed godwits, and identifications should be made cautiously. In general, however, Hudsonian Godwit looks smaller and darker than these other species. Black-tailed Godwit typically has straighter, less tapered bill and longer legs and neck, which give a taller appearance. European race of Black-tailed Godwit (L. l. limosa) is generally larger than Hudsonian Godwit; Icelandic (L. l. islandica) and Siberian (L. l. melanuroides) races are closer in size, although size varies considerably in all taxa. Male Hudsonian Godwit in Alternate plumage has darker red underparts, especially toward the vent, than does Black-tailed Godwit. Icelandic and Siberian races of Black-tailed Godwit are more similar to Hudsonian, with more extensive red on the underparts than the European race, in which red barely reaches belly (Prater et al. 1977 Prater, A. J., J. H. Marchant, and J. Vuirinen (1977). Guide to the Identification and Aging of Holarctic Waders. British Trust for Ornithology, Tring, United Kingdom. Close , Cramp and Simmons 1983 Cramp, S., and K. E. L. Simmons (1983). The Birds of the Western Palearctic, Volume 3: Waders to Gulls. Oxford University Press, Oxford, UK. Close ). Face and neck of Hudsonian grayer and more contrasting than Black-tailed Godwit, which has orange-red neck, but this feature may be variable, especially in molting birds (Grieve 1987 Grieve, A. (1987). Hudsonian Godwit: new to the Western Palearctic. British Birds 80:466-473. Close ). In Basic plumage, both Hudsonian and Black-tailed godwits have plain-gray upperparts and pale underparts and look very similar. Supercilium of Hudsonian is slightly broader in front of the eye, but reliability of this feature is unclear. Juvenile plumages also similar; but Hudsonian averages duller with more buff on neck and underparts (Higgins and Davies 1996 Higgins, P. J., and S. J. J. F. Davies (editors). (1996). Handbook of Australian, New Zealand & Antarctic birds. Volume 3. Melbourne: Oxford University Press. Close ).

Hudsonian Godwit is closer in shape to Bar-tailed Godwit than to Black-tailed. In Alternate plumage, the red on the underparts of male Hudsonian and Bar-tailed godwits extends to the vent, but Bar-tailed generally has paler red with less distinct barring. Head of Alternate plumage male Hudsonian usually paler than body, unlike Bar-tailed. Females of both species have less red than males, but female Bar-tailed much paler, especially on belly and vent. Upperparts of Alternate Bar-tailed paler and more heavily patterned than Hudsonian. In other plumages, Bar-tailed also tends to be more heavily patterned above than Hudsonian. Facial pattern may also aid identification, although overlap occurs; compared to Bar-tailed, Hudsonian tends to have darker lores and paler supercilia that does not extend far behind the eye (Hayman et al. 1986 Hayman, P., J. Marchant, and T. Prater (1986) Shorebirds: an identification guide to the waders of the world. Houghton Mifflin Company, Boston, Massachusetts, USA. Close , Chandler 1989a Chandler, R. J. (1989a). Mystery photographs. British Birds 82:601-602. Close , Paulson 1993 Paulson, D. R. (1993). Shorebirds of the Pacific Northwest. University of Washington Press, Seattle, Washington, USA. Close ). See also McCaffery and Gill 2001 McCaffery, B., and R. Gill. 2001. Bar-tailed Godwit (Limosa lapponica). In The Birds of North America, No. 581 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA. Close .

In Basic plumage, confusion with Willet (Tringa semipalmata) also possible, but Hudsonian Godwit has longer bill with pink at base and dark legs compared to Willet's heavier, darker bill and blue-gray legs.