Family Sandpipers, Snipes, Phalaropes (Scolopacidae)

Least Concern

Wilson's Snipe (Gallinago delicata)


Taxonomy

French: Bécassine de Wilson German: Wilsonbekassine Spanish: Agachadiza de Wilson
Taxonomy:

Scolopax delicata

Ord

, 1825,

Pennsylvania

.

Until recently considered conspecific with G. gallinago. Morphological differences between the two taxa are slight, one author#R proposing the split “on the basis of differences in winnowing display sounds associated with differences in the outer tail feathers… that are comparable to differences between other closely related species in the genus”. Another author#R noted: “The differences between gallinago and delicata drumming are strong, involve several prominent acoustic characteristics, and are consistent throughout the vast breeding ranges of the two forms” (documentation of this evidence is important to disprove the notion that a circumpolar “ring” effect in sound production might exist). A third#R, however, did not recognize delicata as a species, and cited a limited biochemical analysis by an American team of scientists#R in which the sequence divergence of the two taxa was only 0·6%; subsequently, a European team#R could find no barcode signal to distinguish the taxa. Nevertheless, a recent phylogenetic study#R accepted this split, albeit with little apparent confidence. On balance, species status tentatively accepted here on basis of slower-paced, higher-pitched (more falsetto) drumming (see published sonagrams#R) (3); narrower white trailing edge of wing, and lesser extent of white on the underwing-coverts (2); generally broader dark barring on axillaries (1); generally higher number (4+ vs 2) of dark bars on the outer tail feather (1). Both forms reportedly breed in Aleutians, but this phenomenon remains inadequately documented and would be a fertile area for study. Sometimes also treated as conspecific with G. nigripennis, G. paraguaiae and G. andina, but differences in size, outer tail feathers and quality of aerial “winnowing” suggest separate species status; G. macrodactyla may also be close relative. Monotypic.

What do (1) and (2) mean? Learn more about the scoring system.
Distribution:

Aleutians and Alaska E through Canada to Newfoundland, and S to C California, New Mexico, C Iowa and New Jersey; recently discovered breeding on Chukchi Peninsula, Russia#R. Winters from NW & C USA through Central America and Greater Antilles to N South America.

Descriptive notes

26–28 cm; 79–146 g; wingspan 40–47 cm. Small to medium-sized snipe, with somewhat variable plumage but often colder-looking than G. gallinago; very long, straight,... read more

Voice

“Winnowing” song (drumming) is a tremulous “hu-hu-hu” (higher-pitched than G. gallinago)... read more

Habitat

Open fresh or brackish marshes with rich or tussocky vegetation, bogs, fens, grassy or marshy edges... read more

Food and feeding

Diet mostly larval insects, but also takes crustaceans, earthworms (Oligochaeta) and molluscs; stomachs contain as much as 66% plant... read more

Breeding

Laying early Apr to late Jul. Monogamous, but both sexes show high degree of promiscuity. Territorial; densities up to 15·7 pairs/100 ha in... read more

Movements

Mostly migratory, wintering S to N tropics, where range in N South America rather poorly known, e.g... read more

Status and conservation

Not globally threatened (Least Concern). Total population estimated at two million birds (2005 data). Decline noted in breeding populations of C & E Canada, probably... read more

Recommended citation

del Hoyo, J., Collar, N., Kirwan, G.M. & Sharpe, C.J. (2018). Wilson's Snipe (Gallinago delicata). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/467306 on 22 October 2018).