Food Habits

Main Foods Taken

Small aquatic and terrestrial invertebrates, small fish, frogs, and occasionally seeds or berries.

Microhabitat For Foraging

Generally takes prey from water column, feeding by wading in relatively shallow water (Recher 1966). In Missouri, flooded habitats to depth of 7.4 cm ± 0.7 SE (mean 4.2, n = 6; Rundle and Fredrickson 1981); in Saskatchewan, wet meadows and mudflats, or shallow water <10 m from shore, depending on study site (Colwell and Oring 1988); in South Carolina, mean water depth 5 cm ± 0.78 SE (n = 17; Weber and Haig 1996). In Texas, Anderson et al. (1996) found that the pro-portion of feeding birds in flocks was generally highest in intertidal estuarine habitats; these habitats also contained highest densities of birds. Will feed in water up to belly or while swimming (Brooks 1967a, CSE). In coastal Venezuela, feeds primarily when tide is low (Robert et al. 1989). Feeds in vegetation to head height on breeding and wintering grounds (CSE).

Food Capture And Consumption

Appears to forage visually during day, usually taking prey from water column by swift stabs at surface; at night, sidesweeping motions predominate, presumably associated with tactile feeding (Robert and McNeil 1989). Differences in foraging strategy are attributed to high cone and low rod densities in retina, which indicate good diurnal but poor nocturnal vision (Rojas de Azuaje et al. 1993). Feeding strategy unaffected by wind speed, phase of moon, cloudiness, or bioluminescence (McNeil and Robert 1988, Robert and McNeil 1989). Sidesweeping motions used to capture shrimp (Crangon alaskensis) in silt-filled puddles and surface layer of mud on intertidal flats (TLT). Captures fish by running rapidly after them before lunging and submerging head; will repeatedly probe aquatic vegetation until hidden fish are dislodged and can be pursued (TLT). Sometimes captures small fish by running toward surface ripples with bill open and lower jaw submerged; will plow surface in this way for some distance (Rowan 1929, Zusi 1968), sometimes simultaneously with 1–5 conspecifics, which turn in unison (TLT). In contrast, Lesser Yellowlegs rarely feeds on fish.

Occasionally, Greater Yellowlegs feed on insects along shore or snatches them from air. When feeding in water, bill movements consistent with transportation of small items into mouth by combination of surface tension–feeding (sensu Rubega and Obst 1993) and head-throwing, but this needs to be confirmed by filming of birds at close range; larger items transported by head-throwing alone (CSE). Probing rare (T. Randall in Bannerman 1961, CSE). Swallows prey whole. Swallows fish headfirst; manipulates large ones for several minutes, repeatedly dropping and repositioning them (J. T. Nichols in Bent 1927, TLT). In Venezuela, forages as much during day as at night (Robert et al. 1989). In California, prey capture rates marginally higher in seminatural wetlands than in flooded rice fields (CSE).

Few quantitative data. Three birds that Bent (1927) reported on contained 65.3% dragonfly (Odonata) naiads, 22.0% aquatic bugs (Hemiptera: Belostoma sp.), 6.0% fish (Poecilia vivipara) scales, and 0.7% diving beetle (Dytiscidae) larvae. Gobies (Clevelandia ios) taken by birds feeding at coastal California estuaries (Reeder 1951, N. Warnock pers. comm.). Three stomachs taken during fall migration in Illinois contained 60.3% dragonfly naiads (Anax junius, Epicordulia princeps, Erythemis simplicicollis, Plathemis lydia), 16.7% diving beetle adults and larvae (Agabus disintegratus, Hygrotus sp.), 9.7% minnows (Pimephales promelas), 8.3% snails (Physa sp.), 3.3% soldier fly larvae (Odontomyia sp.), 1% seeds, and <1% water boatmen (Corixidae) and earthworms (Lumbricus sp.; Brooks 1967a, 1967b). In Venezuela, 2 birds collected at night contained 90% fish fragments and 45% each of fish and water boatmen respectively (Robert and McNeil 1989). Two birds collected in rice fields in Suriname had eaten spiders (Araneae), beetles (Coleoptera), crickets (Orthoptera: Gryllidae or Gryllotalpidae), and toads (Bufo sp.; Hicklin and Spaans 1993). In central California rice fields, birds take small clams (Bivalvia), snails (Gastropoda), crayfish (Astacoidea), and small fish (CSE). Fall migrants on Alaska Peninsula take sculpins (Cottidae) at coastal sites and salmon (Oncorhynchus sp.) eggs inland. Other foods include ants (Hymenoptera), flies (Diptera), small grasshoppers (Orthoptera), and berries of crowberry (Empetrum nigrum; Bent 1927, Johnsgard 1981). Robert and McNeil (1989) found feathers in the stomach of 1 bird.

Few data from breeding grounds: In Alaska, snails (Littorina sitkana), three-spined stickleback (Gasterosteus aculeatus), adult and larval flies (midges [Chironomidae] and shore flies [Ephydridae]), and occasionally adult dragonflies from salt marsh pools; wood frogs (Rana sylvatica), diving beetles, and whirligig beetles (Gyrinidae) from pools in spruce (Picea spp.) bogs (TLT).

No information on food selection. Not known to store food.

No information.

No information.

Drinks by putting bill in water and tipping head back. Pellet-casting common when feeding primarily on fish, but rarely seen in winter in California, where diet is mostly small invertebrates; usually stands stationary for several minutes before casting, but can resume feeding immediately afterward (TLT, CSE).