SPECIES

Bar-tailed Godwit Limosa lapponica Scientific name definitions

Brian J. McCaffery and Robert E. Gill
Version: 1.0 — Published March 4, 2020

Breeding

Phenology

Pair Formation

May occur prior to arrival on breeding grounds (see Behavior: sexual behavior, above). Paired courtship flight on 23 Jun on Yukon-Kuskokwim Delta may have been pair preparing to renest (BJM).

Nest-Building

Scrape displays by both sexes early in breeding season (see Behavior: sexual behavior, above).

First/Only Brood Per Season

Figure 3 . In Alaska, earliest clutches started by 19–20 May on coastal Yukon-Kuskokwim Delta (Kessel 1989), fourth week of May on Seward Peninsula and in Andreafsky Wilderness (Kessel 1989, BJM), and second week of Jun in n. Alaska (where late viable clutch taken on 23 Jul; Bailey 1948). Egg-laying in first week of Jun in Norway (Byrkjedal et al. 1989); first clutches as late as third week of Jun in Taimyr (>73°N; Yésou et al. 1992).

Hatching starts end of second week of Jun on Yukon-Kuskokwim Delta, peaks during last week of Jun and first week of Jul on Seward Peninsula (Kessel 1989), starts first week of Jul in n. Alaska (Bailey 1948) and last week of Jun in Norway (Byrkjedal et al. 1989).

Second/Later Brood Per Season

Never 2 broods, but may replace first clutch (Brandt 1942). In Taimyr, banded male with full second clutch (of unknown maternity) found 10 d after first clutch collected (Yésou et al. 1992); these 2 clutches more similar than any other pair of clutches at site (n = 5), suggesting same female may have laid both (contra Yésou et al. 1992).

Nest Site

Selection Process

Both sexes Nest-Scrape (see Behavior: sexual behavior, above), but no information on selection of ultimate nest site.

Microhabitat

Variable. Frequently a slightly elevated ridge generally drier than surrounding vegetation (Brandt 1942, Cramp and Simmons 1983); rarely dry, lichen-covered summit ridge (J. Dorio pers. comm.). Also found in poorly drained meadows with little microtopography (C. Harwood pers. comm.) and wet basins surrounded by tussock tundra (Cotter and Andres 2000, P. Martin pers. comm.). On outer Yukon-Kuskokwim Delta, among 35 nests, 17 in grass meadows; 8 on uplands; 3 each on slough banks, shorelines, and peninsulas; and 1 on small island (T. Bowman pers. comm.); searching not stratified by habitat and search intensity may not have been comparable among habitat types (i.e., data do not address habitat selection per se). In Norway, nests found in humid cottongrass bogs, scrubby peat bogs, flat palsa bogs with crowberry and open dwarf birch, and rich lichen-dominated heath (Larsen and Moldsvor 1992). In Siberia, on dry hummocks covered with sedge, moss, and dwarf shrubs within 1.5 m of wet depressions (Yésou et al. 1992). For information on nest location relative to other species, see also Behavior: predation, above.

Site Characteristics

Frequently well concealed by standing vegetation (sedge and/or dwarf shrub, including Ledum decumbens), and placed near or between tussocks (Nelson 1887a, Brandt 1942). Alternatively, may be in open without overhead coverage (Figure 4), frequently in meadows dominated by nontussock sedges (C. Harwood pers. comm., BJM).

Nest

Construction Process

As in other Limosa, probably by both parents (Cramp and Simmons 1983). Lining added to nest during egg-laying (Brandt 1942).

Structure And Composition Matter

Usually simple scrape or depression in tundra vegetation, but occasionally includes woven sedges (Brandt 1942). Nest-lining includes lichens, dead leaves (graminoid, willow, ericads), dry root fibers, and moss (Nelson 1887a, Brandt 1942, Bailey 1948, Yésou et al. 1992).

Dimensions

Outside diameter, no information. From 12 nests on Yukon-Kuskokwim Delta, inside diameter 15.2–17.8 cm; depth 7.6–10.2 cm (Brandt 1942). In 5 nests from Taimyr, (presumably) inside diameter 14–16 cm; depth 3–5 cm (Yésou et al. 1992); 7 nests from Yamal Peninsula, inside diameter 13.0–15.5 cm, depth 4.0–5.5 cm (Danilov et al. 1984).

Microclimate

No information.

Maintenance Or Reuse Of Nests, Alternate Nests

No information.

Nonbreeding Nests

Male may make multiple scrapes; not known which, if any, of display scrapes selected as nest.

Eggs

Shape

Variously described as pointed oval to pyriform (Cramp and Simmons 1983), and subpyriform to ovate pyriform, usually the latter; exceptionally, elongate ovate (Brandt 1942).

Size

L. l. baueri from Yukon-Kuskokwim Delta (Brandt 1942): mean length 55.1 mm (range 50.5–60.5, n = 80); mean breadth 38.1 mm (range 36.1–40.6). From Eurasia on Yamal Peninsula (Danilov et al. 1984): length 49.9–55.2 mm, breadth 34.5–38.8 mm (n = 12); on Taimyr Peninsula (Yésou et al. 1992): mean length 53.8 mm ± 2.40 SD (range 51.6–58.1, n = 19), mean breadth 36.8 mm ± 0.89 SD (range 35.7–38.3, n = 19); and at Chaun Bay, Siberia (Kondratiev 1982): length 52.8–57.8, breadth 35.8–37.2 (n = 8).

Mass

Calculated mass 37 g; equals 11% mass of nesting females in Scandinavia (Cramp and Simmons 1983).

Color

Following from Brandt 1942 . On Yukon-Kuskokwim Delta, ground color usually greenish (serpentine green and dull citrine to yellowish glaucous); rarely, snuff brown. Surface markings variable in size, color, and extent, occasionally absent. When markings present, frequently sparse and widely dispersed with irregular to elongated shape, but occasionally large and forming dense patch on rounded end of egg. Color of surface markings various shades of brown to brownish olive; latter particularly if ground color quite green. Underlying markings usually faint, generally grayish, but often numerous and large. Additional sparse grayishblack flecks on some eggs. In Eurasia, green to olive, with variable, mainly small spots, blotches, and speckles of dark brown and gray (Cramp and Simmons 1983).

Surface Texture

Smooth and slightly granular, usually with slight luster; latter occasionally lacking (Brandt 1942).

Eggshell Thickness

No information.

Clutch Size

Median and mode 4, range 2–5 (Brandt 1942, Kessel 1989, T. Bowman pers. comm.). See Demography and populations: measures of breeding activity, below.

Egg-Laying

Yolk formation 8–12 d in Bar-tailed Godwits on Yukon-Kuskokwim Delta (Roudybush et al. 1979). Little information on duration or timing of laying. Probable mate-guarding may extend beyond clutch completion (see Incubation, below). May replace clutch if lost to predator (Brandt 1942).

Five-egg clutch reported twice (Brandt 1942, C. Ely pers. comm.); in both nests not known if all eggs laid by same female. One instance of interspecific nest piracy. Female godwit laid 4-egg clutch on top of 5-egg Willow Ptarmigan (Lagopus lagopus) clutch; godwit abandoned nest within week (Brandt 1942).

Incubation

Onset Of Broodiness And Incubation In Relation To Laying

No information.

Incubation Patches

Both sexes with 2 large, elliptical incubation patches, 1 on each side of midline, which likely develop at onset of incubation (REG). Not known when patches recede in either successful or failed-nesting adults.

Incubation Period

Twenty to 21 d (Cramp and Simmons 1983).

Parental Behavior

Both birds incubate (Conover 1926, Brandt 1942, Yésou et al. 1992); either male (H. Witherby in Cramp and Simmons 1983) or female (Yésou et al. 1992) may take major share. On Yukon-Kuskokwim Delta, closest sitter of any incubating shorebird (Brandt 1942). Atypically, male left 4-egg clutch to chase off second male courting incubator's mate >100 m from nest, then participated in courtship flight with mate before returning to nest (BJM).

Incubation Rhythms

Reportedly male during day and female at night (Piersma et al. 1996c). On Yukon-Kuskokwim Delta, however, females regularly found incubating during day (Brandt 1942); more recent observation found either sex may act as sentinel during daylight hours (BJM). In Taimyr, male contribution to incubation greatest during first week after laying, then apparently declines (Yésou et al. 1992).

Changeover Activities

Little information. In western Palearctic, female relieved from nest flew immediately to attack-mob Hooded Crow (Corvus corone; Cramp and Simmons 1983).

Hardiness Of Eggs Against Temperature Stress; Effect Of Neglect

No information.

Hatching

Preliminary Events And Vocalizations

No information.

Shell-Breaking And Emergence

No information.

Parental Assistance And Disposal Of Eggshells

No information.

Young Birds

Condition At Hatching

Nidifugous, ptilopaedic young grow rapidly. Plumage and bare parts described under Appearance, below. Chicks in brood of 4 at hatch ranged from 27.5 to 28.4 g (Kondratiev 1982).

Departure From Nest

Precocial, but little detailed information (Cramp and Simmons 1983). Presumably similar to Hudsonian and Marbled godwits, in which young leave nest within 1–2 d of hatch and are able to run, swim, and catch insects within 48 h (Baicich and Harrison 1997, Gratto-Trevor 2000).

Growth And Development

Little information. Completely downy chick estimated to be 5 d old weighed 40.2 g (Kessel 1989). Chicks fly at 28–30 d (Kessel 1989, Piersma et al. 1996b).

Parental Care

Brooding

No information, but both parents accompany young (see also Behavior: predation, above), or possibly just male. Adults depart soon after young are able to fly.

Feeding

As in most other shorebirds, presumably does not feed young.

Brood-Rearing Habitat

Often differs from nesting habitat. Adults may move chicks several kilometers from nest within 1 wk of hatching (Larsen and Moldsvor 1992). In Alaska, broods moved to areas with low to medium willow thickets (≤2 m high, often riparian), extreme microtopographic relief (e.g., hummocks ≤1 m high), and/or wetlands (White and Boyce 1978, Kessel 1989, T. Pogson unpubl., T. Swem pers. comm., BJM). Older broods often move to open habitats on high ridges and saddles to join intraspecific and interspecific brood aggregations (Lanctot et al. 1995, REG; see Behavior: predation, above).

Cooperative Breeding

No information.

Brood Parasitism by Other Species

No information.

Fledgling Stage

Departure From Nest

See Young birds, above.

Growth

No information.

Association With Parents

Adults usually depart soon after young fledge (Piersma et al. 1996c), but exceptions. Adults may remain with young (and continue attack-mobbing predators) after fledging (Conover 1926, Gabrielson and Lincoln 1959, C. Harwood pers. comm., BJM); ratio of young to adults (up to 10:2) in some brood aggregations on Seward Peninsula, AK (Lanctot et al. 1995), indicates adults may also abandon young at or shortly before fledging.

Immature Stage

Juveniles independent (and on coastal staging areas) as of late Jul on Seward Peninsula and Yukon-Kuskokwim Delta (Kessel 1989, Gill and Handel 1990); by first week of Aug in nw. Alaska (Bailey 1948). Not known if some immatures travel to coastal staging areas with parents. On staging grounds, often in age-specific flocks (BJM, REG; see Behavior: self-maintenance, above). Juveniles made up <3% of population at site on Yukon-Kuskokwim Delta during peak of staging in Sep 1999 (McCaffery and Gill 1999). In New Zealand, among 50-bird samples scanned at 4 major roosting sites in Oct, juvenile baueri (3- to 4-mo-old birds) made up 1.3% ± 0.2 SD/sample (range 0.0–10.0, n = 52; REG). However, at some sites and/or late in fall, only birds present may be juveniles (Swarth 1934, McCaffery 1998b, Piersma and Gill 1998). Known to spend at least first, second, and probably third boreal summers (i.e., breeding seasons) after fledging on nonbreeding grounds. Subadults not known to have partial northward migration (Higgins and Davies 1996, Sagar et al. 1999, M. Barter and A. Riegen pers. comm.).

Bar-tailed Godwit Figure 3. Annual cycle -- Bar-tailed Godwit.
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Figure 3. Annual cycle -- Bar-tailed Godwit.

Annual cycle of migration, breeding, and molt of Bar-tailed Godwit (L. l. baueri). Thick lines show peak activity; thin lines, off-peak. Spring migration data from entire route, Australia to Alaska; fall migration shows Alaskan data only, including postbreeding movements to the staging grounds and departures to Australasia. Molt complex; only breeding-age birds depicted here (see text for details). Breeding data from Yukon-Kuskokwim Delta, AK.

Bar-tailed Godwit Adult female Bar-tailed Godwit, incubating; Alaska, June
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Adult female Bar-tailed Godwit, incubating; Alaska, June

Colville River Delta, Alaska, June.; photographer Gerrit Vyn

Bar-tailed Godwit Bar-tailed Godwit nest and eggs; Alaska, June
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Bar-tailed Godwit nest and eggs; Alaska, June

Colville River Delta, Alaska.; photographer Gerrit Vyn

Recommended Citation

McCaffery, B. J. and R. E. Gill (2020). Bar-tailed Godwit (Limosa lapponica), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.batgod.01