Long-billed Curlew - Numenius americanus
The Long-billed Curlew is the largest shorebird in North America. It is considered an endemic to the Great Plains. The Long-billed Curlew's long, decurved bill is adapted for capturing invertebrates living in mudflats on its wintering grounds (Dugger and Dugger 2002). Its familiar "curlew
" call can be heard throughout the mixedgrass prairie of Montana during the spring and summer.
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see Marks et al. 2016, Birds of Montana.
Migrants arrive in Montana late March to mid-April. Adults observed on nests with eggs in mid- to late-May. Adults with young birds observed in early June to early July. Females leave breeding grounds before males; tagged females left around June 28 and tagged males left July 28 (see Migration, below).
The large size, long decurved bill, and cinnamon color is diagnostic of this species. Sexes are similar in appearance, but females average slightly larger than males. Plumages are similar throughout the year. Body is a rich buff tinged with cinnamon or pink. Upperparts are streaked with dark brown. Juveniles are similar to adults except the bill is much shorter (Dugger and Dugger 2002).
Western Hemisphere Range
The Long-billed Curlew occurs throughout Montana except for extreme Northwest Montana and the southern Bitterroot (Montana Bird Distribution Committee 2012).
Observations in Montana Natural Heritage Program Database
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
SUMMER (Feb 16 - Dec 14)
Direct Evidence of Breeding
Indirect Evidence of Breeding
No Evidence of Breeding
WINTER (Dec 15 - Feb 15)
Not Regularly Observed
(Observations spanning multiple months or years are excluded from time charts)
Fourteen birds breeding in Phillips County were tracked with satellite transmitters between 2009 and 2011. All individuals migrated east of the Rocky Mountains via direct routes to wintering areas in the Texas Panhandle south to the Mexican Plateau or near the Gulf of Mexico; total distances averaging 2,500 to 2,700 km (Page et al. 2014). Northbound migrations took place between mid March and mid April and averaged 29 days (range = 15-41). Southbound migrations took place between early July and early September and averaged 68 days (range 4-119). Males arrived at breeding areas earlier and departed later than females. Montana birds stopped more often and for longer time periods than Oregon and Nevada birds (Page et al. 2014).
The Long-billed Curlew breeds in mixedgrass prairie habitats and moist meadows throughout Montana. It prefers to nest in open, short-statured grasslands and avoids areas with trees, dense shrubs, or tall, dense grasses (Dugger and Dugger 2002).
Ecological Systems Associated with this Species
- Details on Creation and Suggested Uses and Limitations
How Associations Were Made
We associated the use and habitat quality (common or occasional) of each of the 82 ecological systems mapped in Montana for
vertebrate animal species that regularly breed, overwinter, or migrate through the state by:
- Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Foresman 2012, Adams 2003, and Werner et al. 2004);
- Evaluating structural characteristics and distribution of each ecological system relative to the species' range and habitat requirements;
- Examining the observation records for each species in the state-wide point observation database associated with each ecological system;
- Calculating the percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system to get a measure of "observations versus availability of habitat".
Species that breed in Montana were only evaluated for breeding habitat use, species that only overwinter in Montana were only evaluated for overwintering habitat use, and species that only migrate through Montana were only evaluated for migratory habitat use.
In general, species were listed as associated with an ecological system if structural characteristics of used habitat documented in the literature were present in the ecological system or large numbers of point observations were associated with the ecological system.
However, species were not listed as associated with an ecological system if there was no support in the literature for use of structural characteristics in an ecological system, even if
point observations were associated with that system.
Common versus occasional association with an ecological system was assigned based on the degree to which the structural characteristics of an ecological system matched the preferred structural habitat characteristics for each species as represented in scientific literature.
The percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system was also used to guide assignment of common versus occasional association.
If you have any questions or comments on species associations with ecological systems, please contact the Montana Natural Heritage Program's Senior Zoologist.
Suggested Uses and Limitations
Species associations with ecological systems should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning.
These potential lists of species should not be used in place of documented occurrences of species (this information can be requested at: mtnhp.org/requests
) or systematic surveys for species and evaluations of habitat at a local site level by trained biologists.
Users of this information should be aware that the land cover data used to generate species associations is based on imagery from the late 1990s and early 2000s and was only intended to be used at broader landscape scales.
Land cover mapping accuracy is particularly problematic when the systems occur as small patches or where the land cover types have been altered over the past decade.
Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections).
Finally, although a species may be associated with a particular ecological system within its known geographic range, portions of that ecological system may occur outside of the species' known geographic range.
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
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- Maxell, B.A. 2000. Management of Montana's amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
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- Commonly Associated with these Ecological Systems
- Occasionally Associated with these Ecological Systems
Human Land Use
Recently Disturbed or Modified
Shrubland, Steppe and Savanna Systems
Wetland and Riparian Systems
During the breeding season, the Long-billed Curlew feeds in open prairie grasslands and meadows, at the edges of prairie ponds and sloughs, and occasionally in agricultural fields (Dark-Smiley and Keinath 2004). This species is an opportunistic forager, feeding on primarily invertebrates and also small vertebrates such as bird eggs and nestlings (Dugger and Dugger 2002). In winter, the Long-billed Curlew feeds at tidal areas and mudflats by probing with its long, decurved bill. Main prey taken includes crab, shrimp, and bivalves. Earthworms are also important on coastal pastures (Dugger and Dugger 2002).
The Long-billed Curlew will occasionally parasitize nests of other Long-billed Curlews. Long-billed Curlew and Willet will parasitize each other's nest (Dugger and Dugger 2002).
Long-billed Curlew pairs quickly establish territories after arrival on the breeding grounds, with nest-building beginning within a week of pair formation (Dugger and Dugger 2002). Nest is located in a shallow scrape or depression in the ground; male typically creates scrape. The female lines the scrape with small pebbles, bark, livestock and other animal droppings, grass, and other plant parts. Nests are often placed near a conspicuous object such as rocks or dung piles. Clutch size averages 4 (range 2-5 eggs) with only one brood per season. Both parents incubate eggs for 28-31 days. Chicks can walk within five hours of hatching and feed on their own within 10 hours. Both adults brood young chicks until about two weeks after hatch. Female generally abandons brood 2-3 weeks after hatch, and male tends young until fledging at 38-45 days (Dugger and Dugger 2002).
The Long-billed Curlew requires short-statured grasslands during the breeding season. Conversion of prairie to cropland, off-road vehicle use, and other disturbances all negatively impact Long-billed Curlew populations. Livestock grazing, particularly early season grazing, typically has a positive benefit on nesting Long-billed Curlews, although year-round grazing can be detrimental (Dugger and Dugger 2002).
Threats or Limiting Factors
Degradation or loss of grassland breeding habitat to agricultural and residential development is the greatest threat to the Long-billed Curlew. Additionally, other human disturbances such as off-road vehicle travel and agricultural practices such as chaining or dragging to remove sagebrush can destroy nests if done in the spring (Dark-Smiley and Keinath 2004).
- Literature Cited AboveLegend: View Online Publication
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- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
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