16
17
migration used sparsely vegetated wetlands (less than
33 percent vegetation cover), and use of such wetlands
exceeded availability during later summer and fall
(Davis 1996). Deep water (over 16 cm deep) was not
used, but use (46.2 percent) of shallowly flooded (0
to 4 cm) habitat exceeded availability (10.2 percent);
moderately flooded (4 to 16 cm) and wet mud were used
in proportion to availability (Davis 1996).
Microhabitat
Dominant plants in different parts of the
curlew’s range include common buffalo grass (Buchloe
dactyloides), blue grama grass (Bouteloua gracilis),
and prickly pear cactus (Opuntia spp.) in Colorado
(Graul 1971, King 1978); several species of bluestem
(Andropogon spp.), needle and thread (Stipa comata),
sixweek’s fescue (Festuca bromides), and sand dropseed
(Sporobolus cryptandrus) in Nebraska (Bicak 1977);
cheatgrass brome (Bromus tectorum) and medusa-head
wild rye (Taeniatherum asperum) in Idaho (Redmond
et al. 1981); cheatgrass brome, Sandberg’s bluegrass,
and medusa-head wild rye, but also shrubbier
habitats dominated by saltgrass (Distichlis spicata),
greasewood (Sarcobatus vermiculatus), or sagebrush
in southeastern Washington and the Columbia and
Northern Great Basins (Pampush 1980); blue grama
grass, spike moss (Selaginella densa), fringed
sagebrush (Artemisia frigida), golden aster (Chrysopsis
villosa), and blackroot sedge (
Carex eleocharis) in the
Northern Great Plains (Kantrud and Kologiski 1982);
pickleweed (Salicornia europaea), Bassia spp., Suaeda
spp., saltgrass, and pigweed (Chenopodium album)
around Great Salt Lake, Utah (Paton and Dalton
1994); and wire grass (Juncus balticus) and mountain
timothy (Phleum alpinum) in Wyoming (Cochrane and
Anderson 1987). Based on nest density (Oregon), long-
billed curlews favored cheatgrass-dominated grasslands
(9 nests per km
2
, range = 5–22.5) over bunchgrass (3.5
nests per km
2
, range = 0–7.5), dense forb (3.3 nests per
km
2
, range = 0–5), open low shrub (2.5 nests per km
2
,
range = 0–5), or bitterbrush (1.3 nests per km
2
, range
= 0–2.5) habitats (Pampush and Anthony 1993). These
preferences are likely related to vegetation structure
and not specific plant-species composition (Jenni et
al. 1981).
Long-billed curlews also nest in agricultural fields
in the Great Basin, including wheat stubble; fallow
fields; and short, dry, cereal-grain fields (Pampush
1980). Curlews use cultivated hay fields dominated by
timothy (Phleum pratense), redtop (Agrostis palustris),
reed canary grass (Phalaris arundinacea), alsike
clover (Trifolium hybridum), milkvetch (Astragalus
spp.), meadow foxtail (Alopecurus pratensis), and
alfalfa (Medicago sativa) in Wyoming (Cochrane
and Anderson 1987). Curlews are not reported to use
agricultural fields for nesting in Idaho, but they do
forage in agricultural fields throughout the breeding
season (Jenni et al. 1981). During brood rearing,
curlews use habitats with taller vegetative structure
(up to 25 cm) and greater vertical density (76 to 100
percent) than nest-site habitats (King 1978).
Vegetation at nest sites is “patchier” than curlew
habitat in general (Pampush and Anthony 1993, Hooper
and Pitt 1996), with mean vegetation height <10 cm
(King 1978, Allen 1980, Jenni et al. 1981, Hooper
and Pitt 1996) and mean vertical vegetation density
<50 percent (Jenni et al. 1981, Hooper and Pitt 1996).
In Colorado, mean vegetation height at nests was 11
cm ± 6.73 SD (range = 4-23, n = 7); mean vegetation
density was 72.1 percent ± 19.55 SD (range = 50-95;
King 1978). In Utah, nests were in clumps of thick
residual and growing vegetation with relatively little
bare ground present (n = 10; Paton and Dalton 1994).
In British Columbia, preferred nest sites included flat,
grassy uplands or gravelly ridges and hillsides; curlews
avoided tall, thick patches of grass or sagebrush
(Campbell et al. 1990). In Idaho, curlew abundance was
negatively correlated with vegetation height and percent
vertical coverage (Bicak et al. 1982).
Long-billed curlews generally choose relatively
dry, exposed sites for nests. However, the presence of
water has a direct bearing on the initiation of nesting,
and curlews may desert otherwise appropriate areas in
dry years (Ligon 1961). Long-billed curlews frequent
areas of moist soils where prey populations are higher.
In the Riske Creek area of British Columbia, nests were
more common on gentle, north-facing slopes (3°) at
high elevations (mean = 940 m; Hooper and Pitt 1996).
The average slope at nests in Colorado was 1.3 percent ±
0.85 SD (range = 0.6–3.0, n = 7; King 1978). In Alberta,
nests tended to occur more often along transects that
did not include wetlands (Gratto-Trevor 1999). In
Wyoming, nests were more common on hummocks or
higher, drier ground (Cochrane and Anderson 1987). In
Colorado, nests were located 50 m to over 1.6 km from
water, but 41 percent were located within 100 m (n = 63;
McCallum et al. 1977).
Nests are often located near conspicuous objects,
including livestock dung piles, rocks, and dirt mounds
(King 1978, Allen 1980, Cochrane and Anderson 1987).
In southeastern Colorado, six of seven nests were were
no more than 20 cm from dung piles (King 1978). In
southeastern Washington, 37 percent of the nests were