Written by: D. Dobkin, S. Granholm
Reviewed by: L. Mewaldt
Edited by: R. Duke
DISTRIBUTION, ABUNDANCE, AND SEASONALITY
Breeds commonly east of Cascade-Sierra Nevada
crest and along entire California coast,
though very locally on southern coast. Occurs primarily in grassland,
wetland, and wet meadow habitats. Coastal breeders restricted
to saline emergent wetlands
and, in northern California, to moist grasslands within the fog belt.
In the interior, breeding
occurs mostly in valleys, in moist grasslands and meadows. Montane
valleys are occupied
locally, as are hay fields. Breeds locally on western slope of
Cascade Range, in upper Kern
Basin, Kern Co., and at Baldwin Lake in San Bernardino Mts. Mostly
withdraws from Great
Basin in winter; common then in most other foothill and lowland areas
throughout the state.
At Salton Sea, winters uncommonly in desert riparian habitat, primarily
in saltcedar scrub at
river mouths. East of Sierra Nevada, winters locally north through
Owens Valley. Belding's
savannah sparrow, P. s. beldingi, lives year-round in scattered southern
(Grinnell and Miller 1944, McCaskie et al. 1979, Garrett and Dunn 1981).
SPECIFIC HABITAT REQUIREMENTS
Feeding: Eats mostly grass and other
seeds, insects, snails, and spiders. Invertebrates
predominate in breeding season, seeds are more important remainder
of year. Scratches
and gleans on ground, and picks food directly from low plants (Bent
Cover: Cover provided mostly by herbage
in grasslands, wet meadows, salicornia
wetlands, and by associated scattered shrubs and rocks. Requires
dense ground cover in
breeding season. In winter, seeks similar cover in a variety
of moist and dry grasslands,
croplands, and in low vegetation along beaches and shorelines.
Reproduction: Nests in a hollow on ground;
usually concealed by overhanging vegetation.
Builds cup nest of grasses, sedges, salicornia, with an inner lining
of fine grasses, rootlets,
and hairs (Harrison 1978).
Water: Observed to bathe and drink (Norris
1960, Bartholomew and Cade 1963), but can
survive on a diet of seeds without drinking water (Bartholomew 1972).
Pattern: Breeds mostly in dense, moist
grasslands, wet meadows, and salicornia
wetlands, with or without scattered shrubs or clumps of tall herbs.
At least in interior, ground
cover mostly less than 10 cm (4 in) high. In winter, occupies
moist and dry grasslands, but
prefers dense, short ground cover; also occurs in low vegetation in
croplands and along
beaches and shorelines.
SPECIES LIFE HISTORY
Activity Patterns: Yearlong, diurnal activity.
Seasonal Movements/Migration: Wintering
populations arrive from August to October,
depending upon the subspecies, and depart in April or May. Montane
mostly move downslope to winter.
Home Range: In Georgia, Norris (1960)
estimated a short-term winter home range at 3.2
ha (8ac). Winter density averaged 10-12 individuals per ha (4-5
per ac) and varied up to 74
per ha (30 per ac).
Territory: In Michigan pasture and fallow
farmland, Potter (1972) recorded 62 territories
averaging 0.11 ha (0.26 ac) and varying from 0.01 to 0.29 ha (0.03
to 0.71 ac); 27 territories
without nests averaged 0.08 ha (0.21 ac), and 35 territories with nests
averaged 0.12 ha (0.30
ac). In Wisconsin, Wiens (1969) reported 91 territories averaging
0.69 ha (1.7 ac) and
varying from 0.16 to 1.74 ha (0.4 to 4.3 ac). On beach dunes
in Nova Scotia, Welsh (1975)
reported 13 territories averaging 0.17 ha (0.43 ac) and varying from
0.09 to 0.33 ha (0.23 to
Reproduction: Breeds from April into
July, with a peak in May and June. Lays 2-6 eggs,
usually 4 or 5 per clutch; often double-brooded. Incubation 10-13
days; altricial young fledge
in 7-14 days. Incubation and brooding mostly by female (Bent
1968, Harrison 1978, Ehrlich et
Niche: Subject to predation by hawks,
snakes, and small mammals. May be semicolonial,
polygynous, roost in small groups on ground, or form small flocks in
winter, especially in
saline emergent wetland (Ehrlich et al. 1988).
Comments: Belding's savannah sparrow,
P. s. beldingi, frequents pickleweed in a few
scattered saline emergent wetlands from Santa Barbara Co. south.
Only a few thousand
individuals remain, but numbers may stabilize if these restricted and
remnants are protected (California Department of Fish and Game 1989).
P. s. rostratus, the
large-billed savannah sparrow, a winter visitant to saline emergent
wetland at Salton Sea and
southern coast, is a California Species of Special Concern (Grinnell
and Miller 1944).
Bartholomew, G. A. 1972. The water economy of seed-eating
birds that survive without
drinking. Proc. Int. Ornithol. Congr.
Bartholomew, G. A., and T. J. Cade. 1963. The water economy
of land birds. Auk 80:504-
Bent, A. C. (O. L. Austin, Jr., ed.). 1968. Life histories
of North American cardinals,
grosbeaks, buntings, towhees, finches, sparrows,
and allies. 3 Parts. U.S. Natl. Mus.
Bull. 237. 1889pp.
California Department of Fish and Game. 1989. 1988 annual
report on the status of
California's state listed threatened and endangered
plants and animals. Sacramento.
Ehrlich, P. R., D. S. Dobkin, and D. Wheye. 1988. The birder's
handbook. Simon and
Schuster, New York. 785pp.
Garrett, K., and J. Dunn. 1981. Birds of southern
California. Los Angeles Audubon Soc.
Grinnell, J., and A. H. Miller. 1944. The distribution
of the birds of California. Pac. Coast
Avifauna No. 27. 608pp.
Harrison, C. 1978. A field guide to the nests, eggs and
nestlings of North American birds.
W. Collins Sons and Co., Cleveland, OH.
McCaskie, G., P. De Benedictis, R. Erickson, and J. Morlan. 1979.
Birds of northern
California, an annotated field list.
2nd ed. Golden Gate Audubon Soc., Berkeley. 84pp.
Norris, R. A. 1960. Density, racial composition, sociality,
and selective predation in
nonbreeding population of savannah sparrows.
Potter, P. E. 1972. Territorial behavior in savannah sparrows
in southeastern Michigan.
Wilson Bull. 84:48-59.
Welsh, D. A. 1975. Savannah sparrow breeding and territoriality
on a Nova Scotia dune
beach. Auk 92:235-251.
Wiens, J. A. 1969. An approach to the study of ecological
relationships among grassland
birds. Ornithol. Monogr. No. 8.
Compiled from information from California Department of Fish and Game - California Interagency Wildlife Task Group