Habitat
Baird’s Sparrows breed almost exclusively in undisturbed mixed grass and tallgrass prairies. While they can sometimes be found in hayfields or pastures with some native grasses, these habitats are inferior to native grasslands. Because of this species’ secretive nature away from its breeding grounds, not much is known about the habitat they require the rest of the year. They are often seen in expansive grasslands with scattered shrubs on their wintering grounds. They are rarely seen during migration but seem to gravitate toward weedy fields and hayfields.
Back to topFood
Primarily insects and seeds captured on the ground. Prey include beetles, grasshoppers, caterpillars, leafhoppers, and flies, as well as spiders.
Back to topNesting
Nest Placement
Baird’s Sparrows nest on the ground in a shallow depression or hoofprint, usually near the base of a clump of grass.
Nest Description
The female (possibly aided by the male) builds a nest of two parts, an outer layer of grass and stems and an inner layer of fine, narrow-leafed grasses. Sometimes fur is incorporated into the inner layer. The finished nest has an inner diameter of about 2.5 inches and a depth of 2 inches.
Nesting Facts
Clutch Size: | 4-5 eggs |
Number of Broods: | 1-2 broods |
Egg Length: | 0.6-0.9 in (1.6-2.2 cm) |
Egg Width: | 0.5-0.6 in (1.2-1.6 cm) |
Incubation Period: | 11-12 days |
Nestling Period: | 8-11 days |
Egg Description: | Grayish white, with brown spots and blotches. |
Condition at Hatching: | Helpless, pink and covered with some grayish down. |
Behavior
The Baird’s Sparrow is a true grassland species that spends most of its time on the ground, though males will sit up on the tallest perch in their territory during spring and summer to sing. They typically escape pursuers by running through the grasses rather than flying over them. Baird’s Sparrows are seasonally monogamous with no extra-pair copulations recorded. Pairs maintain their territories throughout the breeding season, but the territories of many different pairs are often clustered together and adjacent to one another in good habitat. The Baird’s Sparrow defends these territories against others of its species, but they often overlap with other prairie-nesting birds like Savannah Sparrows and Chestnut-collared Longspurs, with few disputes between species. Little is known about Baird’s Sparrow behavior on their wintering grounds, but repeated mist-net captures of individuals over 3 winters in Arizona suggests that they keep a winter home range.
Back to topConservation
Baird's Sparrow populations declined by an estimated 2.2% per year between 1968 and 2015, according to the North American Breeding Bird Survey. This annual rate equates to a 65% cumulative decline over that period. Partners in Flight estimates a global breeding population of 3.4 million, rates the species a 15 out of 20 on the Continental Concern Score, and places it on the Yellow Watch List for species with declining populations. The primary cause of this decline among Baird’s Sparrows is habitat loss and degradation. The two leading causes of habitat loss are conversion of native prairie to cropland, and fire suppression. In parts of their breeding range where controlled burning is used to maintain habitat, Baird’s Sparrows are more numerous and numbers peak 2–4 years after the burn. Unburned areas become gradually dominated by woody shrubs and are avoided by the species. Some prairie protection programs including the Grassland Conservation Program help Baird’s Sparrows by maintaining native prairie habitat. Other programs, such as many lands under the Conservation Reserve Program, are less effective because they use exotic rather than native grasses. Conservation needs on the wintering grounds are largely unknown, although some work in northern Mexico’s Chihuahuan grasslands is underway.
Back to topCredits
Green, M. T., Peter E. Lowther, Stephanie L. Jones, Stephen K. Davis and Brenda C. Dale. (2002). Baird's Sparrow (Ammodramus bairdii), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Partners in Flight (2017). Avian Conservation Assessment Database. 2017.
Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2017). The North American Breeding Bird Survey, Results and Analysis 1966–2015. Version 2.07.2017. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.