Vesper Sparrow (Pooecetes gramineus)

Photo by Ryan BradyVesper Sparrow by Ryan BradyVesper Sparrow distribution map

Status/Protection

Population Information

Federal BBS information can be obtained at http://www.mbr-pwrc.usgs.gov/bbs/bbs.html by clicking on Trend Estimates and selecting the species in question. All estimates are for 1966-2005.

Life History

Habitat Selection

Vesper Sparrows prefer dry, open habitats with short, sparse vegetation, some bare ground, and short to moderate shrub or tall forb cover (Jones and Cornely 2002). Vesper Sparrows avoid wet areas with tall dense vegetation (Dechant et al 2001).  In Wisconsin this species occurs in row crops, fallow fields, dry sand prairie, barrens, cutover or burned over areas, and young conifer plantations. Other suitable areas include dry-mesic prairie, short to medium height idle grasslands, Grassland-shrub, dry old fields, pastures, hay fields, small grains, weedy fence lines and roadsides, orchards, woodland edge, and shelterbelts (Sample and Mossman 1997, Dechant et al 2001, Jones and Cornely 2002). Fences, shrubs, or tall weeds are preferred song perches (Jones and Cornely 2002).

In southwest Wisconsin, Vesper Sparrows were generally more abundant in lightly/continuously grazed, ungrazed, or rotationally grazed pastures than in heavily grazed pastures (Temple et al. 1999). Vesper Sparrows affinity for shorter, sparse vegetation makes them tolerant of shorter burn rotations. Several studies have shown high Vesper Sparrow abundance in areas one-year postburn (Krueger 1981, Herkert 1994, Vickery et al. 1999).

Habitat Availability

Wisconsin’s barrens and prairie habitats are becoming uncommon, fragmented, and are vulnerable to conversion, development, and forest succession. Dry old fields, fallow fields, and small grains are more common within the state, but are also vulnerable to row crop conversion and development. Although Vesper Sparrows nest in row crops, most nests are lost to predation or mechanical field operations (Rodenhouse and Best 1983).

Population Concerns

Vesper Sparrows are common throughout southern and central Wisconsin, excluding the shorelines of Lake Michigan and the Mississippi and St. Croix rivers (Robbins 1991). During the six-year period (1995-2000) of the Wisconsin Breeding Bird Atlas, observers confirmed breeding on nearly 20% of the surveyed quads (Schultz 2006). Although this species is widespread in the state, Breeding Bird Survey data suggest a range-wide decline since the 1960s (Sauer et al. 2005). There is little information on the possible cause(s). The most likely cause appears to be the loss of grassland habitats to forest, agriculture, and urbanization. Other factors may include pesticide use in agricultural fields (Jones and Cornely 2002) and earlier hay cutting. However, Vesper Sparrows are early nesters and nests lost to hay cutting may be second nest attempts (Robbins 1991).

Recommended Management

In prairies and other grasslands, Vesper Sparrows colonize new areas swiftly when habitat becomes suitable (Jones and Cornely 2002). Management activities such as mowing, grazing, and burning can create favorable nesting conditions for this species (Dechant et al. 2000). However, management activities should be performed outside the breeding season whenever possible to prevent nest loss. Conservation and management strategies for this species should be focused in the following Wisconsin ecological landscapes: Central Sand Plains, Northeast Sands, Northwest Sands, Southeast Glacial Plains, Southwest Savanna, and Western Coulee and Ridges (WDNR 2005). Within these landscapes, public lands important for the management of this species include Namekagon/Douglas County Barrens, Crex Meadows/Fish Lake Complex, and Necedah Barrens (David Sample, pers. comm.).     

Since Vesper Sparrows nest in cropland and small grains, there are a number of things farmers can do to reduce nest loss and still maintain their crops. Reducing the number of passes tractors make through crop fields or increasing the time interval between passes will increase reproductive success in row crops. Passes greater than 3.5 weeks apart will allow time for Vesper Sparrows to complete their nesting cycle before the next tractor pass (Sample and Mossman 1997). No-tillage practices and an increase in crop residue will also increase nesting success and foraging opportunities (Dechant et al. 2000). Maintaining fencerows adjacent to cropland as well as increasing the proportion of fencerows that consist of both herbaceous and shrubby vegetation will likely benefit this species (Rodenhouse and Best 1983).

Research Needs

Causes and limiting factors for the Vesper Sparrow population declines need to be identified. More research is needed on habitat requirements of this species. Studies of nesting success under alternate management regimes in grassland habitats are needed, as well as long-term effects of nesting in agricultural fields (Jones and Cornely 2002).

Information Sources

References

Contact Information

Kreitinger, K., Y. Steele and A. Paulios, editors. 2013.
The Wisconsin All-bird Conservation Plan, Version 2.0. Wisconsin Bird Conservation Initiative.
Wisconsin Department of Natural Resources. Madison, WI.

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