Photo: John Pelechaty
Probability of observation
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Click on plot to view table of mean abundance
Number of squares
Long-term BBS trends
Mean abundance (number of birds detected per 5 min. point count) and percentage of squares occupied by region
Bird Conservation Regions [abund. plot] [%squares plot]
Characteristics and Range Though often ignored or overlooked, the Savannah Sparrow is perhaps the most abundant songbird in Manitoba farmland, where it is a frequent sight on roadside wires or singing from tall plants. The male's song of high-pitched introductory notes and buzzy finale is easily lost on a breezy day. Savannah Sparrows are distinguished from other streaked sparrows by a combination of small size, short tail, a sharp demarcation between the streaked breast and white belly, and a variable yellow portion of the pale supercilium. Many subspecies have been described, some insular and coastal forms being especially distinctive, including possible candidates for future splitting (Rising 2010).
Savannah Sparrows breed throughout Canada, excluding the Arctic Archipelago and northeastern Nunavut. In forested regions they are restricted to scattered open wetlands and barrens. Their range also includes Alaska and a large portion of the northern conterminous U.S.A., extending southward somewhat in montane regions (Wheelwright and Rising 2008). Migratory populations overwinter mostly south of the breeding range, from southern U.S.A. through Mexico to northwestern Central America, plus some of the northern Caribbean islands. Several non-migratory subspecies occur in Mexico and coastal California.
Distribution, Abundance, and Habitat The atlas clearly shows separate centres of abundance in agricultural and far-northern regions of Manitoba (representing different subspecies), with only scattered occurrence elsewhere. Within the limitations of 10-km resolution, the breeding-evidence map accurately outlines the boundaries of farmland in southern Manitoba, superseding any association with specific BCRs. Patterns of overall detection, probability of observation, and abundance are broadly similar. However, the abundance map indicates reduced abundance along the Manitoba Escarpment, separating southwestern and south-central zones of peak abundance.
In southern Manitoba, the Savannah Sparrow occupies a wide range of agricultural settings. Though most numerous in hayfields, lightly grazed pastures, and prairie vestiges, it is one of few species to persist in vast expanses of monoculture cropland. In the far north, it is a bird of sedge meadows and wet tundra within the Taiga Shield & Hudson Plains (Jehl 2004). Sedge wetlands are probably also important within the boreal forest. Artificial clearings such as airfields in the boreal forest also provide some breeding habitat.
Trends, Conservation, and Recommendations The Savannah Sparrow is perhaps the songbird that is most resilient to intensive agriculture. Indeed, BBS-based mapping shows it reaching peak abundance in the agricultural plains of southern Manitoba, North Dakota, and northwestern Minnesota. Habitat preferences vary regionally. Certain agricultural practices may turn otherwise attractive habitat into population sinks; increasingly early and frequent hay mowing is especially harmful to breeding success (Wheelwright and Rising 2008). The long-term, survey-wide BBS population trend is slowly but significantly downward, though Manitoba numbers appear to be stable and Arctic populations are not surveyed. Jehl (2004), however, cited significant declines in the Churchill region since the 1960s, linked partly to overgrazing by geese. While global conservation concern is low, ongoing monitoring is essential, and adjustment of hay mowing dates would be beneficial.
Recommended citation: Taylor, P. 2018. Savannah Sparrow in Artuso, C., A. R. Couturier, K. D. De Smet, R. F. Koes, D. Lepage, J. McCracken, R. D. Mooi, and P. Taylor (eds.). The Atlas of the Breeding Birds of Manitoba, 2010-2014. Bird Studies Canada. Winnipeg, Manitoba http://www.birdatlas.mb.ca/accounts/speciesaccount.jsp?sp=SAVS&lang=en [27 Feb 2024]
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