Justification of Red List Category
This species qualifies as Vulnerable owing to a rapid ongoing population decline. The rate of decline in the USA is now not so severe as formerly, but declines may be worsening in Canada.
Rosenberg et al. (2016) estimate the U.S./Canadian population at 1,200,000 individuals, and as the species only breeds in these two countries this figure is assumed to encompass the global population. This is roughly equivalent to 800,000 mature individuals, placed here in the range of 500,000-999,999 mature individuals.
This species has undergone a large and statistically significant decrease. Partners in Flight give this species a 'half-life' of 27 years (Rosenberg et al. 2016), which equates to a decline of 20.6% over a decade. Data from North American Breeding Bird Survey over the last 47 years gives a 81.4% decline over 47 years, equating to a 30.0% decline per decade (Sauer et al. 2014). More recent trend data from 2003-2013 using Breeding Bird Survey data suggest an annual decline of 5.35% (8.81%, 2.33%), which would give a decline of 42.9% over a decade. Therefore, the decline is placed in the range of 30-49%.
Anthus spragueii breeds relatively commonly in grasslands of south-east Alberta, southern Saskatchewan, south-west Manitoba and occasionally southern British Columbia, Canada, and north and central Montana, North Dakota, and locally South Dakota, casually to north-west Minnesota, USA (Prescott 1997, Prescott and Davis 1998, Robbins and Dale 1999). It winters throughout southern USA and northern Mexico to Guerrero and Veracruz (Prescott and Davis 1998). The population has declined annually by 3.9% since 1966 (Prescott 1997, Prescott and Davis 1998, D. R. C. Prescott in litt. 1999), but the most significant declines probably occurred in the late 19th and early 20th centuries (Robbins and Dale 1999). In the USA, the decline was greatest (7.8% per year) during the 1960s and 1970s, but in Canada, the annual decline rate has slowed to 3.6% since 1980 (Sauer et al. 2007).
It inhabits well-drained native grasslands, usually in patches of at least 145 ha (Davis 2004) with density increasing with pasture size (Davis 2004), especially with sparse to intermediate grass densities, moderate litter depths, few visual obstructions and little woody vegetation (Dechant et al. 1999, Robbins and Dale 1999). It also breeds in planted grasslands in some parts of its range, predominantly those with similar vegetation characteristics to native grasslands. In particular, planted fields with a low amount of alfalfa and suitable vegetation height (20–30 cm) are likely suitable breeding sites (Fisher and Davis 2011a). On migration, it also occurs in stubble and fallow fields, arriving late April to mid-May on the breeding grounds, and late September to early November on the wintering grounds (Robbins and Dale 1999).
Conversion of prairie to seeded pasture, hayfields and cropland, and inappropriate grazing are responsible for habitat loss, degradation of remaining grassland, increased juvenile mortality and rapid declines in population (Robbins and Dale 1999, Fisher and Davis 2011b). Since 1900, c.75% of native Canadian prairies and c.80% of aspen parklands have been converted (Prescott 1997). The negative effects of such conversion can also spread into the surrounding grassland (Davis et al. 2014), with birds potentially responding to edge to area ratio (Davis 2004); distance to crops/hay (Koper and Schmiegelow 2006); or the amount of grassland in the surrounding landscape (Davis et al. 2013); as much as to area per se. Additionally, linear anthropogenic changes are associated with lowered densities (roads [Sutter et al. 2000], gas wells, pipelines, and trails [Linnen et al. 2006, Ludlow et al. 2015]). The large-scale introduction of non-native plant species and their subsequent invasion of native prairie have reduced breeding densities (Robbins and Dale 1999, Ludlow et al. 2015). Grazing and burning can have positive or negative impacts on suitable habitat depending on moisture, soil-types, plant species, intensity and frequency (Robbins and Dale 1999). Nests may be destroyed by haying prior to the fledging period. Virtual cessation of burning in the breeding zone and intensive grazing in the wintering zone has led to encroachment by shrubs and trees (Robbins and Dale 1999), and the preferred short prairie grass in wintering areas such as Texas is not conserved (J. Grantham in litt. 2003). Brood-parasitism by Brown-headed Cowbirds Molothrus ater is comparatively low, but is highest in fragmented habitat (Robbins and Dale 1999).
Conservation Actions Underway
It is listed as Threatened in Canada (COSEWIC 1999). Most habitat is unprotected but there are large areas in military reserves, national parks and on remaining provincial lands (Prescott and Davis 1998, Lipsey et al. 2015, R. Fisher and S. Davis in litt. 2016). These are relatively well protected against conversion to non-native cover. Agriculture censuses have provided some information on land-use trends, and breeding distribution and post-fledging movements are relatively well studied in Canada where monitoring programs and radio-tracking are underway (S. Jones et al. in litt. 2003, Davis and Fisher 2009). This species forms part of many grassland conservation NGO programmes in Canada (R. Fisher in litt. 2016), and receives some protection as part of the Migratory Bird Convention Act in Canada, which is part of the Migratory Bird Treaty with the USA (R. Fisher in litt. 2016). They are also incorporated in the Federal Provincial South of the Divide Action Plan for Multiple Species At Risk, and there is a recovery plan in place in Canada (see Environment Canada 2012, Environment and Climate Change Canada 2016)
16 cm. Well-marked pipit. Heavily streaked mantle, streaked crown contrasting with pale facial area, whitish supercilium and pale buff ear-coverts. Underparts buffish with faint streaking on breast. Pale legs. Similar spp. American Pipit A. rubescens is less streaked (uniform grey above in spring), has dark legs, streaked flanks and closed-faced appearance. Voice Song given in arcing flight, call a loud tweep often given in pairs. A. rubescens gives high disyllabic chip-it or tsee-tseet call. Hints In breeding season, best located when singing. Forms flocks in winter.
Text account compilers
Derhé, M., Harding, M., Pople, R., Bird, J., Wege, D., Westrip, J.
Fisher, R., Davis, S., Prescott, D., Grantham, J., Jones, S.L.
BirdLife International (2019) Species factsheet: Anthus spragueii. Downloaded from http://www.birdlife.org on 17/11/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 17/11/2019.