Justification of Red List Category
This species is undergoing moderately rapid declines, particularly in North America. Even if populations in the rest of its range were stable the species would still be, overall, undergoing a moderate decline. Therefore, the species is listed here as Near Threatened, but further information regarding trends from outside of North America could result in the species being uplisted to a higher threat category.
Partners in Flight (2019) estimate the global population size to be 37,000,000 mature individuals.
Partners in Flight (2019) currently estimate that S. magma is undergoing annual population declines of ~3.26% throughout its range, which equates to a ~24.2% decline across the stipulated ten-year period. Such trends are supported by data from the Breeding Bird Survey, that estimates annual declines of ~3.31%, a ~28.6% decline over ten years (Sauer et al. 2017), and the Christmas Bird Count, that suggests a 3.24% rate of annual decline in the USA, ~28.1% across ten years (Meehan et al. 2018). Whilst the Breeding Bird Survey and Christmas Bird Count only refer to trends in the USA/Canada and USA respectively, Partners in Flight provide estimates for S. magna's wider population and in the absence of specific trend data from elsewhere in its range, declines are tentatively place in the range 20-29% over the stipulated ten-year period. If population declines are evidenced to be higher throughout its non-North American range however, such rates of decline would need to be placed in a higher band.
Sturnella magna has a very large range from south-east Canada, though eastern and southern U.S.A., Mexico, Central America, Cuba and into northern South America from Colombia across to northern Brazil (see Fraga 2018). It is common to locally common throughout its range (see Fraga 2018).
This species occurs in open habitats such as grassland, arable agricultural land and pasture, feeding predominantly on insect prey, although it will eat seeds and rarely fruit and carrion (see Fraga 2018). In U.S.A., breeding generally takes place from late March through to August, although in Cuba breeding is from January to July (see Jaster et al. 2012, Fraga 2018).
Degradation of land as a result of intensive agriculture, as well as grazing and trampling by livestock may be contributing to declines, and early mowing can lead to the destruction of nests and/or the mortality of young and incubating adults (see Jaster et al. 2012). Meadowlarks are vulnerable to predation from mid-sized predators and snakes. Survival of fledglings is low the first week of fledgling due to immobility of young, increasing vulnerability to snake predation (Kershner et al. 2004). Additionally, pesticide use may be leading to species mortality as both breeding females and post-fledgling juveniles have been observed to use fields treated with agricultural chemicals (Kershner 2001). Individuals of this species are often very sensitive to disturbance, such that if a female is flushed from her nest, she may abandon it (Jaster et al. 2012).
Conservation Actions Underway
This species has likely benefited from grasslands created through the Conservation Reserve Program (see Jaster et al. 2012) however, such lands must be managed to ensure they do not transition into different vegetation types; unmanaged lands are therefore often only of short term value (Kershner 2001, E. Kershner in litt. 2020). It is listed as a 'Common Bird in Steep Decline' by Partners in Flight (Rosenberg et al. 2016).
Conservation Actions Proposed
Promote contiguous grassland restoration and the removal of woody vegetation (e.g. at abandoned coal mines) as this can benefit the species (see Jaster et al. 2012, Hull et al. 2019, Lautenbach et al. 2020). Encourage appropriate land-use practices to provide suitable nesting habitat. This can include appropriate mowing regimes, which may enhance habitat quality, but such actions should be delayed until Aug to avoid causing nesting failure (see Jaster et al. 2012). Patch-burn grazing may also prove effective in removing woody vegetation and providing suitable grassland habitat (Hovick and Miller 2016). Conduct research to allow for quantification of trends outside of North America. Research other potential threats, such as fire ants (Solenopsis invicta) which have affected other bird species, parasitism by Brown-headed Cowbirds (Molothrus ater), and hybridisation with Western Meadowlark (Sturnella neglecta) to see whether these could be contributing to population trends (see Jaster et al. 2012).
Text account compilers
Kershner, E., Meehan, T., Symes, A. & Westrip, J.R.S.
BirdLife International (2021) Species factsheet: Sturnella magna. Downloaded from http://www.birdlife.org on 21/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/10/2021.