Western Meadowlark Minnesota Conservation Summary
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Credit Jim Williams
Western Meadowlark
Minnesota Conservation Summary
Audubon Minnesota
Spring 2014
The Blueprint for Minnesota Bird Conservation is a project of Audubon Minnesota written by Lee A.
Pfannmuller (leepfann@msn.com) and funded by the Environment and Natural Resources Trust Fund.
For further information please contact Mark Martell at mmartell@audubon.org (651-739-9332).
Western Meadowlark
Priority for Minnesota’s Bird Conservation Plan:
Prairie Parkland: High Level Priority
Aspen Parklands: High Level Priority
Prairie Hardwood Transition: Highest Level Priority
Other Status Classifications:
Identified by Partners in Flight (PIF) as a Priority Species in Minnesota
PIF BCR11: Regional Concern Species: Action is Management
PIF BCR23: Regional Concern Species: Action is Immediate Action
Population Information:
U.S. and Canada population estimate: 30,000,000 (U.S. PIF Plan)
Continental Population Objective: Increase 50%
Decline of 51% documented by the BBS from 1966-2006.
Approximately 17% of the Western Meadowlark’s population occurs in the Prairie Pothole Joint
Venture Region.
Status in Wisconsin (WBCI Species Profile):
The species has experienced extreme fluctuations over the last 100 years. There are very few
records of this species in the state prior to 1900. By 1922, the Western Meadowlark was reported
as abundant and equally numerous as the Eastern Meadowlark in southern and western
Wisconsin. During the 1940s the Western Meadowlark invasion was found to have penetrated
into the extreme northern regions of the state. This range expansion was likely due in part to
changing agricultural practices (i.e. livestock and dairy farming) that favored Western
Meadowlarks. Since 1980, the BBS data show significant populations declines
Current population in the UMVGL Joint Venture Region: 1,890,000; Target is 3,781,800
Minnesota population estimate: 310,000; Target Population is 470,000
Estimated MN population in BCR11: 220,000; target is 330,000
Estimated MN population in BCR12: 22,000; target is 33,000
Estimated MN population in BCR22: 25,000; target is 38,000
Estimated MN population in BCR23: 44,000; target is 66,000
Minnesota BBS Data:
Blue Level of Regional Credibility
1966-2009: decreasing trend (statistically significant) of -7.3; 1999-2009; decreasing trend of
-7.6.
Minnesota does not include one of the species centers of highest abundance.
3.97% of the Western Meadowlark’s North American breeding range occurs in Minnesota; 1.0 % of
the Western Meadowlark population occurs in Minnesota.
Average # birds/route is 14.53; found on 54 of 74 routes
Minnesota Residency: Breeds throughout Minnesota but is absent from the far northeastern region
Habitat Requirements: Grassland
The Western Meadowlark is most common in native grasslands and lands converted from cropland to
perennial grass cover but also in weedy borders of croplands, roadsides and orchards. It prefers habitats
with good grass and litter cover and forbs; it is less abundant where vegetation is tall and dense. Western
Western Meadowlark | Page 2 of 9 | Audubon Minnesota
Meadowlarks are negatively impacted by woody vegetation in landscape matrix and by nearness to urban
edges. The species’ abundance in Minnesota is influenced by amount of grassland in the landscape (Birds
of North America/Cornell Labs or Ornithology).
From Effects of Management Practices on Grassland Birds: Western Meadowlark
Western Meadowlarks use a variety of grassland types from shrub-steppe and shortgrass prairie to
mixed-grass and tallgrass prairie.
In the Great Plains, Western Meadowlarks use a wide range of vegetation heights and densities,
although they avoid extremely sparse or tall cover. They prefer high forb and grass cover, low to
moderate litter cover, and little or no woody cover.
In general, Western Meadowlarks prefer open, treeless areas, although a few shrubs may be used as
song perches.
Suitable habitats are found in idle native and idle tame grasslands (including CRP)
Where populations of Western and Eastern meadowlarks are sympatric in the Great Plains, Western
Meadowlarks are found in dry uplands whereas Eastern Meadowlarks are found in wet lowland areas.
Estimates of male territory size are 3-13 ha.
In Minnesota, tallgrass prairie, nest depredation and Brown-headed Cowbird brood parasitism
decreased farther from woody edges, and nest depredation rates were lower on large (130-48 6 than
on small (16-32 ha) grasslands.
From BNA Species Account:
Meadowlarks are associated with intermediate height and density of grasses and forbs. Thus
management activities (or lack thereof) resulting in vegetation being tall and dense or short and sparse
will have a negative influence on populations.
Species appears unresponsive to grazing. However that may depend on rates on region: the species
may respond positively to moderate grazing in moister regions and negatively to heavier grazing in
arid sites.
From Wisconsin Bird Conservation Initiative (WBCI) Species Profile:
Western Meadowlarks inhabit pastures and small grain fields.
This species also occurs in other short, open grasslands and agriculture fields including hayfields,
short to medium height idle grasslands, dry old fields, dry-mesic prairies, and open barrens.
Western Meadowlarks typically are found in drier and more open areas than Eastern Meadowlarks,
although both can be found in the same habitat patch.
Western Meadowlarks tend to prefer habitats with less woody cover and shorter vegetation height-
density than Eastern Meadowlarks.
From Birding by Hindsight (MOU 2006):
In those Minnesota counties where both meadowlarks occur, breeding habitat present a very good
clue as to which species you’re seeing. Westerns typically prefer those larger, flatter, more upland,
and more uniform fields where agricultural croplands and plowing predominate.
Migration: Temperate
Area Sensitivity: Yes; most studies show a positive response by Western Meadowlark’s density and/or
occurrence in response to habitat size; one study demonstrated a negative response by the species density.
Climate Change Vulnerability: Medium (2)
Threats/Issues:
Western Meadowlark | Page 3 of 9 | Audubon Minnesota
From WBCI Species Account:
Native grasslands have been almost completely lost since European settlement, and agricultural land
has undergone many changes, from the era of wheat farming in the late 1800s to the dominance of
dairy farming in the mid-1900s, to the growth of row cropping in recent decades.
Existing parcels of native grasslands in the state are few, and those remaining are vulnerable to
fragmentation, row crop conversion, urban development, and forest succession.
Pastures, small grains, dry old fields, and hayfields are more common, but are still subject to the same
threats.
Surface tillage for spring weed control and early harvesting of hayfields can lead to reproductive
failure for this species.
From BNA Species Account:
Cultivation of grassland habitat directly affects breeding populations as Western Meadowlarks are
uncommon in cropland habitat.
Meadowlarks are sensitive to presence of humans in breeding territory.
OVERALL MINNESOTA GOAL: Increase current populations in Minnesota by 50% by
supporting implementation of Minnesota’s Prairie Landscape Conservation Plan in the Prairie
Region and restoring and managing grasslands in the eastern region of the state.
BEST MANAGEMENT PRACTICES
From Effects of Management Practices on Grassland Birds: Western Meadowlark
Keys to management include providing a variety of grassland types and heights, sparse woody cover,
and high forb and grass cover.
Densities of Western Meadowlarks are low immediately following burning, but increase a few years
post-burn, probably in response to recovery of vegetation and absence of woody vegetation.
Western Meadowlarks usually respond positively to light to moderate grazing and negatively to heavy
grazing although they also may exhibit no response to grazing.
Specific recommendations for Western Meadowlarks include:
1. Avoid disturbance (burning, mowing, grazing, tilling, and chemical spraying) during the breeding
season.
2. Protect large, native grassland areas and wet meadows from conversion to agricultural
production; management of native grasslands can be accomplished through burning, mowing, and
razing.
3. Continue CRP to preserve nesting habitat in the Great Plains.
4. Shape, as well as area, of management units must be taken into consideration; perimeter-area
ration strongly influenced occurrence of Western Meadowlarks in Nebraska.
5. Provide large blocks of grassland to reduce brood parasitism by Brown-headed Cowbirds, to
reduce nest depredation and to decrease amount of edge adjacent to suburban development.
6. Place any trails near forest or grassland edges to limit the fragmentation of large blocks of habitat.
7. Treat (burn, graze, or mow) portions of large areas on a rotational schedule to provide a mosaic of
successional stages.
8. In tallgrass prairie, burn RP fields every 3-5 years to reduce dense vegetation.
9. Burn or mow road rights-of-way in blocks on a 3-5 year rotational basis to maintain vegetation
quality.
10. Control encroachment of woody vegetation. In order to increase nest productivity in tallgrass
prairie fragments, remove woody vegetation to reduce edges and burn at least every 3 years.
11. Mow hayfields in late summer (after 15 July) on a 3-5 year rotational basis to maintain grass
quality and improve habitat for the following year. Mowing of CRP fields should not be done
more than every 3-5 years, should be done in late summer, and should be followed by ranking to
reduce and loosen litter.
Western Meadowlark | Page 4 of 9 | Audubon Minnesota12. On CRP fields that have been seeded to tallgrass species, use grazing to improve the breeding
habitat by reducing vegetation height, and by increasing canopy and forb coverage and
invertebrate biomass.
13. To avoid destroying nests and nestlings, undercut wheat stubble in the spring instead of using
surface tillage.
14. When pest management is required, use only rapidly degrading chemicals of low toxicity at the
lowest application rates possible.
From BNA Species Profile:
Management of grassland habitat should encourage prairie parcels that are devoid of woodland edges.
Conversion of cropland to planted grassland habitat benefits meadowlark populations.
From Landowner’s Guide to Creating Grassland Habitat for the Western Meadowlark (Oregon):
Ideal habitat for meadowlarks and other grassland birds:
Large open fields with several kinds of grasses of varying heights and densities
Contains a variety of wildflowers
Contains small patches of bare ground
Contains singing perches, such as shrubs, small trees, and scattered fence posts.
From WBCI Species Profile:
Management strategies include protecting large, native grassland areas from conversion to
agricultural production, treating (burn, graze, or mow) portions of large areas on a rotational schedule
to provide a mosaic of successional stages, controlling the encroachment of woody vegetation,
mowing hayfields in late summer (after July 15), and undercutting wheat stubble in the spring instead
of using surface tilling.
From PIF Physiographic Region 16 (BCR23) Plan; recommendations for Grassland Birds including the
Western Meadowlark:
Monitor populations of grassland species to ensure that population trends are stable or increasing.
Restore > 10 GBCAs within PIF16.
Restore grasslands to > 30% of the landscape in 3 (17 total in PIF16) ecoregional subsections (Albert
1995) of PIF16. Apply recommendations for GBCAs in these ecoregions. At a minimum, encourage
the planting of native grassland plant species and appropriate rotational mowing or grazing practices
to control woody plant succession.
From PIF Physiographic Region 40 (BCR11) Plan: recommendations for Grassland Birds:
In those areas within the Northern Tallgrass Prairie region where Bird Conservation Areas (see below
under Conservation Recommendations) are a reasonable conservation tool, we recommend a
minimum of two BCAs per approximately 40,000 hectares (100,000 acre) landscape unit. This may
allow birds to move between sites when stochastic factors and/or successional changes render a
particular site unsuitable for a particular species in the suite.
It is important that grassland habitats in the BCAs are managed on a rotational basis so that an array
of successional stages is available at any given time, requiring communication and coordination
among managers. BCA core areas should be centered on leks of Greater Prairie-Chickens whenever
possible, to provide sufficient nesting and brood cover during the breeding season.
From PIF Physiographic Region 20 (BCR12) Plan for grassland/shrubland species; included below are
those that address Meadowlark needs:
Focus management and protection priorities on grasslands that are large, diverse, support rare species,
contain minimal woody cover, and are embedded in landscapes with large amounts of open grassland
or barrens (McCoy 2000, Ribic and Sample 2001, Bakker et al. 2002). Aim to manage landscapes of
grasslands, barrens or sedge meadows at a scale of more than 4050 hectares.
Western Meadowlark | Page 5 of 9 | Audubon Minnesota Evaluate the feasibility of creating Grassland Bird Conservation Areas (GBCAs) in suitable
landscapes identified through the recommended research activity below (see Fitzgerald et al. 1998).
GBCAs are ~4000 ha in size, with a central core grassland block of 800 ha surrounded by an open
habitat matrix that includes an additional 800 to 1200 ha of scattered grassland parcels.
Identify areas appropriate for grassland-shrub management that will not conflict with other grassland
priorities. Build public-private partnerships to conserve and restore grassland-shrub habitats in
designated areas. Landscape-scale projects should be able to accommodate areas of shrub-grassland
within a grassland matrix.
Use prescribed fire with cutting and/or herbicides and grazing to prevent excessive woody
encroachment. Burns scheduled outside the breeding season for birds (Sample and Mossman 1997).
Before using prescribed burning for grassland management, determine habitat objectives:
1. If managing for grassland birds preferring no residual vegetation or woody cover requirement,
conduct short (1-2 years) burn rotations.
2. For large sites, consider only burning portions of the property in a given year to diversify both
the vegetation structure and bird community.
Identify excess or idled farm fields, fields that may not be critical for agricultural production and
fields that are usually too wet for production to form the base of a grassland conservation effort on
individual farms. Preferably these areas are adjacent to one another to create a single, large refuge
area (Undersander et al. 2000, Ochterski 2006).
Consider the rotational grazing of pastures in place of heavy, continuous grazing. Set aside one third
of a pasture area as an ungrazed and unmowed refuge from May 15-July 1 and rotationally graze the
remaining grassland area. After July 1, the refuge area can be mowed and incorporated into the
rotational grazing schedule (Temple et al. 1999).
Mow habitat parcels managed for grassland bird conservation after August 10. Where management
goals include both grassland birds and forage production, encourage mowing after July 15
Mow hayfields from the field center outward to provide cover that allows fledgling birds to escape to
the edge of the field. Flushing bars should be mounted on harvesting equipment to minimize bird
mortality during mowing operations (NRCS 1999, Ochterski 2006).
Locate idle nesting cover adjacent to hayfields to provide alternate habitat for species that renest after
mowing-induced failure of first nest attempts (Sample and Mossman 1997, NRCS 1999).
MONITORING RECOMENDATIONS
Eastern and Western Meadowlark are difficult to distinguish visually, yet their full territorial songs
are typically easy to differentiate. However, intermediate songs are sometimes reported which may
suggest hybridization (Eckert 2006). Because of these challenges, the BBS data can be a challenge,
particularly in those areas where both species occur.
CONSERVATION ACTIONS
Identify and target high priority landscapes and habitats for conservation action
Action: Identify Important Bird Areas that are a priority for this species in Minnesota
Prairie Pothole Joint Venture Region: Adopt the Minnesota Prairie Landscape Conservation Plan
(2010) habitat and restoration goals that target native prairie and grasslands in southern Minnesota
that benefit Western Meadowlarks.
Action: Use the Minnesota Prairie Landscape Conservation Plan (2010) to guide habitat protection
and restoration goals by conservation partners within Minnesota’s Prairie Pothole Landscape and by
Minnesota Audubon and conservation partners within Important Bird Areas located within the Prairie
Pothole Landscape (see habitat protection and restoration goals in following table).
Western Meadowlark | Page 6 of 9 | Audubon MinnesotaNative Prairie and Grassland Goals for the Prairie Pothole Region of Minnesota (BCR11)
Conservation Prairie Landscape Specific Habitat
Action Conservation Areas Conservation Action Native Prairie Other Grasslands
Protection Core Areas Acquisition 71,480 acres 91,656 acres
Voluntary 154,277 acres of
management or grassland and
conservation wetland
contracts
Corridor Areas Acquisition 6,850 acres 79,224 acres
(complexes & Voluntary 131,825 acres of
general corridors) management or grassland and
conservation wetland
contracts
Matrix Landscape Acquisition 18,119 acres 532,482 acres of
grassland and
wetland
Voluntary 1,243,927 acres of
management or grassland and
conservation wetland
contracts
Protection Total 96, 449 acres 170,880 acres of
grassland; 2,062,511
acres of grassland
and wetland
Restoration Core Areas 97,762 acres of
grassland
Corridor Areas 84,218 acres of
(complexes & grassland and
general corridors) wetland
Matrix Landscape 250,880 acres of
grassland and
wetland
Restoration Total 97,762 acres of
grassland; 335,098
acres of grassland
and wetland
Action: If and when it is appropriate, consider identifying Grassland Bird Conservation Areas within
the targeted areas of the Minnesota Prairie Landscape Conservation Plan to further the protection of
grasslands that will support viable populations of Western Meadowlarks.
Background: The PIF model for grassland BCA’s recommends a minimum 800 hectare (2,000 acre)
block as a core area, within a 1.6 kilometer (one-mile) wide matrix (approximately 4000 ha or 10,000
acre) surrounding the core. The matrix should provide another 1,000 hectares (2,500 acres) of
grassland habitat of some sort, with suggested minimum field sizes of 40 hectares (100 acres).
Hayfields typically cut before July 15 do not qualify as suitable habitat and may even be viewed as
ecological traps due to an almost complete loss of nests during mowing. The matrix also is intended
to function as a buffer to the core area with the intention that relatively few nest predators and
parasites will be supported by the distribution and amount of cropland/grassland within the matrix.
Trees should occupy less than 5% of the BCA, and the preference for agricultural use within the
matrix is pasture and small grains over row crops. In those areas within the Northern Tallgrass Prairie
region where BCAs are a reasonable conservation tool, we recommend a minimum of two BCAs per
Western Meadowlark | Page 7 of 9 | Audubon Minnesotaapproximately 40,000 hectares (100,000 acre) landscape unit. This may allow birds to move between
sites when stochastic factors and/or successional changes render a particular site unsuitable for a
particular species in the suite. It is also important that the grassland habitats in the BCAs are managed
on a rotational basis so that an array of successional stages is available across the landscape at any
given time, requiring communication and coordination among managers. BCA core areas should be
centered on leks of Greater Prairie-Chickens whenever possible, to provide sufficient nesting and
brood cover during the breeding season.
RESEARCH NEEDS
From WBCI Species Profile:
More research is needed on the winter distribution and habitat requirements for the northeastern
population of Western Meadowlarks.
Continued monitoring and investigation into this species’ population decline also is needed.
Additional data are needed on the extent of hybridization with the Eastern Meadowlarks at the eastern
periphery of the breeding range.
Western Meadowlark | Page 8 of 9 | Audubon MinnesotaWestern Meadowlark Distribution Maps
Birds of North America http://bna.birds.cornell.edu/bna/
Birds of North
America
MN DNR http://www.dnr.state.mn.us/eco/mcbs/bird_map_list.html
MN Breeding Bird Atlas http://www.mnbba.org/
Minnesota Breeding Bird Atlas 2014
MNBBA 2014 Western Meadowlark
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