Vesper Sparrow Minnesota Conservation Summary
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Credit Jim Williams
Vesper Sparrow
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).
Vesper Sparrow
Priority for Blueprint for Minnesota Bird Conservation:
Prairie Parkland: Moderate Level Priority
Aspen Parkland: Moderate Level Priority
Prairie Hardwood Transition: High Level Priority
Other Status Classifications:
Identified by Partners in Flight (PIF) as a Priority Species in Minnesota
PIF BCR23: Regional Concern Species: Action is Management
Population Information:
U.S. and Canada population estimate: 30,000,000 (U.S. PIF Plan)
Continental Population Objective: Increase 50%
30% of the Vesper Sparrow’s population occurs in the Prairie Pothole Joint Venture Region
BBS data suggest a range-wide decline since the 1960s
Minnesota population estimate: 1,200,000; Target Population is 1,800,000
Estimated MN population in BCR11: 880,000; target is 1,200,000
Estimated MN population in BCR12: 61,000; target is 92,000
Estimated MN population in BCR22: 49,000; target is 74,000
Estimated MN population in BCR23: 210,000; target is 320,000
Minnesota BBS Data:
Blue Level of Regional Credibility
1966-2009: decreasing trend (statistically significant) of -1.7; 1999-2009; decreasing trend of
-1.1.
Minnesota does include one of the species centers of highest abundance
5.06% of the Vesper Sparrow’s North American breeding range occurs in Minnesota; 4.0 % of the
population occurs in Minnesota.
Average # birds/route is 12.21; found on 54 of 74 routes
Minnesota Residency:
Breeds throughout Minnesota but absent in the northeast region.
Habitat Requirements: Grassland
The Vesper Sparrow breeds in dry, open habitats with short, sparse herbaceous vegetation, some bare
ground and low to moderate shrub or tall forb cover. The species occupies many grassland habitats: native
prairie, old fields, pastures, hay lands, fence lines, croplands, roadsides and woodland edges with
scattered trees and shrubs. In the Midwest the Vesper Sparrow inhabits edge habitats, such as fencerows
and edges between croplands and woodland. It breeds in croplands, pasture and remnant native
grasslands (Birds of North America/Cornell Lab or Ornithology).
From Effects of Management Practices on Grassland Birds: Vesper Sparrow:
Vesper Sparrows prefer dry, open areas with short, sparse and patchy vegetation. However, they may
be found in a variety of habitats, including shortgrass, mixed-grass, and tallgrass prairie; semi-desert
grasslands; sagebrush; pastures; hay land; planted cover (such as CRP fields), and dense nesting
cover; cropland; shrubby grasslands; old fields; orchards; woodland edge; shelterbelts; highway
rights-of-way; and jack pine barrens.
Vesper Sparrows use the transition zones between ecosystems and edge habitats
The species uses both native and tame vegetation.
Vesper Sparrow | Page 2 of 10 | Audubon Minnesota
In Iowa, the abundance of Vesper Sparrows in roadside vegetation was inversely related to height and
vertical density of vegetation.
Quality of territories and the number of pairs using cultivated areas may be affected by availability of
elevated song perches. Perches may be any structure or vegetation higher than the nesting substrate.
From Wisconsin Bird Conservation Initiative (WBCI) Species Profile:
Vesper Sparrows prefer dry, open habitats with short, sparse vegetation, some bare ground, and short
to moderate shrub or tall forb cover.
Vesper Sparrows avoid wet areas with tall dense vegetation.
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.
Fences, shrubs, or tall weeds are preferred song perches.
In southwestern Wisconsin, Vesper Sparrows were generally more abundant in lightly-continuously
grazed, ungrazed, or rotationally grazed pastures than in heavily grazed pastures.
Vesper Sparrows affinity for shorter, sparse vegetation makes them tolerant of shorter burn rotations.
From New York Department of Conservation Species Profile:
The Vesper Sparrow is found in dry, open habitats with short, sparse and patchy herbaceous
vegetation, some bare ground, and low to moderate shrub or tall forb cover.
It occupies a broad range of grassland habitat types, including meadows, old fields, pastures,
hayfields, reclaimed surface mines, weedy fence lines, croplands, weedy roadsides, large cemeteries,
airfields, and woodland edges with scattered trees and shrubs.
Fence posts, shrubs, and small trees are used as singing perches.
Vesper Sparrows require breeding sites of at least 15 acres, but prefer areas greater than 35 acres.
A pair’s territory size ranges from 1-4 acres.
From BNA Species Profile:
The Vesper Sparrow shows no preference for native prairie; it uses both native and nonnative
grassland vegetation.
In North Dakota Conservation Reserve Program lands supported only 2.7% of the Vesper Sparrow
population, but equaled 7% of the landscape.
Migration: Temperate
Area Sensitivity: Studies have documented that the occurrence of Vesper Sparrows is sensitive to the size
of the habitat available.
Climate Change Vulnerability: Low (1); climate change models predict that the Vesper Sparrow will
change in both distribution and abundance in Minnesota as the climate warms.
Threats/Issues:
From BNA Species Account:
Changes in farming practices have been implicated in declines of this species range-wide
Intensive farming that uses chemicals and large-scale tillage contribute to declines.
Farming practices are a major cause of nest loss in agricultural areas; a trend toward earlier harvest
(e.g. June) of the first hay crop, and more frequent cutting, destroys nests.
Breeding success in cultivated and no-tillage row-crop fields generally not sufficient to maintain
populations.
Vesper Sparrow | Page 3 of 10 | Audubon Minnesota Declines of the species in their eastern range are attributed to pesticides.
From WBCI Species Profile:
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.
Pesticide use in agricultural fields is also a concern.
Early hay cutting also poses a threat to the species population (however, Vesper Sparrows are early
nesters and nest lost to hay cutting may be second nest attempts).
From New York Department of Conservation Species Profile:
Reforestation of grasslands and pastures
Loss of habitat from suburban development
Conversion of grasslands and pastures to row crops
Nest destruction due to early mowing
Although not a huge issue, nest parasitism by Brown-headed Cowbirds is a potential concern.
Predation, especially by snakes, skunks, raccoons and feral cats
OVERALL MINNESOTA GOAL: Increase current populations in Minnesota by 50% and support
grassland protection and restoration objectives in Minnesota’s Prairie Landscape Plan.
BEST MANAGEMENT PRACTICES
From Effects of Management Practices on Grassland Birds: Vesper Sparrow:
Keys to management include providing areas of dry, sparse vegetation or edge habitat between forests
and fields, and providing elevated song perches.
Vesper Sparrow are not common in planted cover.
In Minnesota, Vesper Sparrows were more common in cropland than in CRP.
Although Vesper Sparrows nest in cropland, nesting success may be low.
Specific management recommendations are as follows:
1. Burn or mow roadsides every 3-5 years to maintain vegetation quality. To reduce nest losses,
mow roadsides only in early spring or late summer. Encourage farmers to retain fence lines along
roadsides, especially in areas where forbs are sparse, to serve as perches.
2. Delay spraying pesticides and mowing in CRP until after July to avoid the peak nesting period.
3. Delay mowing grassed waterways in crop fields until late August to avoid disturbing nesting
birds. Waterways may serve as refuges because other hay lands are mowed earlier in the season.
Mow every 3-4 years to maintain grass vigor. Do not burn waterways in the fall. Burning would
have to be delayed until after fall harvest, which would preclude any regrowth of the vegetation.
Encourage the growth of forbs in waterways.
4. Maintain fencerows adjacent to cropland. Removal may reduce the use of corn and soybean
fields by Vesper Sparrows. Near cropland, increase the proportion of fencerows that consist of
both herbaceous and shrubby vegetation.
5. To increase productivity of Vesper Sparrows in crop fields, leave more corn residue and reduce
the number of mechanical field operations. Low nesting success early in the breeding season was
mostly attributed to nest destruction by mechanical field operations such as seedbed preparation
with a rotary hoe or cultivation. Adopt no-tillage practices to enhance Vesper Sparrow
Vesper Sparrow | Page 4 of 10 | Audubon Minnesotaproductivity. A decrease in tillage operations would decrease the number of nests destroyed by
tillage. Retention of crop residue on fields may increase nesting success by providing more nest
concealment cover. Reduced-tillage farming provides more foraging opportunities than
conventional-tillage methods. Use no-tillage or minimum-tillage methods to retain crop residue
and waste grain on the surface of fields for birds to use. However, the use of herbicides in no-
tillage or minimum tillage practices decreases weed-seed density.
6. If a system of strip intercropping must be used, decrease the number of passes made by farm
machinery through strips or increase time between passes to 3.5 weeks to allow the completion of
nesting cycles. As an alternative to mechanical means of week control, apply herbicides
minimally by spot spraying.
7. Limit pesticide use in areas where Vesper Sparrows forage. Use only rapidly degrading
chemicals of low toxicity at the lowest rates possible. Avoid pest outbreaks by maintaining range
in good condition. Overgrazed and drought-affected areas tend to be more prone to insect
outbreaks.
8. Plant shrubs on recontoured and reseeded strip mines to make reclaimed areas more attractive to
Vesper Sparrows. To facilitate the expansion of shrubby areas, maintain areas of shrubs along
roadsides, between mine spoils, and around equipment and storage buildings during mining and
reclamation operations.
From BNA Species Account:
While breeding numbers show a strong positive correlation with blocks >20 ha, relatively small
grassland sites 25cm tall may benefit this species.
Breeding success on crop fields could be enhanced by no-tillage agricultural practices or a reduced
number of tillage operations and increased crop residue left in fields after harvest.
From WBCI Species Profile:
In prairies and other grasslands, Vesper Sparrows colonize new areas swiftly when habitat becomes
suitable.
Management activities such as mowing, grazing, and burning can create favorable nesting conditions
for the species. However, management activities should be performed outside the breeding season
whenever possible to prevent nest loss.
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:
1. Reduce the number of passes tractors make through crop fields or increase 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.
2. No-tillage practices and an increase in crop residue will also increase nesting success and
foraging opportunities.
3. Maintaining fence rows adjacent to cropland as well as increasing the proportion of fencerows
that consist of both herbaceous and shrubby vegetation will likely benefit this species.
From New York Department of Conservation Species Profile:
Promote habitat management or enhancement activities that increase the amount of dry, native
grasslands.
Vesper Sparrow | Page 5 of 10 | Audubon Minnesota Maintain grassy and open field areas in an early successional state by conducting rotational mowing,
prescribed burning, or managed grazing
Provide elevated song perches, which can be any structure or vegetation higher than the nesting
substrate, such as dead herbaceous plants, shrubs, fences, or hay bales.
Remove woody vegetation along the edges of grassland fragments to discourage predators that may
use woody vegetation as travel corridors.
Avoid disturbance of suitable habitat during the breeding season.
From PIF Physiographic Region 16 (BCR23) Plan for grassland species; included below are those that
address Vesper Sparrow needs:
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 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.
MONITORING RECOMENDATIONS
The Vesper Sparrow is adequately monitored by the Federal Breeding Bird Survey in Minnesota.
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 Vesper Sparrows.
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).
Vesper Sparrow | Page 6 of 10 | 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 Other Grasslands
Prairie
Protection Core Areas Acquisition 71,480 91,656 acres
acres
Voluntary 154,277 acres of
management or grassland and wetland
conservation
contracts
Corridor Areas Acquisition 6,850 acres 79,224 acres
(complexes & Voluntary 131,825 acres of
general corridors) management or grassland and wetland
conservation
contracts
Matrix Landscape Acquisition 18,119 532,482 acres of
acres grassland and wetland
Voluntary 1,243,927 acres of
management or grassland and wetland
conservation
contracts
Protection Total 96, 449 170,880 acres of
acres grassland; 2,062,511
acres of grassland
and wetland
Conservation Prairie Landscape Specific Habitat
Action Conservation Areas Conservation Action Native Prairie Other
Grasslands
Restoration Core Areas 97,762 acres
of grassland
Corridor Areas 84,218 acres
(complexes & of grassland
general corridors) and wetland
Matrix Landscape 250,880 acres
of grassland
and wetland
Restoration 97,762 acres
Total 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 Vesper Sparrows.
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
Vesper Sparrow | Page 7 of 10 | Audubon Minnesotaecological 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
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 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:
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.
From PIF Physiographic Region 16 (BCR23) plan; recommendations for grassland dependent species:
Additional research is needed on the fundamental assumptions of the Grassland Bird Conservation
Area model. Specific questions include: (a) Is nesting success consistently influenced by patch size?
(b) Does the amount of grassland in the surrounding landscape influence nesting success within
specific patches? (c) Does forest cover negatively impact grassland bird nest success within patches?
(d) How many trees create a negative impact and at what distance from nesting territories?
Additional research is needed on the effects of various management practices (e.g., burning, haying,
and grazing) on the nest success of grassland birds breeding within managed grasslands in the region.
More information is needed on the effects of scale on grassland bird response to habitat management
(i.e., is bird response to management similar on large and small patches and in landscapes with high
and low levels of grass in the surrounding landscape?).
Specific management recommendations should be tested with GIS modeling.
Monitor populations to determine whether population objectives are being met. Increase monitoring
and inventory efforts for those species whose trends are unknown.
From PIF Physiographic Region 40 (BCR11) plan; recommendations for grassland dependent species:
Monitor grassland bird populations to determine whether sustained long-term population increases of
3% per year or greater are being met for species currently in decline and that trends of non-declining
species increase or remain stable.
Evaluate and compare grassland bird population growth rates in different kinds of grassland habitats,
patch sizes and landscapes.
Acquire data on abundance, productivity and survivorship of birds to determine the ability of
grassland Bird Conservation Areas (BCAs) to support source populations of grassland bird species of
concern. Determine the level at which BCAs contribute to regional population increases.
Determine the minimum area requirements of grassland birds in the Northern Tallgrass Prairie, and
how densities and reproductive success of grassland bird species vary with habitat patch size.
Investigate the dynamics of avian dispersal and colonization of sites in ephemeral systems such as
Northern Tallgrass Prairie grasslands.
Determine the influence of landscape patterns on movements of nest parasites and predators of
grassland birds.
Vesper Sparrow | Page 8 of 10 | Audubon Minnesota Continue to evaluate the effects of management practices, especially burning, mowing, grazing and
haying, on grassland birds.
Continue to develop Geographic Information Systems to identify existing and potential grassland
Bird Conservation Areas.
Effectiveness Measure: Implement conservation measures that insure that Minnesota’s Vesper Sparrow
population increases at least 3% per year.
Vesper Sparrow | Page 9 of 10 | Audubon MinnesotaAmerica
Birds of North
MNBBA 2014 Vesper Sparrow
MN DNR http://www.dnr.state.mn.us/eco/mcbs/bird_map_list.html
Vesper Sparrow Distribution Maps
Vesper Sparrow | Page 10 of 10 | Audubon Minnesota
Birds of North America http://bna.birds.cornell.edu/bna/
MNBBA Vesper Sparrow 2014
MN Breeding Bird Atlas http://www.mnbba.org/You can also read
