American Kestrel - Falco sparverius
(see State Rank Reason below)
State Rank Reason (see State Rank above)
Species is relatively common within suitable habitat and widely distributed across portions of the state
- Details on Status Ranking and Review
ScoreU - Unknown
ScoreG - 200,000-2,500,000 km squared (about 80,000-1,000,000 square miles)
Comment380, 531 square kilometers based on Natural Heritage Program range maps that appear on the Montana Field Guide
Area of Occupancy
ScoreU - Unknown
ScoreE - Relatively Stable (±25% change)
CommentNatural and anthropogenically altered covertypes across Montana are widely used by the species so there have likely been no substantial declines or increases since European arrival.
ScoreE - Stable. Population, range, area occupied, and/or number or condition of occurrences unchanged or remaining within ±10% fluctuation
CommentBreeding Bird Survey data for Montana is of highest credibility and shows a significant trend of -0.5% decline per year or -5% decrease per decade. Most trends in surrounding states and provinces are slightly negative, but some show slight increases. Raptor survey route data through 2011 also support a decline in Montana over the last 40 years, but trends in raptor survey route data over the last 10 years have been stable. So, overall short term trend for the region is probably best regarded as stable to slightly declining.
ScoreE - Localized substantial threat. Threat is moderate to severe for a small but significant proportion of the population or area.
CommentLoss of cavities for nesting is probably the greatest threat to this generalist predator.
SeverityModerate - Major reduction of species population or long-term degradation or reduction of habitat in Montana, requiring 50-100 years for recovery.
CommentRequires cavities for nesting and regeneration of trees that provide cavities can take lengthy periods of time.
ScopeLow - 5-20% of total population or area affected
CommentLikely less than 20% of cavity trees will be threatened over the next 20 years.
ImmediacyModerate - Threat is likely to be operational within 2-5 years.
ScoreC - Not Intrinsically Vulnerable. Species matures quickly, reproduces frequently, and/or has high fecundity such that populations recover quickly (< 5 years or 2 generations) from decreases in abundance; or species has high dispersal capability such that extirpated populations soon become reestablished through natural recolonization (unaided by humans).
CommentNot Intrinsically Vulnerable. Species matures quickly, reproduces frequently, and/or has a high fecundity such that populations recover quickly (< 5 years or 2 generations) from decreases in abundance. Species has good dispersal capabilities such that extirpated populations generally become reestablished through natural recolonization.
ScoreC - Moderate. Generalist. Broad-scale or diverse (general) habitat(s) or other abiotic and/or biotic factors are used or required by the species but some key requirements are scarce in the generalized range of the species within the area of interest.
CommentModerate Generalist. Use a variety of natural and human altered landscapes, but are dependent on cavities for nesting.
Raw Conservation Status Score
3.5 + 0.0 (geographic distribution) + 0.0 (environmental specificity) + 0.0 (short-term trend) + 0.0 (threats)
Adult males are slate-blue on their wings and the crown of their heads. The back is rufous with distinct dark brown horizontal barring. The tail is uniformly rufous with a black band on the end. The breast is buff to cream with light vertical streaking. The female is uniformly rufous on the back and wings with dark brown horizontal banding. The tail is similarly marked. The breast is buff with heavy rufous streaking. Both sexes have a dark vertical stripe below, in front of, and behind the eye, with an additional dark stripe farther back on the head. Juvenile males differ from adults in having a more heavily marked breast and brown-tipped feathers. Juvenile females are identical to adult females. American kestrels range from nine to 12 inches in length and have a wingspan of 20 to 24 inches. Pointed wings, reddish back and tail, two black stripes on each side of white sides of head; male has blue-gray wings; averages 27 cm long, 58 cm in wingspan.
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see Marks et al. 2016, Birds of Montana.
Merlins are slightly larger than American Kestrels. Female Merlins are not as rufous as female American Kestrels. Male Merlins have blue backs and wings. Sharp-shinned Hawks have more rounded wings, and have blue or brown backs and wings. Differs from Peregrine Falcon, Merlin, and Aplomado Falcon in having a reddish back and tail and double black marks on sides of head; Peregrine Falcon is much larger. Smaller than the Eurasian Kestrel (averages 34 cm long), which has only a single black mark on each side of the head.
Western Hemisphere Range
Observations in Montana Natural Heritage Program Database
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
(direct evidence "B")
(indirect evidence "b")
No evidence of Breeding
(regular observations "W")
(at least one obs. "w")
(Observations spanning multiple months or years are excluded from time charts)
Bozeman area migration: April 1 to May 5 and August 8 to October 10, peaks April 25 and September 15.
American Kestrels are found in nearly all habitats in Montana. Nests are often located in cavities in trees, banks, cliffs, and buildings. They also use man-made nest boxes. They usually hunt in open habitat. American Kestrels often perch on overhead wires or posts while looking for prey, or hover in midair. In Bozeman area, summer birds are concentrated in the valley, but some birds are found far up mountain canyons (Skaar 1969); wintering birds tend to frequent irrigated areas (Skaar 1969).
Ecological Systems Associated with this Species
- Details on Creation and Suggested Uses and Limitations
How Associations Were Made
We associated the use and habitat quality (common or occasional) of each of the 82 ecological systems mapped in Montana for
vertebrate animal species that regularly breed, overwinter, or migrate through the state by:
- Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Foresman 2012, Adams 2003, and Werner et al. 2004);
- Evaluating structural characteristics and distribution of each ecological system relative to the species' range and habitat requirements;
- Examining the observation records for each species in the state-wide point observation database associated with each ecological system;
- Calculating the percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system to get a measure of "observations versus availability of habitat".
Species that breed in Montana were only evaluated for breeding habitat use, species that only overwinter in Montana were only evaluated for overwintering habitat use, and species that only migrate through Montana were only evaluated for migratory habitat use.
In general, species were listed as associated with an ecological system if structural characteristics of used habitat documented in the literature were present in the ecological system or large numbers of point observations were associated with the ecological system.
However, species were not listed as associated with an ecological system if there was no support in the literature for use of structural characteristics in an ecological system, even if
point observations were associated with that system.
Common versus occasional association with an ecological system was assigned based on the degree to which the structural characteristics of an ecological system matched the preferred structural habitat characteristics for each species as represented in scientific literature.
The percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system was also used to guide assignment of common versus occasional association.
If you have any questions or comments on species associations with ecological systems, please contact the Montana Natural Heritage Program's Senior Zoologist.
Suggested Uses and Limitations
Species associations with ecological systems should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning.
These potential lists of species should not be used in place of documented occurrences of species (this information can be requested at: http://mtnhp.org/requests/default.asp
) or systematic surveys for species and evaluations of habitat at a local site level by trained biologists.
Users of this information should be aware that the land cover data used to generate species associations is based on imagery from the late 1990s and early 2000s and was only intended to be used at broader landscape scales.
Land cover mapping accuracy is particularly problematic when the systems occur as small patches or where the land cover types have been altered over the past decade.
Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections).
Finally, although a species may be associated with a particular ecological system within its known geographic range, portions of that ecological system may occur outside of the species' known geographic range.
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
- Dobkin, D. S. 1992. Neotropical migrant land birds in the Northern Rockies and Great Plains. USDA Forest Service, Northern Region. Publication No. R1-93-34. Missoula, MT.
- Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Hart, M.M., W.A. Williams, P.C. Thornton, K.P. McLaughlin, C.M. Tobalske, B.A. Maxell, D.P. Hendricks, C.R. Peterson, and R.L. Redmond. 1998. Montana atlas of terrestrial vertebrates. Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT. 1302 p.
- Hutto, R.L. and J.S. Young. 1999. Habitat relationships of landbirds in the Northern Region, USDA Forest Service, Rocky Mountain Research Station RMRS-GTR-32. 72 p.
- Maxell, B.A. 2000. Management of Montana's amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
- Werner, J.K., B.A. Maxell, P. Hendricks, and D. Flath. 2004. Amphibians and reptiles of Montana. Missoula, MT: Mountain Press Publishing Company. 262 p.
- Commonly Associated with these Ecological Systems
Forest and Woodland Systems
Human Land Use
Recently Disturbed or Modified
Shrubland, Steppe and Savanna Systems
Sparse and Barren Systems
Wetland and Riparian Systems
- Occasionally Associated with these Ecological Systems
Forest and Woodland Systems
Recently Disturbed or Modified
During the summer, kestrels feed heavily on large insects such as grasshoppers. Other prey includes small birds, rodents, and snakes. During winter they feed primarily on small birds and rodents.
In the 1944 raptor survey, this species made up 49.8% of raptor population in Montana (Davis 1961). Near Fortine, it is described as decreasing in numbers in recent years.
Male American Kestrels arrive at nest sites before females. A prolonged and often noisy courtship in May results in three to seven eggs, which hatch after 28 to 30 days of incubation. The young fly when they are about a month old. Parents and young often stay together for up to a month after they leave the nest. Nesting occurs in May and June, with young out of nest in July (Davis 1961). Fortine area eggs laid from early May to early June; young left nests as early as July 20.
- Literature Cited AboveLegend: View Online Publication
- Davis, C.V. 1961. A distributional study of the birds of Montana. Ph.D. dissertation. Oregon State University, Corvallis. 462 pp.
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- Skaar, P.D. 1969. Birds of the Bozeman latilong: a compilation of data concerning the birds which occur between 45 and 46 N. latitude and 111 and 112 W. longitude, with current lists for Idaho, Montana, Wyoming, impinging Montana counties and Yellowstone National Park. Bozeman, MT. 132 p.
- Additional ReferencesLegend: View Online Publication
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- Additional Sources of Information Related to "Birds"