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Merlin - Falco columbarius
General Description
Males are blue-gray to dark blue above and pale rufous to buff-colored below, with dark streaking or barring. Females are brown above and cream to rufous below with darker streaking. The tail is barred dark with gray to white and exhibits a dark sub-terminal band. The eye is dark brown, and feet are yellow. Juveniles of both sexes resemble females, but are sometimes darker. Merlins are from 10 to 12 inches in length, and have wingspans of 19 to 24 inches. Females are slightly larger than males. A small falcon with pointed wings, a strongly barred tail, a hooked bill, and heavy streaking below; upperparts are gray-blue in males, dark brown in females; overall, plumage is much darker in the Pacific Northwest than in central Canada and the Midwest; average length 31 cm, wingspan 64 cm.
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.Diagnostic Characteristics
Merlins are significantly smaller than Gyrfalcons, Prairie Falcons, and Peregrine Falcons. Differs from American Kestrel, Prairie Falcon, and Peregrine Falcon in lacking a strong facial pattern. Both sexes are more uniform in color, lacking russet back and tail, than the brightly colored American Kestrel. Only about half as big as a Gyrfalcon (average length 31 cm vs. 51 to 64 cm). Immature Merlins resemble immature Sharp-shinned Hawks, but have pointed wings and dark eyes, instead of the short, rounded wings and yellow eyes of the Sharp-shinned Hawk.
Species Range
Montana Range
Range Descriptions
Year-round
Western Hemisphere Range
Observations in Montana Natural Heritage Program Database
Number of Observations: 6064
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
Relative Density
Recency
SUMMER (Feb 16 - Dec 14)
Direct Evidence of Breeding
Indirect Evidence of Breeding
No Evidence of Breeding
WINTER (Dec 15 - Feb 15)
Regularly Observed
Not Regularly Observed
(Observations spanning multiple months or years are excluded from time charts)
Migration
Subspecies bendirei and richardsonii probably migrate thru MT. In Bozeman, birds appear October 1 to November 15, disappear March 1 to 15 (Skaar 1969).
Habitat
Breeding pairs in eastern Montana usually use sparse conifer stands adjacent to prairie habitats, but sometimes use shelterbelts and river bottom forests. In western Montana, they use open stands of conifers and river bottom forests. Merlins sometimes nest in urban areas. In the Bozeman area, found in the Gallatin Valley, not far from wooded 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:
mtnhp.org/requests) 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.
Literature Cited
- 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
Grassland Systems
Human Land Use
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
Food Habits
Merlins primarily eat small birds. In eastern Montana, common prey includes grassland birds such as Horned Larks, Vesper Sparrows, and Lark Buntings. In western Montana, prey includes various sparrows, finches and waxwings. Young Merlins often take larger insects such as grasshoppers and moths.
Ecology
The 1944 raptor survey of MT showed this species to be the least abundant raptor in the state (Davis 1961). Said to be formerly uncommon, now rare in the Fortine area.
Reproductive Characteristics
Male Merlins arrive at nesting areas in late March and early April, and females arrive slightly later. They use nests previously constructed by Black-billed Magpies or American Crows; Merlins, like other falcons, do not build their own nests. Used old corvid nests in MT. Clutches of three to five eggs are laid from mid April to early June, and are incubated for about 30 days. The young fly when about 40 days old, but they remain near their nests. Live to be about eight years old. Nesting dates probably similar to those of Alberta and Saskatchewan, where egg records are from May 7 to June 6 (Johnsgard 1986).
Stewardship Responsibility
References
- Literature Cited AboveLegend:
View Online Publication- Davis, C.V. 1961. A distributional study of the birds of Montana. Ph.D. Dissertation. Corvallis, OR: Oregon State University. 462 p.
Johnsgard, P.A. 1986. Birds of the Rocky Mountains: with particular reference to national parks in the northern Rocky Mountain region. Colorado Associated University Press, Boulder, CO.- Marks, J.S., P. Hendricks, and D. Casey. 2016. Birds of Montana. Arrington, VA. Buteo Books. 659 pages.
- 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
Do you know of a citation we're missing?- [PRESI] Powder River Eagle Studies Incorporated. 1998b. Spring Creek Mine 1997 wildlife monitoring studies. Powder River Eagle Studies Incorporated. Gillete, WY.
- Allen, G. T. 1979. An assessment of potential conflicts between nesting raptors and human activities in the Long Pines area of southeastern Montana with special emphasis on uranium development. M.S. thesis, Washington State University, Pullman. 109 pp.
- American Ornithologists’ Union [AOU]. 1998. Check-list of North American birds, 7th edition. American Ornithologists’ Union, Washington, D.C. 829 p.
- Becker and Sieg. 1985. Raptor Res. 19:52-55.
- Becker, D. M. 1985. Food habits of Richardson’s Merlins in southeastern Montana. Wilson Bulletin 97:226-230.
- Becker, D.M. 1977. A survey of breeding raptors on and adjacent to Custer National Forest lands in Carter County, Montana. Unpublished report including 1978 progress report. 107 p.
- Becker, D.M. 1984. Reproductive ecology and habitat utilization of Richardson's merlins in southeastern Montana. M.Sc. Thesis. Missoula, MT: University of Montana. 62 p.
- Becker, D.M., and C.H. Sieg. 1987. Eggshell quality and organochlorine residues in eggs of Merlins, Falco columbarius, in southeastern Montana. Canadian Field-Naturalist 101(3):369-372.
- Becker, D.M., and C.H. Sieg. 1987. Home range and habitat utilization of breeding male Merlins, Falco columbarius, in southeastern Montana. The Canadian Field-Naturalist 101(3):398-403.
- Becker, Dale M., 1980, A Survey of raptors on national forest land in Carter County, Montana. Final Progress Report: 1977-1979.
- Bramblett, R.G., and A.V. Zale. 2002. Montana Prairie Riparian Native Species Report. Montana Cooperative Fishery Research Unit, Montana State University - Bozeman.
- Cameron, E. S. 1907. The birds of Custer and Dawson counties, Montana. Auk 24(3): 241-270.
- Clark, T.W., H.A. Harvey, R.D. Dorn, D.L. Genter, and C. Groves (eds). 1989. Rare, sensitive, and threatened species of the greater Yellowstone ecosystem. Northern Rockies Conservation Cooperative, Montana Natural Heritage Program, The Nature Conservancy, and Mountain West Environmental Services. 153 p.
- Decker Coal Co., 1981, Wildlife survey. July 7, 1981. In North Decker 5-Year Permit Application. Vol. III. Rule 26.4.304(12-14).
- Dickson, D.C. 1991. Systematic wildlife observations on the Blackfoot-Clearwater Wildlife Management Area. Montana Department of Fish, Wildlife and Parks. Missoula, MT. 14 pp. plus appendices and photographs.
- Dobkin, D. S. 1992. Neotropical migrant landbirds in the Northern Rockies and Great Plains. U.S.D.A. For. Serv. N. Region Publ. R1-93-34. Missoula, Mont.
- Dood, A.R. 1980. Terry Badlands nongame survey and inventory final report. Montana Department of Fish, Wildlife, and Parks and Bureau of Land Management, Helena, MT. 70 pp.
- DuBois, K. and D. Becker. 1987. Identification of Montana's birds of prey. Montana Outdoors Nov/Dec. 20 p.
- DuBois, K.L. 1979. An inventory of the avifauna in the Long Pines of Southeastern Montana. M.Sc. Thesis. Bozeman, MT: Montana State University. 113 p.
- Econ, Inc. (Ecological Consulting Service), Helena, MT., 1977, 1977 wildlife and wildlife habitat monitoring study, Peabody Coal Company Big Sky Mine. Proj. 161-85-A. November 30, 1977.
- ECON, Inc. (Ecological Consulting Service), Helena, MT., 1977, Colstrip 10 x 20 Area wildlife and wildlife habitat annual monitoring report, 1977. Proj. 164-85-A. December 31, 1977.
- ECON, Inc. (Ecological Consulting Service), Helena, MT., 1979, Annual wildllife report of the Colstrip Area for 1978. Proj. 195-85-A. April 6, 1979.
- Ehrlich, P., D. Dobkin, and D. Wheye. 1988. The birder’s handbook: a field guide to the natural history of North American birds. Simon and Schuster Inc. New York. 785 pp.
- Ellis, D.H. 1976. First breeding records of merlins in Montana. Condor 78:112-114.
- Farmer, Patrick J., and Thomas W. Butts, Western Technology & Eng., Inc., Helena, MT., 1994, McDonald Project Terrestrial Wildlife Study, November 1989 - November 1993. April 1994. In McDonald Gold Project: Wildlife & Fisheries. [#18]. Seven-up Pete Joint Venture, Lincoln, MT. Unpub. No date.
- Fjell, Alan K., and Brian R. Mahan, compilers., 1984, Peabody Coal Company Big Sky Mine, Rosebud County, MT. Wildlife monitoring report: 1983 field season. February 1984.
- Fjell, Alan K., and Brian R. Mahan., 1983, Peabody Coal Company Big Sky Mine, Rosebud County, MT. Wildlife monitoring report: 1982 field season. May 1983.
- Fjell, Alan K., and Brian R. Mahan., 1987, Big Sky Mine, Rosebud County, MT. Wildlife monitoring report: 1986 field season. April 1987.
- Gniadek, S. 1983. Southwest Glendive Wildlife Baseline Inventory. Miles City, Mont: Bureau of Land Management, Miles City District Office. 56 pp with appendices.
- Gorman, J. D., 1984, Interagency Rocky Mountain Front Wildlife Monitoring/Evaluation Program.
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- Hendricks, P., and K.H. Dueholm. 1995. Cliff-nesting raptor survey of the Sioux District, Custer National Forest: 1994. Unpubl. report to U.S.D.A. For. Serv., Custer N.F., Billings. 20 pp.
- Hoffmann, R.S. 1960. Summer birds of the Little Belt Mountains, Montana. Missoula, MT: Occasional Papers of Montana State University No. 1. 18 p.
- Jellison, W.L. 1939. Sylvatic plague: studies of predatory and scavenger birds in relation to its epidemiology. Public Health Report 54: 792-798.
- Johnsgard, P.A. 1990. Hawks, eagles, and falcons of North America. Smithsonian Institution Press, Washington, D.C. 403 pp.
- Johnsgard, P.A. 1992. Birds of the Rocky Mountains with particular reference to national parks in the northern Rocky Mountain region. Lincoln: University of Nebraska Press. xi + 504 pp.
- Joslin, Gayle, and Heidi B. Youmans. 1999. Effects of recreation on Rocky Mountain wildlife: a review for Montana. [Montana]: Montana Chapter of the Wildlife Society.
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