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Montana Field Guide

Montana Field Guides

Hooded Merganser - Lophodytes cucullatus

Potential Species of Concern
Native Species

Global Rank: G5
State Rank: S4

Agency Status
PIF: 2

External Links

General Description
The Hooded Merganser is a small (length 46 cm) duck with a thin, serrated bill and a puffy crest. The adult male has a black head with a large white patch on each side, a dark back, brown flanks, and a white chest with two black bars on each side. The adult female is brownish overall, with a yellowish lower mandible. The first-winter male resembles the female. In flight, both sexes show black-and-white inner secondaries (Peterson 1980).

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
They differ from other mergansers in being smaller, having white head patches (males), and by lacking a red bill. They differ from the Bufflehead by lacking white sides.

Species Range
Montana Range Range Descriptions

All Ranges
(Click legend blocks to view individual ranges)

Western Hemisphere Range


Observations in Montana Natural Heritage Program Database
Number of Observations: 6304

(Click on the following maps and charts to see full sized version) Map Help and Descriptions
Relative Density


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)

Montana birds that do not overwinter in the state presumably migrate to the west coast (Skaar personal communication). Migration records are from late February to early April and from September to October.

Closely associated with forested wetland systems range-wide; a broad range of breeding habitats includes emergent marshes, small lakes, ponds, beaver wetlands, forested creeks and rivers, and swamps (Dugger et al. 2009). Hooded Mergansers are generally found in river areas bounded by woods and supporting good fish populations associated with clear water (Johnsgard 1992).

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:
    1. 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);
    2. Evaluating structural characteristics and distribution of each ecological system relative to the species' range and habitat requirements;
    3. Examining the observation records for each species in the state-wide point observation database associated with each ecological system;
    4. 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: 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.

Food Habits
The Hooded Merganser's diet consists primarily of aquatic insects, fish, and crustaceans (particularly crayfish) (Dugger et al. 2009).

Females exhibit strong fidelity to breeding areas (Dugger et al. 2009).

Reproductive Characteristics
The Hooded Merganser is a cavity nester using live or dead trees. Its eggs are unusual in being almost spherical with disproportionately thick shells. The eggs are white in color. The normal clutch size is not greater than 13 (Dugger et al. 2009). Hatching dates near Fortine are for early June. Breeding occurs statewide from late June to the end of July.

Beneficial management could include establishing and maintaining cavity producing trees, and maintaining forested riparian corridors and forests within 1 km of suitable brood habitat (Dugger et al. 2009).

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Citation for data on this website:
Hooded Merganser — Lophodytes cucullatus.  Montana Field Guide.  .  Retrieved on , from