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Northern Pintail - Anas acuta
(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
Northern Pintail (Anas acuta) Conservation Status Review
Review Date = 12/22/2011
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)
CommentWetland and adjacent terrestrial breeding habitats likely stable (+/- 25%) since European arrival.
ScoreE - Stable. Population, range, area occupied, and/or number or condition of occurrences unchanged or remaining within ±10% fluctuation
CommentBBS data for Montana is of moderate credibility with an insignigicant trend of +0.9% per year or 9% per decade. Prairie potholes region has high credibility within a +0.2% increase per year or 2% increase per decade.
ScoreF - Widespread, low-severity threat. Threat is of low severity but affects (or would affect) most or a significant portion of the population or area.
CommentHabitat loss, lead shot, agricultural contaminants, mowing, drought related to climate change, and collisions with fences and other stationary or moving objects are likely the greatest threats to the species in Montana.
SeverityLow - Low but nontrivial reduction of species population or reversible degradation or reduction of habitat in area affected, with recovery expected in 10-50 years.
CommentSpecies is a moderate generalist in habitat use with high fecundity which should allow them to recover within 10-50 years.
ScopeModerate - 20-60% of total population or area affected
CommentContaminants and other threats affect >20% of population
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. Nests in open country with shallow, seasonal, or intermittent wetlands.
Medium-sized dabbling duck. Length: adult males 57 to 76 cm, females 51 to 63 cm. Both sexes distinguished from other dabblers by slim profile, long narrow neck, and pointed tail. Sexually dimorphic plumage. Definitive Alternate male readily distinguished from other North American ducks by combination of chocolate brown head, white neck and underparts, and very long central rectrices. Female distinguished from other female ducks by slender proportions, pointed tail, mottled dull brown or bronze (rarely with some green) speculum, and mottled to spotted dark gray to black bill (Austin and Miller 1995).
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.
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
SUMMER (Feb 16 - Dec 14)
Direct Evidence of Breeding
Indirect Evidence of Breeding
No Evidence of Breeding
WINTER (Dec 15 - Feb 15)
Not Regularly Observed
(Observations spanning multiple months or years are excluded from time charts)
Normal migration periods in the Bozeman area are March 5 to May 5 and September 20 to November 20, with the peak occurring on October 20 (Skaar 1969).
Comments on habitat are found in Holm (1984). Typically nest in open country with shallow, seasonal, or intermittent wetlands and low vegetation (Austin and Miller 1995). Summer birds prefer large lakes in the Bozeman area (Skaar 1969). An early fall migrant, the species arrives on wintering areas beginning in August, after wing molt, often forming large roosting and feeding flocks on open, shallow wetlands and flooded agricultural fields (Austin and Miller 1995).
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.
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Grain (rice, wheat, corn, barley), moist-soil and aquatic plant seeds, pond weeds, aquatic insects, crustaceans, and snails (Austin and Miller 1995).
At Freezeout Lake the major cause of nest failure was skunk predation. Brood movement in southeast Montana tended to be from bare ponds to those with emergent vegetation, from small to larger ponds and to ponds with a lower water loss rate.
The species nests from late April through July, with hatchlings observed in May. At Freezeout Lake island nests were more successful (87.5%) than those in other habitats (all types averaged 34.4%). The average clutch size was 9.3; hatching dates were April 20 to July 10.
- Literature Cited AboveLegend: View Online Publication
- Austin, J. E., and M. R. Miller. 1995. Northern Pintail (Anas acuta). In The birds of North America, No. 163 (A. Poole and F. Gill, Eds.). Academy of Natural Sciences of Philadelphia and American Ornithologists’ Union. [Revised online 10 November 2014]
- Holm, I. 1984. Hatching success of upland nesting ducks in north central Montana in relation to vegetation cover. M.S. thesis, University of Montana, Missoula.
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- Additional ReferencesLegend: View Online Publication
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