American White Pelican - Pelecanus erythrorhynchos
State Rank Reason (see State Rank above)
American White Pelicans breed at five sites in Montana. Due to limited distribution of breeding sites, the species is potentially at risk of declines.
- Details on Status Ranking and Review
ScoreF - 10,000-100,000 individuals
CommentIn 2009 and 2010, the Montana colonial-nesting waterbird survey documented 5,938 and 4,866 breeding pairs in Montana, respectively (Wightman and Tilly 2010). So total adult population is greater than 10,000 and/or between 10,000 and 100,000 (F).
ScoreU - Unknown
Area of Occupancy
ScoreE - 100-500 km squared (about 25,000-125,000 acres)
Comment222 square kilometers based on Species Occurrence polygons with known breeding activity in the Heritage database
ScoreE - Relatively Stable (±25% change)
CommentLake and isolated island habitats are stable or increasing since European arrival.
ScoreE - Stable. Population, range, area occupied, and/or number or condition of occurrences unchanged or remaining within ±10% fluctuation
CommentNest trend data in the Heritage database (partially summarized by Hendricks and Johnson (2002)) and compared with recent waterbird surveys (Wightman and Tilly 2010) indicates stable trends in 4 Montana colonies with regular breeding and nest monitoring data within mostly a +/-10% range.
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.
CommentAltered hydrology as a result of climate change, nest site disturbance, and disease (Avian Cholera, Botulism, and West Nile Virus) probably represent the greatest threats to the species.
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.
CommentWhen conditions are right adults seem to be able to make use of available nest sites (probably move between colonies more than has been documented).
ScopeHigh - > 60% of total population or area affected
CommentHigh interaction of breeding colonies on winter range and correlation of threats on breeding range.
ImmediacyModerate - Threat is likely to be operational within 2-5 years.
ScoreB - Moderately Vulnerable. Species exhibits moderate age of maturity, frequency of reproduction, and/or fecundity such that populations generally tend to recover from decreases in abundance over a period of several years (on the order of 5-20 years or 2-5 generations); or species has moderate dispersal capability such that extirpated populations generally become reestablished through natural recolonization (unaided by humans).
CommentModerately Vulnerable. Species exhibits moderate age of maturity, frequency of reproduction, and/or fecundity such that populations generally tend to recover from decreases in abundance within 5-20 years or 2-5 generations. Species has good dispersal capabilities such that extirpated populations generally become reestablished through natural recolonization.
ScoreA - Very Narrow. Specialist. Specific habitat(s), substrate(s), food type(s), hosts, breeding/nonbreeding microhabitats, or other abiotic and/or biotic factor(s) are used or required by the Element in the area of interest, with these habitat(s) and/or other requirements furthermore being scarce within the generalized range of the species within the area of interest, and, the population (or the number of breeding attempts) expected to decline significantly if any of these key requirements become unavailable.
CommentSpecies is dependent on very specialized nesting habitat (isolated islands which are limited in Montana).
Raw Conservation Status Score
3.5 + 0.0 (population size) - 0.5 (environmental specificity) + 0.0 (short-term trend) + 0.0 (threats)
The American White Pelican is a large, white bird (length: 127 to 165 cm; weight: most birds 5.0 to 9.0 kg; wingspan: 2.4 to 2.9 m) with black primaries and outer secondaries, an enormous bill with distensible gular pouch, and totipalmate webbed feet. It is often seen in flocks, and when in flight it flies with the head withdrawn. In the early breeding season the bill and legs are bright orange, the head has white plumes, and there is a laterally flattened horn on the upper mandible. Later the leg color fades, the head darkens, and the plumes and horn are lost (Evans and Knopf 1993).
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.
The American White Pelican is unlike other North American birds, except the Brown Pelican (Pelecanus occidentalis), which does not occur inland, and is smaller with generally darker body plumage, and often forages by plunge-diving, whereas the American White Pelican does not (Evans and Knopf 1993). The Snow Goose (Chen caerulescens) and Whooping Crane (Grus americana) display contrasting black primaries and a white body when in flight, similar to the American White Pelican, but are quite different otherwise in appearance and behavior. Snow Geese are much smaller and fly with their neck extended. Whooping Cranes are often confused with American White Pelicans but are easily distinguished because they fly with their legs and neck extended.
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)
American White Pelicans in Montana are long-distance migrants. Winter recoveries have been made in southern California, and south along the Pacific coast of Mexico and Central America to southern Honduras; along the Gulf coast in the United States there are recoveries from southern Florida to Texas, and south in Mexico to Vera Cruz. There are also scattered winter records from several localities in interior North America (Hendricks and Johnson 2002, E. Madden and M. Restani, personal communication).
All colonies have some members that migrate both east and west of the Continental Divide, although the majority of the two western colonies in Montana (Arod Lakes and Canyon Ferry) migrate west across the Continental Divide to southern California and south into Mexico and Central America, whereas the majority of the two eastern colonies in Montana (Bowdoin and Medicine Lake) migrate south and east to the Gulf of Mexico coast and into eastern Mexico. Recoveries or resightings indicate many birds return in spring to their natal colonies to attempt breeding, but there are also a few cases of birds banded at their natal colony returning later to a different Montana colony (Hendricks and Johnson 2002, E. Madden and M. Restani, personal communication).
Habitat use in Montana appears similar to other areas within the breeding range. American White Pelicans occur on a variety of aquatic and wetland habitats, including rivers, lakes, reservoirs (both large and small), estuaries, bays, marshes, and sometimes in inshore marine habitats. These habitats are used variously for nesting, loafing, and feeding. They rest on islands and peninsulas, as well as exposed rocks in rivers. Nesting colonies usually are situated on islands or peninsulas in brackish or freshwater lakes, where they are isolated from mammalian predators. Nests are built on the ground in slight depressions or on mounds of earth and debris, usually on low, flat, or gently sloping terrain. They may use dredge spoil or natural islands. Usually nests are built in an open area, but often near vegetation, driftwood, or large rocks (Spendelow and Patton 1988). There is increasing concentration and feeding at catfish aquaculture operations during the non-breeding season (King and Grewe 2001).
Montana breeding colonies are located in the eastern prairie regions on islands or peninsulas of low topographic relief at lakes and reservoirs. Cover at some colonies is minimal, with nests mostly or completely exposed, but nests are often under extensive stands of chokecherry (Prunus virginiana) in the main sub-colony at Medicine Lake (Hendricks and Johnson 2002). Feeding occurs near the colony as well as at remote locations (> 100 km) away from the colony in reservoirs, lakes, and along rivers.
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.
Diet at Montana colonies has not been quantified or studied, but observations of prey remains at the Medicine Lake colony include Common Carp (Cyprinus carpio), Fathead Minnow (Pimephales promelas), suckers (Catostomus spp.), Northern Pike (Esox lucius), Goldeye (Hiodon alosoides), sturgeon (Scaphirhynchus spp.), and adult and larval Tiger Salamanders (Ambystoma tigrinum) (Hendricks and Johnson 2002).
Food observed being consumed at the Canyon Ferry and Arod/"Eyraud" colonies was primarily non-game fish including suckers, carp, and bullheads.
Distances traveled by adults from nesting colonies to foraging areas can be as much as 100-300 km (Low et al. 1950, Marshall and Giles 1953, Lingle and Sloan 1980, Johnsgard 1993). When foraging in mixed-species flocks, especially with Double-crested Cormorants, stealing prey from neighbors (kleptoparasitism) is common. Breeding adults are estimated to eat about 20 to 40% of their body mass in prey (1.8 kg) per day (Evans and Knopf 1993).
Breeding colony islands in Montana are shared with Double-crested Cormorants and California Gulls. In July, adults appear to go out to feed about dawn, and return in mid-late morning to feed the nestlings.
Generally, this species is very gregarious, often found in flocks or large concentrations throughout the year. Colonies may be quite large, averaging about 1000+ pairs across the global range. In recent years, the size of Montana colonies has been 500-4000 pairs and is increasing (Hendricks and Johnson 2002). Nesting islands often are shared by other colonial-nesting species, including Double-crested Cormorant, Great Blue Heron, Black-crowned Night-Heron, Common Tern, California Gull, and Ring-billed Gull at Montana colonies (Hendricks and Johnson 2002). Severe weather, especially hailstorms, can sometimes cause significant mortality among adults and young. Predators at breeding colonies include Common Raven, several large gull species, Coyote, and Red Fox on eggs and young; Great Horned Owl and Bald Eagle take young pelicans (Evans and Knopf 1993).
American White Pelicans arrive at Montana colonies in April, egg-laying and incubation occur during late April through May, young are born in late May and June, and juveniles remain in the colonies until mid-August (Hendricks and Johnson 2002). At Medicine Lake, the mean number of young produced per nesting pair since 1990 is 0.51. The oldest bird recovered from a Montana colony was 20 years of age.
Egg-laying most often occurs in April and May throughout the global range, May to July in Texas, and late April to June (mainly before June) in Utah. In Canada, nesting begins in May or June; hatching in the first nests sometimes precedes initiation of the last clutches. The earliest migrants appear at colonies up to 3 weeks before pairing. The period from courtship flights to the onset of egg-laying is about a week. In Manitoba, flocks first flew over colony sites 34-38 days before hatching. Clutch size is commonly 2, but rarely more than one young is fledged per nest. Incubation averages 31 to 32 days. Both adults incubate eggs and tend the young. Young leave the nest in about 17 to 28 days while still flightless, and form groups with other young within the colony. In most colonies, juvenile departure begins in late August, when young are about 10 to 11 weeks of age and 1 week after their first flights (Evans and Knopf 1993).
Mortality of eggs and chicks generally is high, and they generally do not renest following loss of the first clutch. Pelicans reach sexual maturity usually at 3 years of age, and may live 25 years or more (Evans and Knopf 1993).
The four Montana breeding colonies fall into two groupings, based on flyway affiliation. Medicine Lake and Bowdoin are mostly connected to the Central Flyway, with the majority of birds flying south and east to the Gulf of Mexico coast and southern Midwest. Birds at Arod/"Eyraud" Lakes and Canyon Ferry largely cross the Continental Divide and fly west and south to southern Idaho, California, and western Mexico. While each of the Montana breeding colonies is protected to some degree from predators, human disturbance, and water level fluctuations (each occurs on federal refuges or state management areas), they are vulnerable in winter to shooting and disease. These two factors accounted for 21 to 47% of band recoveries for the Arod/"Eyraud" Lakes, Bowdoin, and Canyon Ferry colonies (Hendricks and Johnson 2002). Botulism also leads to the death of several hundred adults and young at the Medicine Lake colony during outbreak years (Hendricks and Johnson 2002), and severe weather during the breeding season can contribute to significant mortality at colonies, especially if breeding adults are killed. Conservation of American White Pelicans requires coordinated management at widely separated breeding and wintering sites, as colonies are linked regionally to other breeding colonies through dispersal. Probably the most significant factor in protecting breeding colonies in Montana is maintaining water at appropriate levels to prevent mammalian predator access or flooding of nesting areas. Montana pelicans experienced significant declines in the 1960's and 1970's due to water level fluctuations at their breeding colonies (Sloan 1982). Non-breeding season threats from disease and shooting could also be significant at times, although their impact on colony dynamics is not clear (Hendricks and Johnson 2002). A concurrent color-marking program at each of the Montana colonies, with routine pre- and post-breeding surveys for marked birds, could clarify the isolation of the two colony groupings, the degree of dispersal among the individual colonies within each grouping, and better document colony dispersal during the non-breeding season. The results of this and further studies would help in developing regional management plans that 1) identify current and impending threats to breeding and wintering populations linked through dispersal, 2) provide for coordinated responses to those threats, and 3) support the maintenance of viable populations throughout their global range.
- Literature Cited AboveLegend: View Online Publication
- Evans, R. M., and F. L. Knopf. 1993. American White Pelican (Pelecanus erythrorhynchos). In The birds of North America, No. 57 (A. Poole and F. Gill, Eds.). Academy of Natural Sciences of Philadelphia and American Ornithologists’ Union. [Revised online 1 November 2004]
- Hendricks, P. and R. F. Johnson. 2002. Movements and mortality of American white pelicans fledged in three Montana colonies. Report to the U.S. Fish and Wildlife Service. Montana Natural Heritage Program, Helena, MT. 16 pp.
- Johnsgard, P. A. 1993. Cormorants, darters, and pelicans of the world. Smithsonian Institute Press, Washington, D.C. xiv + 445 pp.
- King, D. T. and A. H. Grewe, Jr. 2001. Movements and mortality of American white pelicans banded at Marsh Lake, Minnesota. North American Bird Bander 26:57-60.
- Lingle, G. R. and N. F. Sloan. 1980. Food habits of white pelicans during 1976 and 1977 at Chase Lake National Wildlife Refuge, North Dakota. Wilson Bulletin 92:123-125.
- Low, J. B., L. Kay, and D. I. Rasmussen. 1950. Recent observations on the white pelican on Gunnison Island, Great Salt Lake, Utah. Auk 67:345-356.
- Marks, J.S., P. Hendricks, and D. Casey. 2016. Birds of Montana. Arrington, VA. Buteo Books. 659 pages.
- Marshall, D. B. and L. W. Giles. 1953. Recent observations of birds of Anaho Island, Pyramid Lake, Nevada. Condor 55:105-116.
- Sloan, N. F. 1982. Status of breeding colonies of white pelican in the United States through 1979. American Birds 36:250-254.
- Spendelow, J. A. and S. R. Patton. 1988. National atlas of coastal waterbird colonies in the contiguous United States: 1976-1982. U.S. Fish and Wildlife Service, Biological Report 88(5). x + 326 pp.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- American Ornithologists Union. 1983. Checklist of North American birds, 6th Edition. 877 PP.
- American Ornithologists’ Union [AOU]. 1998. Check-list of North American birds, 7th edition. American Ornithologists’ Union, Washington, D.C. 829 p.
- Bramblett, R.G., and A.V. Zale. 2002. Montana Prairie Riparian Native Species Report. Montana Cooperative Fishery Research Unit, Montana State University - Bozeman.
- Carlsen, T. and R. Northrup. 1992. Canyon Ferry Wildlife Management Area Final Draft Management Plan. March 1992.
- Casey, D. 2000. Partners in Flight Draft Bird Conservation Plan Montana. Version 1.0. 287 pp.
- Casey, D. 2004. Coordinated bird monitoring in Montana - special habitat/species monitoring: wetlands and colonial nesters. Montana Bird Conservation Partnership and University of Montana. pp 12 plus appendix.
- 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.
- Cohn, J. P. 2000. Saving the Salton Sea. BioScience 50:295-301.
- Confluence Consulting Inc. 2010. Montana Department of Transportation Wetland Mitigation Monitoring Reports (various sites). MDT Helena, MT.
- Confluence Consulting Inc. 2011. Montana Department of Transportation Wetland Mitigation Monitoring Reports (various sites). MDT Helena, MT.
- 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.
- 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.
- Ehrlich, P.R., D.S. Dobkin, and D. Wheye. 1988. The birder's handbook: a field guide to the natural history of North American birds. Simon and Shuster, Inc., New York. xxx + 785 pp.
- Findholt, S. L. and K. L. Diem. 1988. Status and distribution of American white pelican nesting colonies in Wyoming: an update. Great Basin Nat. 48:285-289.
- Gniadek, S. 1983. Southwest Glendive Wildlife Baseline Inventory. Miles City, Mont: Bureau of Land Management, Miles City District Office. 56 pp with appendices.
- Goodell, J. 2012. Morse Land Company Breeding Bird Inventory And Analysis. High Desert Museum. Bend, OR. 42 pp + Appendices.
- Johnsgard, P.A. 1979. Birds of the Great Plains: breeding species and their distribution. University of Nebraska Press, Lincoln. 539 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.
- Keith, J. O., and E. J. O'Neill. 2000. Movements of juvenile American White Pelicans from breeding colonies in California and Nevada. Waterbirds 23:33-37.
- Knopf, F.L. 1979. Spatial and temporal aspects of colonial nesting of white pelicans. Condor 81: 353-363.
- Knopf, Fritz L. and Roger M. Evans. 2004. American White Pelican (Pelecanus erythrorhynchos). Species Account Number 057. The Birds of North America Online (A. Poole, Ed.). Ithaca, NY: Cornell Laboratory of Ornithology; Retrieved 3/25/2008 from The Birds of North America Online database
- Land & Water Consulting, Inc., Missoula, MT., 2002, Montana Dept. of Transportation Wetland Mitigation Monitoring Report, Year 2001: Beaverhead Gateway, Dillon, Montana. Proj. No. 130091.011. July 2002. In 2001 Wetland Mitigation Monitoring Reports, Vol. I.
- Land & Water Consulting, Inc., Missoula, MT., 2002, Montana Dept. of Transportation Wetland Mitigation Monitoring Report, Year 2001: Cow Coulee, Townsend, Montana. Proj. No. 130091.013. July 2002. In 2001 Wetland Mitigation Monitoring Reports, Vol. I.
- Land & Water Consulting, Inc., Missoula, MT., 2002, Montana Dept. of Transportation Wetland Mitigation Monitoring Report, Year 2002: Beaverhead Gateway, Dillon, Montana. Proj. No. 130091.011. February 2003. In 2002 Wetland Mitigation Monitoring Reports, Vol. I.
- Land & Water Consulting, Inc., Missoula, MT., 2002, Montana Dept. of Transportation Wetland Mitigation Monitoring Report, Year 2002: Musgrave Lake, Zurich, Montana. Proj. No. 130091.019. May 2003. In 2002 Wetland Mitigation Monitoring Reports, Vol. II.
- Lenard, S., J. Carlson, J. Ellis, C. Jones, and C. Tilly. 2003. P. D. Skaar’s Montana bird distribution, 6th edition. Montana Audubon, Helena, MT. 144 pp.
- Lies, M. F. and W. H. Behle. 1966. Status of the White Pelican in the United States and Canada through 1964. Condor 68:279-292.
- Lumley, E. 1932. White Pelicans in Montana. Bird-Lore 34:371.
- Montana Bird Distribution Committee. 2012. P.D. Skaar's Montana bird distribution. 7th Edition. Montana Audubon, Helena, Montana. 208 pp. + foldout map.
- Palmer, R.S. 1962. Handbook of North American birds. Volume 1. Loons through flamingos. Yale University Press, New Haven. 567 pp.
- Powder River Eagle Studies, Inc., Gillette, WY., 2000, Spring Creek Mine 1999 Wildlife Monitoring. March 2000.
- Ragnal, Wendy, and Troy Brandt, Wetland Services, Helena, MT., 1998, Tucker Crossing Ranch Wetland Mitigation Project for Montana Dept. of Transportation: Highway 93 - Hamilton to Lolo: 1998 - Year Two Monitoring Report - Addendum. In Tucker Crossing Site WS# Lower Clark Fork, Ravalli County. Fin.Dist.1 Admin. Dist.1
- Root, T. L. 1988. Atlas of wintering North American birds: An analysis of Christmas Bird Count data. University of Chicago Press, Chicago. 312 pp.
- Ryder, R. A. 1981. Movements and mortality of White Pelicans fledged in Colorado. Colonial Waterbirds 4:72-76.
- Schladweiler, Philip, and John P. Weigand., 1983, Relationships of endrin and other chlorinated hydrocarbon compounds to wildlife in Montana, 1981-1982. September 1983.
- Sibley, D. 2014. The Sibley guide to birds. Alfred A. Knopf, New York, NY. 598 pp.
- Sidle, J. G., W. H. Koonz, and K. Roney. 1985. Status of the American White Pelican: An update. American Birds 39(5):859-864.
- Sidle, J.G. and E.L. Ferguson. 1984. White Pelican populations at Chase Lake, North Dakota, evaluated by aerial photography. Prairie Nat. 16: 13-26.
- Skaar, P. D., D. L. Flath, and L. S. Thompson. 1985. Montana bird distribution. Montana Academy of Sciences Monograph 3(44): ii-69.
- 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.
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- Strait, L. E., and N. F. Sloan. 1975. Movements and mortality of juvenile White Pelicans from North Dakota. Wilson Bulletin 87:54-59.
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- Thunderbird Wildlife Consulting, Inc., Gillette, WY., 2003, Spring Creek Mine 2002 Wildlife Monitoring. March 2003.
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- Vermeer, K. 1977. Comparison of White Pelican recoveries from colonies east and west of the Canadian Rocky Mountains. Murrelet 58:79-82.
- Vermeer, K. 1970. Distribution and size of colonies of White Pelicans, Pelecanus erythrorhynchos, in Canada. Canadian Journal of Zoology 48:1029-1032.
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