Index of Species Information

WILDLIFE SPECIES:  Cygnus columbianus


Introductory

WILDLIFE SPECIES: Cygnus columbianus
AUTHORSHIP AND CITATION : Tesky, Julie L. 1993. Cygnus columbianus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/ [].

ABBREVIATION : CYCO COMMON NAMES : tundra swan whistling swan Bewick's swan TAXONOMY : The currently accepted scientific name for the tundra swan is Cygnus columbianus. There are two North American subspecies: Cygnus columbianus ssp. columbianus (Ord) and C. columbianus ssp. bewickii Yarrell (Bewick's swan) [1,16]. Hybrids have occurred among captive stock between C. columbianus and the following species: Australian black swan (C. atratus), mute swan (C. olor), whooper swan (C. cygnus), trumpeter swan (C. buccinator), and Canada goose (Branta canadensis) [6]. ORDER : Anseriformes CLASS : Bird FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


WILDLIFE DISTRIBUTION AND OCCURRENCE

WILDLIFE SPECIES: Cygnus columbianus
GENERAL DISTRIBUTION : The tundra swan (C. columbianus ssp. columbianus) breeds from northern Alaska (Point Barrow and Cape Prince of Wales), south to St. Lawrence Island and the Alaska Peninsula, and east near the Arctic Coast to Baffin Island, Hudson Bay, and Churchill and the Belcher islands. Bewick's swan breeds from Russia east along the Arctic Coast to northern Siberia. It occasionally occurs in Alaska and the Pacific Northwest coast [1,6]. Cygnus columbianus ssp. columbianus winters in two regions. Populations in Alaska and Yukon Territory chiefly winter in the Central Valley of California, but some birds winter along Pacific coastal regions from southern Alaska to California and east to Utah, southern Arizona, and southern New Mexico. Tundra swans of the rest of the range migrate southwards to winter in the interior Great Lakes region or on coastal marshes from Maryland south to North Carolina, Florida, and Texas. The tundra swan occasionally winters as far north as Maine [1,8]. Bewick's swan winters in Eurasia in the British Isles, northern Europe, the Caspian Sea, Japan, Korea, and the coast of China [1]. During migration, the tundra swan (C. columbianus ssp. columbianus) occurs widely throughout interior North America on large bodies of water. It is primarily found in the Great Basin, upper Mississippi Valley, and the Great Lakes region, but also occurs in the Appalachian Mountains in southern Pennsylvania and northern West Virginia [1]. ECOSYSTEMS : FRES10 White-red-jack pine FRES11 Spruce-fir FRES17 Elm-ash-cottonwood FRES18 Maple-beech-birch FRES19 Aspen-birch FRES23 Fir-spruce FRES24 Hemlock-Sitka spruce FRES26 Lodgepole pine FRES28 Western hardwoods FRES36 Mountain grasslands FRES37 Mountain meadows FRES38 Plains grasslands FRES39 Prairie STATES :
AK AZ AR CA CO DE ID
IA MD MI MN MO MT NJ
NM NY NC ND OH OR PA
SC SD TX UT VA WA WI WY

AB BC MB NT ON PE PQ SK YK
BLM PHYSIOGRAPHIC REGIONS : 1 Northern Pacific Border 2 Cascade Mountains 3 Southern Pacific Border 4 Sierra Mountains 5 Columbia Plateau 6 Upper Basin and Range 7 Lower Basin and Range 8 Northern Rocky Mountains 9 Middle Rocky Mountains 10 Wyoming Basin 11 Southern Rocky Mountains 12 Colorado Plateau 13 Rocky Mountain Piedmont 16 Upper Missouri Basin and Broken Lands KUCHLER PLANT ASSOCIATIONS : K001 Spruce - cedar - hemlock forest K008 Lodgepole pine - subalpine forest K015 Western spruce - fir forest K020 Spruce - fir - Douglas-fir forest K021 Southwestern spruce - fir forest K025 Alder - ash forest K063 Foothills prairie K064 Grama - needlegrass - wheatgrass K093 Great Lakes spruce - fir forest K094 Conifer bog K095 Great Lakes pine forest K106 Northern hardwoods K107 Northern hardwoods - fir forest K108 Northern hardwoods - spruce forest SAF COVER TYPES : 16 Aspen 204 Black spruce 217 Aspen 218 Lodgepole pine 222 Black cottonwood - willow 223 Sitka spruce 225 Western hemlock - Sitka spruce 235 Cottonwood - willow SRM (RANGELAND) COVER TYPES : NO-ENTRY PLANT COMMUNITIES : Tundra swans are generally found in wetland areas among aquatic and emergent vegetation. They are commonly found feeding in extensive beds of pondweeds (Potamogeton spp.) [10]. Other plant species found in wetland areas occupied by tundra swans include willows (Salix spp.), wild celery (Valisineria americana), smartweed (Polygonum persicaria), muskgrasses (Characeae spp.), bulrushes (Scirpus spp.), horsetail (Equisetum spp.), and sedges (Carex spp.) [10]. REFERENCES : NO-ENTRY

BIOLOGICAL DATA AND HABITAT REQUIREMENTS

WILDLIFE SPECIES: Cygnus columbianus
TIMING OF MAJOR LIFE HISTORY EVENTS : Age at first breeding - Tundra swans first breed when they are 2 or 3 years old. They form lifelong monogamous pairs [10]. Nesting - Tundra swans start nesting in late May to late June depending on location and weather [2,10]. Clutch size and incubation - Tundra swans generally lay a clutch of four or five eggs [6,10]. The incubation period is 30 to 32 days [10]. Cygnet development and fledging - Tundra swan cygnets are generally able to fly within 9 to 10 weeks. The family remains together during the fall migration, through winter, and during spring migration [10]. Molt - On the Yukon Delta, adult tundra swans molt between July and August and regain flight within 35 to 40 days. Nonbreeders, which remain in flocks of 3 to 15 during the breeding season, regain flight in late August and begin to congregate in sizable flocks [2]. Fall migration - Tundra swans migrate in family units, with several families and probably some nonbreeding birds combining in a single flock [2]. In the West, tundra swans leave major breeding grounds in Alaska in late September and early October. Marshes adjoining the eastern shore of Great Salt Lake begin to receive tundra swans in mid-October. Tundra swans begin arriving at the Malheur National Wildlife Refuge in Oregon from mid- to late November and remain abundant well into December. In the Klamath basins of Oregon and California, wintering tundra swans do not arrive in substantial numbers until late November and early December. On winter grounds adjacent to San Francisco Bay, the swans are not present in great numbers until early December [2]. The eastern contingent of tundra swans passes across Minnesota, Wisconsin, and Michigan, largely during November 5 to 15. Tundra swans on Chesapeake Bay slowly increase in numbers through December and reach a peak in January [2]. Spring migration - Tundra swans begin leaving their winter habitat after the first spring thaw [2]. Tundra swans from Chesapeake Bay cross Pennsylvania to Lake Erie from the first week in March into early April. Tundra swans leave their central California winter grounds in mid-February, and within 3 weeks almost all have departed. By early April most have migrated north to Alaska and Canada. The first swans generally reach their breeding grounds on the Yukon Delta in late April and almost all arrive by mid-May. The western population of tundra swans migrate earlier and more swiftly than its eastern counterpart [2]. PREFERRED HABITAT : Breeding habitat - Tundra swans usually breed on or near tundra ponds, lakes, and sluggish rivers, and less often near sheltered tidal waters. They tend to avoid areas near exposed marine coasts [1,8,10]. Nest sites - Tundra swans often select islets in tundra ponds and lakes as nest sites [10]. Nests are also commonly located on the main shores of lakes or ponds, heath tundras, hummocks in marshes or tidal meadows, or more rarely, level stretches in marsh or meadow areas [2,15]. The nest is an elaborate platform, 12 to 18 inches (30-45 cm) high, composed of mosses, grasses, and sedges. It resembles a muskrat house surrounded by a moat. In making the nest, the vegetation is plucked from around the nest site, creating a circle of open water up to 15 feet (4.6 m) in diameter [2]. In optimum habitat, several pairs of swans may have nests very widely spaced but still in view of one onother [10]. Winter habitat - In winter, tundra swans use extensive shallow fresh and brackish water. They are less frequently found on salt water. Migrants occur at ponds, lakes, flooded lowlands, slow-moving streches of rivers, and estuaries [8,10]. COVER REQUIREMENTS : Tall emergent vegetation provides shelter and cover for tundra swans. Adult swans remove vegetation around the nest until the nest is surrounded by open water [2,10]. FOOD HABITS : Tundra swans eat the stems, seeds, and bulbous roots of aquatic plants, and the seeds and young shoots of cultivated grains. They also eat a small amount of animal matter consisting mainly of the larvae of aquatic beetles and dragon flies, worms, and mollusks [2,10]. Tundra swans feed on the following plants: foxtail (Alopecurus spp.) and other grasses, wild celery, pondweeds, smartweeds, square-stem spike rush (Eleocharis quadrangulata), arrowhead (Sagittaria spp.), coontail (Ceratophyllum demersum), mermaid weed (Prosperinaca spp.), muskgrasses, bulrushes, horsetail, wigeon grass (Ruppia maritima), and bur reed (Sparganium spp.). Rice and barley are eaten in stubble fields [2,10]. Tundra swans also feed on waste corn in both dry and flooded fields and upon harvested potatoes. These swans commonly fly as far as 10 to 15 miles (16-24 km) inland to glean waste corn and soybeans and to browse upon shoots of winter wheat [2]. PREDATORS : Little information is available in the literature regarding predation on tundra swans. Bellrose [2] reported that nests have been destroyed by gulls (Larus spp.) and foxes. The following species also occur in tundra swan habitat and could potentially prey on tundra swans: coyotes (Canis lutrans), river otters (Lutra canadensis), minks (Mustela vison), black bears (Ursus americanus), grizzly bears (U. arctos), bald eagles (Haliaetus leucocephalus), mountain lions (Felis concolor), skunks (Mephitis spp. and Spilogale spp.), and raccoons (Procyon lotor). In a few states, experimental hunting of tundra swans is allowed. Generally, a one swan per hunter limit is imposed [10]. Taking of tundra swan eggs and the hunting of flightless molting birds by Native Americans are significant mortality factors in some areas [10]. MANAGEMENT CONSIDERATIONS : The tundra swan is the most common and widespread swan in North America [15]. Winter surveys of tundra swans during the 1950's in the United States revealed an average population of 78,000. This figure increased to 98,000 during the 1960's and to 133,000 during 1970-74. The lowest population recorded from 1949 to 1974 was in 1950 at 49,000, and the highest was 157,000 in January 1971. Although the number of tundra swans found on the winter surveys has varied considerably from year to year, there has been a slow increase in the continental population over the last 25 years [2]. REFERENCES : NO-ENTRY

FIRE EFFECTS AND USE

WILDLIFE SPECIES: Cygnus columbianus
DIRECT FIRE EFFECTS ON ANIMALS : No specific information was found in the literature regarding the direct effects of fire on tundra swans. However, adult nonmolting tundra swans can probably easily escape fire. Molting adults, nests, and cygnets are probably most susceptible to fire. HABITAT RELATED FIRE EFFECTS : Fire occurring in wetland habitats often removes excessive accumulations of fast-growing hydrophytes, permitting better waterfowl access, more feeding and loafing areas, and growth of more desirable tundra swan foods such as pondweeds [11,12]. In the Nebraska sandhills many desirable plants for waterfowl, such as duckweeds (Lemna spp.), pondweeds, and wild rice (Zizania spp.) become more abundant following fire because more open water is created [11]. There may be some negative effects of burning waterfowl habitat. Large-scale autumn burning may have a detrimental effect upon marshes by reducing the retention of drifting snow. The ability of marsh vegetation to catch and hold snow is vital to marsh survival [13]. FIRE USE : Prescribed burning is an effective method of manipulating waterfowl habitat [11,14]. Fire can be used to convert forested uplands adjacent to aquatic habitats to grasses and sedges, which are more suitable for tundra swan nesting. Additionally, removal of dense vegetation and prevention of woody encroachment is vital to prairie marsh maintenance [12]. Less dense vegetation allows space for waterfowl movement and activities [11]. According to Ward [13], spring burning in marshlands is primarily done to remove vegetation and create more nesting edge for waterfowl. Summer fires are used to create more permanent changes in the plant community [13]. Prescribed burning during the nesting season should be avoided so as not to disturb nesting females and/or destroy nests and cygnets. REFERENCES : NO-ENTRY

REFERENCES

WILDLIFE SPECIES: Cygnus columbianus
REFERENCES : 1. American Ornithologists' Union. 1983. Checklist of North American birds. 6th ed. Lawrence, KS: Allen Press, Inc. 877 p. [21234] 2. Bellrose, Frank C. 1980. Ducks, geese and swans of North America. Harrisburg, PA: Stackpole Books. 3rd ed. 540 p. [19802] 3. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. [434] 4. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905] 5. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. [998] 6. Johnsgard, Paul A. 1979. A guide to North American waterfowl. Bloomington, IN: Indiana University Press. 274 p. [20026] 7. Kortright, Francis H. 1942. The ducks, geese and swans of North America. Harrisburg, PA: The Stackpole Company; Washington, DC: Wildlife Management Institute. 476 p. [21240] 8. Madge, Steve; Burn, Hilary. 1988. Waterfowl: An indentification guide to the ducks, geese and swans of the world. Boston, MA: Houghton Mifflin Company. 298 p. [20029] 9. Musgrove, Jack W.; Musgrove, Mary R. 1943. Waterfowl in Iowa. Des Moines, IA: State Convservation Committee. 113 p. + index. [20028] 10. Palmer, Ralph S., editor. 1976. Handbook of North American birds. vol. 2. New Haven, CT: Yale University Press. 521 p. [21242] 11. Schlichtemeier, Gary. 1967. Marsh burning for waterfowl. In: Proceedings, 6th annual Tall Timbers fire ecology conference; 1967 March 6-7; Tallahassee, FL. No. 6. Tallahassee, FL: Tall Timbers Research Station: 40-46. [16450] 12. Vogl, Richard J. 1967. Controlled burning for wildlife in Wisconsin. In: Proceedings, 6th annual Tall Timbers Fire Ecology Conference; 1967 March 6-7; Tallahassee, FL. No. 6. Tallahassee, FL: Tall Timbers Research Station: 47-96. [18726] 13. Ward, P. 1968. Fire in relation to waterfowl habitat of the delta marshes. In: Proceedings, annual Tall Timbers fire ecology conference; 1968 March 14-15; Tallahassee, FL. No. 8. Tallahassee, FL: Tall Timbers Research Station: 255-267. [18932] 14. Wright, Henry A.; Bailey, Arthur W. 1982. Fire ecology: United States and southern Canada. New York: John Wiley & Sons. 501 p. [2620] 15. DeGraaf, Richard M.; Scott, Virgil E.; Hamre, R. H.; [and others]. 1991. Forest and rangeland birds of the United States: Natural history and habitat use. Agric. Handb. 688. Washington, DC: U.S. Department of Agriculture, Forest Service. 625 p. [15856] 16. Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation of the conterminous United States. Special Publication No. 36. New York: American Geographical Society. 77 p. [1384] 17. American Ornithologists' Union. 1957. Checklist of North American birds. 5th ed. Baltimore, MD: The Lord Baltimore Press, Inc. 691 p. [21235]


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