Index of Species Information



AUTHORSHIP AND CITATION : Snyder, S. A. 1993. Aix sponsa. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].

ABBREVIATION : AISP COMMON NAMES : wood duck TAXONOMY : The currently accepted scientific name for wood duck is Aix sponsa Linnaeus [1]. There are no recognized subspecies [5]. ORDER : Anseriformes CLASS : Bird FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


GENERAL DISTRIBUTION : The wood duck's breeding range includes most of the states and the southern portions of the provinces of North America. Populations are scarce in the western interior states, especially Utah, Arizona, and New Mexico [5]. Breeding densities are highest in the Mississippi River valleys [2,5]. In winter, wood ducks are found on the West Coast from southern British Columbia to southern California, and on the eastern coasts from southern New Jersey to southern Florida and west to central Texas. Winter densities are high in California's Central Valley and the southern states of the Mississippi and Atlantic flyways [5]. The Atlantic population is distributed throughout the Atlantic Flyway states and in southeastern Canada. The Interior population is found on the Mississippi Flyway, parts of Ontario, and the eastern tier of states in the Central Flyway. The Pacific population is distributed from British Columbia south to California and east to western Montana [5]. ECOSYSTEMS : FRES10 White-red-jack pine FRES11 Spruce-fir FRES12 Longleaf-slash pine FRES13 Loblolly-shortleaf pine FRES14 Oak-pine FRES15 Oak-hickory FRES16 Oak-gum-cypress FRES17 Elm-ash-cottonwood FRES18 Maple-beech-birch FRES19 Aspen-birch FRES20 Douglas-fir FRES21 Ponderosa pine FRES22 Western white pine FRES25 Larch FRES26 Lodgepole pine FRES27 Redwood FRES28 Western hardwoods STATES :


BLM PHYSIOGRAPHIC REGIONS : 1 Northern Pacific Border 2 Cascade Mountains 3 Southern Pacific Border 4 Sierra Mountains 5 Columbia Plateau 8 Northern Rocky Mountains 9 Middle Rocky Mountains 14 Great Plains 16 Upper Missouri Basin and Broken Lands KUCHLER PLANT ASSOCIATIONS : K005 Mixed conifer forest K006 Redwood forest K008 Lodgepole pine - subalpine forest K011 Western ponderosa forest K012 Douglas-fir forest K013 Cedar - hemlock - pine forest K014 Grand fir - Douglas-fir forest K015 Western spruce - fir forest K018 Pine - Douglas-fir forest K020 Spruce - fir - Douglas-fir forest K091 Cypress savanna K092 Everglades K093 Great Lakes spruce - fir forest K095 Great Lakes pine forest K097 Southeastern spruce - fir forest K098 Northern floodplain forest K099 Maple - basswood forest K100 Oak - hickory forest K101 Elm - ash forest K102 Beech - maple forest K103 Mixed mesophytic forest K104 Appalachian oak forest K106 Northern hardwoods K107 Northern hardwoods - fir forest K108 Northern hardwoods - spruce forest K110 Northeastern oak - pine forest K111 Oak - hickory - pine forest K112 Southern mixed forest K113 Southern floodplain forest SAF COVER TYPES : 1 Jack pine 14 Northern pin oak 15 Red pine 16 Aspen 21 Eastern white pine 25 Sugar maple - beech - yellow birch 26 Sugar maple - basswood 27 Sugar maple 28 Black cherry - maple 39 Black ash - American elm - red maple 40 Post oak - blackjack oak 42 Bur oak 52 White oak - black oak - northern red oak 53 White oak 55 Northern red oak 59 Yellow-poplar - white oak - northern red oak 60 Beech - sugar maple 61 River birch - sycamore 62 Silver maple - American elm 63 Cottonwood 64 Sassafras - persimmon 65 Pin oak - sweetgum 70 Longleaf pine 75 Shortleaf pine 80 Loblolly pine - shortleaf pine 81 Loblolly pine 84 Slash pine 88 Willow oak - water oak - diamondleaf oak 91 Swamp chestnut oak - cherrybark oak 92 Sweetgum - willow oak 93 Sugarberry - American elm - green ash 94 Sycamore - sweetgum - American elm 95 Black willow 96 Overcup oak - water hickory 101 Baldcypress 108 Red maple 110 Black oak 111 South Florida slash pine 210 Interior Douglas-fir 212 Western larch 213 Grand fir 215 Western white pine 217 Aspen 218 Lodgepole pine SRM (RANGELAND) COVER TYPES : NO-ENTRY PLANT COMMUNITIES : Wood ducks inhabit mostly forested wetland communities, such as southern and central floodplain forests, red maple (Acer rubrum) swamps, temporarily flooded oak (Quercus spp.)-hickory (Carya spp.) forests, and northern bottomland hardwood sites [13]. REFERENCES : NO-ENTRY


TIMING OF MAJOR LIFE HISTORY EVENTS : Courting- before fall migration and again in spring Age of Maturity- 1 year Nesting- late January (South); early March (Midwest); March-April (North) Clutch- 7 to 15 eggs; average 12; some females deposit eggs in another female's nest (called "dumping") Incubation- 26 to 37 days Fledging- 56 to 70 days Migration- some southern residents are year-round; northern populations head south in late September and north in late February [5] PREFERRED HABITAT : Wood ducks prefer wooded wetlands and forests with small lakes, ponds, or riparian corridors, and flooded forested bottomlands. They nest in tree cavities or man-made boxes, usually within 0.6 miles (1 km) from water [5]. They prefer riparian areas with a large amount of shoreline per unit area of water, and with the opposite shore at least 100 feet (30 km) away [13]. In the Mississippi River valleys, chicks prefer water sites where currents are less than 1 mile per hour (1.6 km/h). Chicks less than 2 weeks old use flooded lowland forests, while older chicks use shrub communities [13]. Breeding and brooding hens prefer sites with ratios of 50 to 75 percent cover:25 to 50 percent open water. Detailed habitat suitability index models have been developed for wood ducks [13]. Wood duck preference for trees used for cavity nesting have been listed in order of descending importance. In floodplain forests these are baldcypress (Taxodium distichum), sycamore (Platanus spp.), silver maple (Acer saccharinum), black ash (Fraxinus nigra), sourgum (Nyssa spp.), and black willow (Salix nigra). On upland areas these are black oak (Quercus velutina), red oak (Q. rubra), white oak (Q. alba), blackjack oak (Q. marilandica), bur oak (Q. macrocarpa), and basswood (Tilia americana) [2]. A study in northcentral Minnesota identified 31 wood duck nest cavities and found that 21 of these were in mature (60-75 years) quaking aspen (Populus tremuloides) stands, while the rest were in mature (100-120 years) mixed hardwood stands. Nest sites were within 1,150 feet (350 m) of water, and entrance holes were not less than 12 feet (4 m) above ground [8]. COVER REQUIREMENTS : Wood ducks prefer sites with nest cavities within 0.3 miles (0.5 km) of water, but will nest more than 0.6 miles (1 km) from cover if necessary. Nest cavity trees must have a d.b.h. of greater than 12 inches (30 cm). The nest entrance hole should be at least 6 feet (2 m) above ground, and greater than 3.5 inches (8.9 cm) in diameter. The interior basal area should be greater than 40 inches squared (258 cm sq) [5]. Water depths are important in brooding and breeding habitat from mid-April to late September in the North and mid-January to late September in the South. In breeding habitat, depth should be 3 to 18 inches (7.5-45 cm), and banks should be sheltered with shrubs. In brooding habitat, chicks need a water depth of less than 12 inches (30 cm) so they can forage for invertebrates [13]. Ideal cover for wood ducks is provided by shrubs that hang in a dense canopy about 2 feet (6 m) above the water surface. Downed timber can provide year-round cover. Habitat consisting of downed timber, woody and herbaceous plants, and interspersed water channels provides good brood cover [13]. Optimum cover for brooding consists of 30 to 50 percent shrubs, 40 to 70 percent emergent plants, up to 10 percent trees, and 25 percent open water [13]. FOOD HABITS : The majority of wood duck food consists of plant material, with a supplement of invertebrates. During winter almost 100 percent of the diet is plants, with an increase in animal protein (35 percent) in early spring [5]. These percentages remain constant for males during the summer and fall molts, but increase for females to about 80 percent animal protein during egg laying. This percentage drops for females during incubation, when their diet includes high-energy seeds. Wood ducks usually will not forage in agricultural fields as long as their native food sources are plentiful [13]. Some plant foods of wood ducks include fruits of maples (Acer spp.), oaks, ash (Franius spp.), sassafras (Sassafras albidum), sweetgum (Liquidambar styraciflua), baldcypress, water hickory (Carya aquatica), buttonbush (Cephalanthus occidentalis), Asiatic dayflower (Aneilema keisak), watershield (Brassenia schreberi), barnyard grass (Echinochloa spp.), rice cutgrass (Leersia oryzoides), primrose willow (Ludwigia leptocarpa), white waterlily (Nymphaea odorata), panicum (Panicum spp.), smartweeds (Polygonum spp.), pondweeds (Potamogeton spp.), water bulrush (Scirpus subterminalis), and slough grass (Sclera reticularis). Invertebrate foods include spiders, crayfish, midges, scuds, water boatmen, sowbugs, damselflies, dragonflies, caddis flies, and orb snails [5,13]. PREDATORS : Wood duck predators include humans, mink (Mustela vison), raccoon (Procyon lotor), fox squirrel (Sciurus niger), bullfrog (Rana catesbeiana), snapping turtle (Chelydra serpentina), largemouth bass (Micropterus floridanus), crows (Corvidae spp.), and starling (Sturnus vulgaris) [2,5]. MANAGEMENT CONSIDERATIONS : Overmature trees and snags should be left on logging sites for wood duck nesting cavities. Mixed stands of trees, including those producing mast and/or providing nesting cavities, should be left on these sites. Elm (Ulmus spp.) and maple are an important component of wood dick habitat because they provide both [5]. Nest boxes constructed of wood, metal, or plastic can be used in areas where cavities are limited. If placed in direct sunlight, however, plastic or metal may reach internal temperatures high enough to kill embryos. For detailed information on constructing nest boxes, refer to the U.S. Fish and Wildlife Service [14]. In bottomland hardwood sites where flooding is controlled, it is important to maintain a flooding regime that promotes oaks that bear small acorns. Overcup oak (Quercus lyrata) produces large acorns which are usually unsuitable as wood duck food [5]. Water depths in foraging areas should be maintained at levels less than 8 inches (20 cm), but can be deeper in resting and roosting sites. Detailed information for managing flood-controlled wetlands for wildlife habitat across the United States is available [4]. Bottomland hardwood sites need openings to increase the growth of mast- producing oaks. Their growth is stunted under closed canopies [11]. Openings can be created by thinning or select cutting. Long-term studies indicate that growth of trees on greentree reservoir sites (GTRs) is reduced by several years of flooding. However, there is no indication that this poses any threat to wildlife, such as wintering wood ducks, that use GTRs. Flooding GTRs is recommended from mid-September in the North and continuing through mid- to late October in the South. Drawdown should begin in mid-February [11]. REFERENCES : NO-ENTRY


DIRECT FIRE EFFECTS ON ANIMALS : NO-ENTRY HABITAT RELATED FIRE EFFECTS : Specific information regarding the effects of fire on wood duck habitat has not been found. The author concludes that because wood ducks need forested wetlands for cover and food, fires that substantially remove overstory, especially that providing nesting cavities and mast, could harm wood duck populations. Hydric hammock communities in the South, which support wintering wood ducks, are not as fire-dependent or adapted as neighboring pine flatwood communities [15]. Some tree species in these hydric hammock communities can be damaged by fire, thus becoming susceptible to fungal attack and decay. Red oak swamps are important for wintering wood ducks. Red oak is more susceptible to fire than many other oak species (see FEIS DATABASE: Quercus rubra). Severe fire may kill seedlings and sawtimber-sized red oak; however, larger red oak sprout from the root crown and/or trunk following such fire. FIRE USE : Fire is NOT recommended to rejuvenate elm-ash-cottonwood stands in bottomlands of the north-central United States. These genera, and others in this type, are susceptible to fire damage. Fires could lead to loss of the bottomland hardwood stand, which is important wood duck habitat [12]. REFERENCES : NO-ENTRY

References for species: Aix sponsa

1. American Ornithologists' Union. 2004. The A.O.U. check-list of North American birds, 7th edition, [Online]. American Ornithologists' Union (Producer). Available: [2005, January 10]. [50863]
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. Cross, Diana H. 1988. Waterfowl management guidebook. Washington, DC: U.S. Department of the Interior, Fish and Wildlife Service. [Pages unknown]. [21574]
5. Dugger, Katie M.; Fredrickson, Leigh H. 1992. Life history and habitat needs of the wood duck. Fish and Wildlife Leaflet 13.1.6. Waterfowl Management Handbook. Washington, DC: U.S. Department of the Interior, Fish and Wildlife Service. 8 p. [20789]
6. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905]
7. 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]
8. Gilmer, David S.; Ball, I. J.; Cowardin, Lewis M.; [and others]. 1978. Natural cavities used by wood ducks in north-central Minnesota. Journal of Wildlife Management. 42(2): 288-298. [13749]
9. Hepp, Gary R.; Hines, James E. 1991. Factors affecting winter distribution and migration distance of wood ducks from southern breeding populations. The Condor. 93: 884-891. [20662]
10. 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]
11. Moorhead, David J.; Hodges, John D.; Reinecke, Kenneth J. 1991. Silvicultural options for waterfowl management in bottomland hardwood stands and greentree reservoirs. In: Coleman, Sandra S.; Neary, Daniel G., compilers. Proceedings, 6th biennial southern silvicultural research conference: Volume 2; 1990 October 30 - November 1; Memphis, TN. Gen. Tech. Rep. SE-70. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southeastern Forest Experiment Station: 710-721. [17507]
12. Myers, Charles C.; Buchman, Roland G. 1984. Manager's handbook for elm-ash-cottonwood in the North Central States. Gen. Tech. Rep. NC-98. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station. 11 p. [8919]
13. Sousa, P. J.; Farmer, A. H. 1983. Habitat suitability index models: wood duck. FWS/OBS-82/10.43. Washington, DC: U.S. Department of the Interior, Fish and Wildlife Service. 27p. [29456]
14. U.S. Department of the Interior, Fish and Wildlife Service. 1976. Nest boxes for wood ducks. Wildlife Leaflet No. 510. Washington, DC. 14 p. [21465]
15. Vince, Susan W.; Humphrey, Stephen R.; Simons, Robert W. 1989. The ecology of hydric hammocks: A community profile. Biological Rep. 85(7.26). Washington, DC: U.S. Department of the Interior, Fish and Wildlife Service, Research and Development. 82 p. [17976]
16. Vince, Susan W.; Humphrey, Stephen R.; Simons, Robert W. 1989. The ecology of hydric hammocks: A community profile. Biological Rep. 85(7.26). Washington, DC: U.S. Department of the Interior, Fish and Wildlife Service, Research and Development. 82 p. [17977]