Behavior

Walking, Hopping, Climbing

Wood Ducks walk with a fast gait, more erect than dabbling ducks; often feed on land near water's edge. Females frequently move with young over land to brood-rearing areas. Partially grown young have been timed at 8.9-11.4 km/h (Stewart 1958a Stewart, P. A. (1958a). Local movements of Wood Ducks. Auk 75:157-168. Close ). Birds commonly perch and walk on branches, especially when searching for nest site. Ducklings are adept at walking, hopping, and climbing when leaving nest cavity; nesting adults probably are also to some extent.

Flight

Rises quickly from water with rapid wingbeat. Maneuvers well flying through thick woods. Flight speed of 51 km/h recorded in migration (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Swimming And Diving

Adults and young are excellent swimmers; occasionally dive for food but seldom deeper than 1 m. Young birds escape disturbance and predators by diving. When diving, advanced ducklings and adults are observed using the partial opening and closing of wings and feet to swim underwater (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Preening, Head-Scratching, Stretching, Bathing, Anting, Etc

Not known to ant. Other activities are done throughout the year; by mated pairs, almost twice as frequently in midday as in morning or afternoon (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Sleeping, Roosting

Sleeps primarily on water, secondarily on logs, banks, muskrat (Ondatra zibethicus) houses. Females with young broods sleep out of water, preferably on logs. Wood Ducks congregate in the evening at roosting areas; peak numbers occur in fall (Bellrose 1976a Bellrose, F. C. (1976). Ducks, Geese and Swans of North America. Second edition. Stackpole Books, Harrisburg, PA, USA. Close ). Roosting aggregations sometimes number a few thousand. Roosts typically are located in shallow forested or scrub/shrub wetlands with dense cover (Luckett and Hair 1979 Luckett, L. M. and J. D. Hair. (1979). Analysis of Wood Duck roost counts in northwest South Carolina. Proceedings of the Southeastern Association of Fish and Wildlife Agencies 33:96-103. Close , Kirby and Fredrickson 1990 Kirby, R. E. and L. H. Fredrickson. (1990). "Molts and plumages of the Wood Duck." In Proc. 1988 N. Am. Wood Duck symp., edited by L. H. Frederickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 29-33. St. Louis, MO. Close ).

Daily Time Budgets

Few data; dense cover makes birds difficult to observe. In Missouri, breeding females spent more time feeding (73%) than males (34%), but about the same amount of time was spent by males (22%) and females (27%) in maintenance activities (i.e., sleeping, loafing, swimming, and comfort movements); males spent the remainder of their time (44%) alert (Drobney and Fredrickson 1979 Drobney, R. D. and L. H. Fredrickson. (1979). Food selection by Wood Ducks in relation to breeding status. Journal of Wildlife Management 43:109-120. Close ). In Illinois, Bellrose and Holm (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ) also reported that prelaying, mated pairs differed in time spent in various activities. Females spent more time feeding than males: 34 and 23%, respectively. Time spent swimming and/or walking was similar for females (21%) and males (24%). Males spent more time alert (16%) than females (8%), but time spent in maintenance activities was the same for the sexes (8%).

Physical Interactions

Defense of mates by males sometimes includes chasing, pecking, and hitting with opened wings when other males approach too closely (Korschgen and Fredrickson 1976 Korschgen, C. E. and L. H. Fredrickson. (1976). Comparative displays of yearling and adult male Wood Ducks. Auk 93:793-809. Close ). When several males persist in courting a paired female, aggressive interactions ensue between unpaired and paired males. Feathers may be grabbed in various areas from head to tail, and wings frequently are used to strike opponents. Such bouts rarely last more than a moment before the intruder gives up and swims away (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Extreme agonistic behavior has been reported at Navoo, IL, among breeding females using nest boxes (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ). Interactions between resident and intruding females resulted in the death of 28 females and head injuries to 37 of the 1,479 females laying in nest boxes. Usually the intruding female was killed or maimed by the dominant bird grasping the head with mandibles and twisting the scalp or depressing the skull. High nesting density (46-47 pairs/5.5 ha) is thought to have caused the aggression; none reported from other locations, despite many breeding studies (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Communicative Interactions

Bill-jerk, a rapid upward jerking of the bill; Bill-jab, a rapid jabbing of the bill; and Inciting are used as threat displays by males and females (Johnsgard 1965 Johnsgard, P. A. (1965). Handbook of Waterfowl Behavior. Cornell University Press, Ithaca, New York, USA. Close , Armbruster 1982 Armbruster, J. S. (1982). Wood Duck displays and pairing chronology. Auk 99:116-122. Close ). Bill Open with neck stretched and head down also is used as threat display.

Territoriality

Not territorial, but male will defend his mate when approached too closely, resulting in a small moving territory (Grice and Rogers 1965 Grice, D. and J. P. Rogers. (1965). The Wood Duck in Massachusetts. Westboro, MA: Mass. Div. Fish and Game. Close , Jones and Leopold 1967 Jones, R. E. and A. S. Leopold. (1967). Nesting interference in a dense population of Wood Ducks. Journal of Wildlife Management 31:221-228. Close ). Lack of territoriality may be an adaptation to breeding in habitats with fluctuating water levels where temporal and spatial distribution of food may vary (Fredrickson and Graber 1990 Fredrickson, L. H. and D. A. Graber. (1990). "Habitat ecology and management." In Proc. 1988 N. Am. Wood Duck symp., edited by L. H. Frederickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 381-385. St. Louis, MO. Close ). Because nest site is not defended, breeding-pair densities often are high when nest boxes are provided in a clumped distribution (Haramis 1990 Haramis, G. M. (1990). "Breeding ecology of the Wood Duck: a review." In Proc. 1988 N. Am. Wood Duck symp., edited by L. H. Frederickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 45-60. St. Louis, MO. Close ).

No feeding territories in fall or spring; pairs of birds feed close together without interaction (Drobney and Fredrickson 1979 Drobney, R. D. and L. H. Fredrickson. (1979). Food selection by Wood Ducks in relation to breeding status. Journal of Wildlife Management 43:109-120. Close ). No information on dominance hierarchies; if similar to other ducks, then males are dominant to females and adults are dominant to young (Hepp 1986 Hepp, G. R. (1986). Effects of body weight and age on the time of pairing of American Black Ducks. Auk 103:477-484. Close ).

Mating System And Sex Ratio

Monogamous. Because of long breeding seasons (5-6 mo) and no male care of young, males may be serially monogamous at southern latitudes (Fredrickson and Graber 1990 Fredrickson, L. H. and D. A. Graber. (1990). "Habitat ecology and management." In Proc. 1988 N. Am. Wood Duck symp., edited by L. H. Frederickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 381-385. St. Louis, MO. Close ). Sex ratio is 1:1 at hatching (GRH). In fall, Atlantic Flyway has 56% males, Mississippi Flyway 54% males (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ). Banding in winter revealed 57% males (Henny 1970 Henny, C. J. (1970). Winter bandings of Mallards, Black Ducks, Wood Ducks, Pintails, Canvasbacks, Redheads, and Scaup in 1967, 1968, and 1969. Washington, D.C: Bur. Sport Fish and Wildl. Adm. Close ). Hunters select males, but females are vulnerable to predators while nesting, resulting in sex ratio skewed to males.

Pair Bond

In Illinois, more courtship is observed in fall than spring, indicating that much of population forms pairs in fall and winter (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ). Pair bonds probably maintained through incubation early in breeding season, but may cease midincubation or earlier as season progresses (Bellrose 1976a Bellrose, F. C. (1976). Ducks, Geese and Swans of North America. Second edition. Stackpole Books, Harrisburg, PA, USA. Close , Fredrickson and Graber 1990 Fredrickson, L. H. and D. A. Graber. (1990). "Habitat ecology and management." In Proc. 1988 N. Am. Wood Duck symp., edited by L. H. Frederickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 381-385. St. Louis, MO. Close ). Courtship displays are described by Heinroth (Heinroth 1910 Heinroth, O. (1910). Beobachtungen bei einen Einburgerungsversuch mit der Brautente (Lampronessa sponsa (L.)). Journal of Ornithology 58:101-156. Close ), Lorenz (Lorenz 1941b Lorenz, K. (1941b). Comparative studies on the behavior of Anatinae. Journal of Ornithology 84:194-294. Close ), Johnsgard (Johnsgard 1965 Johnsgard, P. A. (1965). Handbook of Waterfowl Behavior. Cornell University Press, Ithaca, New York, USA. Close ), Korschgen and Fredrickson (Korschgen and Fredrickson 1976 Korschgen, C. E. and L. H. Fredrickson. (1976). Comparative displays of yearling and adult male Wood Ducks. Auk 93:793-809. Close ), and Bellrose and Holm (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Courtship Displays

Turn-the-back-of-the-head. Figure 3B . Female may or may not Incite (see below) as male swims in front of her while performing this display. Wings and tail are held high; tail is tilted away from female. Most common display noted by Korschgen and Fredrickson (Korschgen and Fredrickson 1976 Korschgen, C. E. and L. H. Fredrickson. (1976). Comparative displays of yearling and adult male Wood Ducks. Auk 93:793-809. Close ); apparently functions to strengthen pair bond. Combination of Inciting by female and Turn-the-back-of-the-head by male is the most important display in pair-bond maintenance (Johnsgard 1965 Johnsgard, P. A. (1965). Handbook of Waterfowl Behavior. Cornell University Press, Ithaca, New York, USA. Close ).

Chin-lift. Performed alone or in combination with Turn-the-back-of-the-head. Head is held tilted slightly back for several seconds, exposing white chin to female

Drinking. Ritualized; occurs frequently during courtship. Similar to regular drinking, but lifting of head is slightly exaggerated. Always precedes Preen-behind-the-wing.

Preen-behind-the-wing. Begins when male stops moving; crest is partially erected, head low, and bill resting on breast. Male drinks; moves head laterally very quickly as he points bill toward female. Male lifts wing nearest female, spreads primaries and secondaries, and preens. Usually performed in front of and perpendicular to female. Sometimes performed by females to their mates as they rest or preen. Display is not observed during mate selection; may function mainly to strengthen and maintain pair bonds (Korschgen and Fredrickson 1976 Korschgen, C. E. and L. H. Fredrickson. (1976). Comparative displays of yearling and adult male Wood Ducks. Auk 93:793-809. Close ).

Display Shake. A ritualized general shake combined with whistling note; analogous to Grunt-whistle of Anas. Considered to be the most elaborate of courtship displays. As display begins, male erects crest, extends and lowers head, and raises breast, exposing white belly. He then moves head quickly up and back. Head is high with bill pointing down and chin touching neck, breast high out of water. Display ends when body is lowered to normal swimming position.

Wing-and-tail Flash. Figure 3A . Performed only by Wood and Mandarin ducks (Johnsgard 1965 Johnsgard, P. A. (1965). Handbook of Waterfowl Behavior. Cornell University Press, Ithaca, New York, USA. Close ). Analogous to Head-up-tail-up Display given by male dabbling ducks. Closed wing and tail are raised rapidly as male orients broadside to female. Crest is erect and bill tipped down, exposing entire crest. Both paired and unpaired males perform this display; it probably functions to establish and maintain pair bond (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Burp. Whistle (pfit) by male is accompanied by vertical stretching of neck and raising of crest. Begins with a quick lateral head shake in which bill is pointed toward female. Functions primarily in pair-bond maintenance.

Bill-jerk. Consists of rapid, upward jerks of bill. Male often give short whistle with the display. Given as greeting, threat, and precopulatory display by both males and females.

Bill-jab. Rapid vertical head movements result in head being jabbed straight down. White chin is not exposed. Used frequently at start of courtship sequence; probably functions more in pair formation than in maintenance. Often performed by males in conjunction with Rush (see below) by female. Apparently used by female to signal her mate to defend her.

Rush. Common component of courting groups used by both sexes; suggests more intense level of courtship activity. Begins when individual lowers and extends head, becoming prone in water then dashing with bill open at nearby conspecific. May be used to signal either sexual or aggressive intention.

Inciting. Used by both sexes. Head is lowered over shoulder as quick, pointing movements are directed toward another bird. Used by paired male when approached by unpaired male. Indicates female preference of a mate. Combination of Inciting by female and Turn-the-back-of-the-head Display by male is important to formation and maintenance of pair bonds.

Mutual Preening. Figure 3C . Both sexes often nibble at feathers of mate's head and neck. Bouts may last several seconds to several minutes and function to strengthen pair bond.

Coquette Call. A loud, penetrating terwee given by females. First given in early Aug, especially at nocturnal roost sites; continues through May as part of courtship. Attracts males, reinforces pair bond, and maintains contact during nest search (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Copulation And Copulatory Displays

Copulation takes place on the water and occurs in fall and spring (Figure 3D). Male testes are regressed in fall (Drobney 1977 Drobney, R. D. (1977). The feeding ecology, nutrition, and reproductive bioenergetics of Wood Ducks. Phd Thesis, Univ. of Missouri, Columbia. Close ); copulation at this time probably functions in evaluating potential mates and strengthening pair bonds. Precopulatory displays involve mutual Bill-jerking by males and females, Bathing, and Drinking by males. Copulation begins when female assumes prone position in the water; male mounts from behind, grasps her nape with his bill, and copulates. After dismounting, male swims away a short distance while performing Turning-the-back-of-the-head Display; then faces female as she Bathes. Males also perform Wing-and-tail-Flash, Preen-behind-the-wing, and Bathing after copulating.

Extra-Pair Mating Behavior

Forced copulation by unmated males occurs, but rarely, when mated male is overwhelmed by aggressors. A female drowned in one such attack (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Degree Of Sociality

Generally not in large aggregations except at roosting areas in fall and winter. Typical groups may number 15-50 in late summer and 200-1,000+ at roosting areas. Less gregarious in breeding season than in nonbreeding season. Drobney and Fredrickson (Drobney and Fredrickson 1979 Drobney, R. D. and L. H. Fredrickson. (1979). Food selection by Wood Ducks in relation to breeding status. Journal of Wildlife Management 43:109-120. Close ) reported Wood Ducks feeding in pairs or small groups. Apparently they also migrate in small (6-12 individuals) groups (Grice and Rogers 1965 Grice, D. and J. P. Rogers. (1965). The Wood Duck in Massachusetts. Westboro, MA: Mass. Div. Fish and Game. Close , Kirby et al. 1989 Kirby, R. E., L. M. Cowardin and J. R. Tester. (1989). Premigrational movements and behavior of young Mallards and wood ducks in north-central Minnesota. U.S. Fish Wildl. Serv., Fish Wildl. Res. 5. Close ).

Play

No indication of play.

Nonpredatory Interspecific Interactions

Little information. Wood Ducks often feed and rest with Mallards. Mallards are aggressive toward Wood Ducks where both are attracted to choice feeding areas in flooded bottomlands and waste grain fields (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Kinds Of Predators And Manner Of Predation

A variety of predators documented (see review in Haramis 1990 Haramis, G. M. (1990). "Breeding ecology of the Wood Duck: a review." In Proc. 1988 N. Am. Wood Duck symp., edited by L. H. Frederickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 45-60. St. Louis, MO. Close ). On Eggs. Rat snakes (Elaphe obsoleta; McGilvrey 1968 McGilvrey, F. B. (1968). A guide to Wood Duck production habitat requirements. Washington, D.C: Bur. Sport Fish. Wildl. Close , Strange et al. 1971 Strange, T. H., E. R. Cunningham and J. W. Goertz. (1971). Use of boxes by Wood Ducks in Mississippi. Journal of Wildlife Management 35:786-793. Close , Beshears 1974 Beshears, Jr., W. W. (1974). Wood Ducks in Alabama. Ala. Dept. Conserv. Nat. Resour. Spec. Rep. 4. Close , Hansen and Fredrickson 1990 Hansen, J. L. and L. H. Fredrickson. (1990). "Black rat snake predation on box nesting Wood Ducks." In Proceedings of the 1988 North American Wood Duck Symposium., edited by L. H. Fredrickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 251-254. MO: St. Louis. Close , Hepp and Kennamer 1993 Hepp, G. R. and R. A. Kennamer. (1993). Effects of age and experience on reproductive performance of Wood Ducks. Ecology 74:2027-2036. Close ), raccoons (Procyon lotor; Bellrose et al. 1964 Bellrose, F. C., K. L. Johnson and T. U. Meyers. (1964). Relative value of natural cavities and nesting houses for Wood Ducks. Journal of Wildlife Management 28:661-676. Close , Grice and Rogers 1965 Grice, D. and J. P. Rogers. (1965). The Wood Duck in Massachusetts. Westboro, MA: Mass. Div. Fish and Game. Close , McGilvrey 1968 McGilvrey, F. B. (1968). A guide to Wood Duck production habitat requirements. Washington, D.C: Bur. Sport Fish. Wildl. Close ), fox squirrels (Sciurus niger; Bellrose 1955 Bellrose, F. C. (1955). Housing for Wood Ducks. III. Nat. Hist. Surv. Circ. 45. Close , Bellrose et al. 1964 Bellrose, F. C., K. L. Johnson and T. U. Meyers. (1964). Relative value of natural cavities and nesting houses for Wood Ducks. Journal of Wildlife Management 28:661-676. Close ), mink (Mustela vison; McGilvrey 1968 McGilvrey, F. B. (1968). A guide to Wood Duck production habitat requirements. Washington, D.C: Bur. Sport Fish. Wildl. Close ), various woodpeckers (e.g., Northern Flicker [Colaptes auratus], Red-headed Woodpecker [Melanerpes erythrocephalus], Red-bellied Woodpecker [M. carolinus]; McGilvrey 1968 McGilvrey, F. B. (1968). A guide to Wood Duck production habitat requirements. Washington, D.C: Bur. Sport Fish. Wildl. Close , Strange et al. 1971 Strange, T. H., E. R. Cunningham and J. W. Goertz. (1971). Use of boxes by Wood Ducks in Mississippi. Journal of Wildlife Management 35:786-793. Close , Haramis and Thompson 1985 Haramis, G. M. and D. Q. Thompson. (1985). Density-production characteristics of box-nesting Wood Ducks in a northern greentree impoundment. Journal of Wildlife Management 49:429-436. Close ), and European Starling (Sturnus vulgaris; McGilvrey 1968 McGilvrey, F. B. (1968). A guide to Wood Duck production habitat requirements. Washington, D.C: Bur. Sport Fish. Wildl. Close ).

On Young. Great Horned Owl (Bubo virginianus), mink, snapping turtle (Chelydra serpentina; Ball 1973 Ball, I. J. (1973). Ecology of waterfowl broods in a forested region of north-central Minnesota. Phd Thesis, Univ. of Minnesota, St. Paul. Close , Kirby and Fredrickson 1990 Kirby, R. E. and L. H. Fredrickson. (1990). "Molts and plumages of the Wood Duck." In Proc. 1988 N. Am. Wood Duck symp., edited by L. H. Frederickson, G. V. Burger, S. P. Havera, D. A. Graber, R. E. Kirby and T. S. Taylor, 29-33. St. Louis, MO. Close ), bullfrog (Rana catesbeiana), large predaceous fish (e.g., largemouth bass [Micropterus salmoides], pike [Esox spp.], bowfin [Amia cava], gar [Lepisosteus spp.]), alligator (Alligator mississippiensis). Red-shouldered hawk (Buteo lineatus), Great-blue heron (Ardea herodias), Barred Owl (Strix varia), cottonmouth (Agkistrodon piscivorus; Davis et al. 2009). Before leaving nest, ducklings may be preyed on by egg predators.

On Adults. Great Horned Owl, mink, raccoon, red fox (Vulpes vulpes), gray fox (Urocyon cinereoargenteus), and alligator.

Raccoons are the most important predator of eggs and incubating females over most of the range. In some areas of s. U.S., rat snakes are the most important predator of eggs but seldom kill incubating females (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).

Response To Predators

Where raccoon activity prevails around nest sites, females increasingly flush from nests at the slightest disturbance (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ). Alarm Calls from mother result in ducklings skittering across water to cover while female swims or feigns broken wing in a different direction. Young instinctively dive when cover is unavailable (Bellrose and Holm 1994 Bellrose, F. C. and D. J. Holm. (1994). Ecology and management of the Wood Duck. Harrisburg, PA: Stackpole Books. Close ).