Wood Duck Aix sponsa Linnaeus       Field Guide IDs: NG-74; G-52; P-50; PW-pl 13; AE-pl 119; AW-pl 114; AM (I)- 152 Nest Location Nest Type Eggs & Mating System Dev. & Parental Care Primary & 2ndary Diet.. Foraging Strategy F I: 28-37 DAYS PRECOCIAL 2 > 30 feet NESTBOX 2 feet - 65 feet F 10-15 (6-15) MONOG F: 56-70 DAYS F SEEDS BREEDING: Wooded swamp, bottomland slough, flooded forest, pond, marsh. 1 brood, occ 2, esp in s. DISPLAYS: Courtship and pair formation begin in autumn, continue into spring. Courtship bouts in groups avg 11 birds, males outnumbering females; always includes vocalizations. See: Duck Displays. NEST: Prefer tree cavity. Lined with wood chips, down. Occ use abandoned nest hole of other species, rock fissure. Perennial. EGGS: Creamy white. 2.0" (51 mm). DIET: Seeds, acorns, berries, grain; aquatic and terrestrial insects, other invertebrates. CONSERVATION: Winters s to Cuba and Bahamas. Market-hunted for plumage, food, and eggs; nest habitat lost through development and forestry practices; by early 1900s verged on extinction, but made comeback. Readily use nest boxes. NOTES: Older males pair earlier in season than yearlings. Females show extremely strong nest site tenacity. Clutches of 15-50 result from 2-10 + females contributing to individual nests ("dumped"); dumping increases with increased density of nest boxes. Female will repel parasitizing females from her nest. Young remain in nest 24 hours; sharp-clawed, can climb up to 8' out of cavity. If disturbed, young submerge like grebe or dive to reach cover. STANFORD. NOTES: ESSAYS: Site Tenacity; Plume Trade; Parasitized Ducks. REFERENCES: Armbruster, 1982; Bellrose, 1976; Drobney and Fredrickson, 1979; Gooders and Boyer, 1986; Semel and Sherman, 1986.