Texas Waterfowl

Hooded Merganser

120 Goldeneyes, in contrast, have a round to oval white patch in that area. Male Barrow’s Goldeneyes also have a row of oblong white markings along their upper sides. SOURCES Savard 1985; Eadie et al. 2000; Robert et al. 2000; Lockwood and Freeman 2004. HOODED MERGANSER Lophodytes cucullatus Hooded Mergansers have been an unintended beneficiary of nest boxes built for Wood Ducks. They readily use these boxes, and many local populations have been established as a result of nest box programs. Nest boxes have not only played a role in helping this once rare duck rebound, but they have also helped advance our understanding of this species. Females nesting in boxes can be easily monitored compared to those using natural cavities. TEXAS DISTRIBUTION Breeding: Hooded Mergansers are rare, but perhaps increasing, breeders in Texas. Since the late 1970s nesting has been documented in at least eight counties (with evidence for probable breeding in others) spanning the Coastal Prairies, Pineywoods, Post Oak Savannah–Blackland Prairies, and Rolling Plains. Many of these records are related to their use of nest boxes. Migration and Winter: Migrating and wintering Hooded Mergansers are abundant in Texas and potentially occur on wetlands throughout the state, although they are uncommon on playa wetlands. In northern portions of the Rolling Plains and Post Oak Savannah–Blackland Prairies they are most common between mid-November and early March. TEXAS HARVEST From 1999 to 2006, estimated Hooded Merganser harvest in Texas was 5,127 annually . This was about 6 percent of their annual US harvest. POPULATION STATUS Hooded Mergansers have a stable, if not increasing, population. Christmas Bird Counts suggest their wintering numbers increased in 39 of 49 states (excluding Hawaii ) between 1986 and 2006. sea ducks 121 Hooded Merganser (immature male, with black and white plumage visible on the head). Photograph by Mark W. Lockwood, April 4, 2008, Balmorhea State Park, Reeves County, Texas. Hooded Merganser (male). Photograph by Trey Barron, February 15, 2009, Amarillo, Potter County, Texas. 122 DIET Hooded Mergansers primarily forage by diving. Common foods include aquatic insects , crayfish, and fish less than three inches in length. They likely hunt by sight, as they consume brook trout that contrast with the environment more frequently than cryptically colored ones. RANGE AND HABITATS Breeding: Hooded Mergansers breed in forested regions of the eastern United States and southeastern Canada. They also breed in California, the northwestern United States, and western Canada. Breeding pairs are associated with forested riparian areas and forested wetlands. Preformed, existing cavities are required for nesting. Nest cavities may be over land or water. Nest cavity entrances range from 3 feet to more than 88 feet above ground. Migration and Winter: They migrate across much of the United States and Canada. They winter in western Canada, southern Ontario, and the United States. Their distribution is localized in the central United States. They use coastal bays, estuaries, tidal creeks, rivers, forested wetlands, reservoirs, shrub-scrub wetlands, and beaver ponds. REPRODUCTION Pair Bonds: Hooded Mergansers form seasonal pair bonds. Pairs are observed as early as November. Females likely select new mates each year. Males follow their mates to breeding locations. Females regularly use the same nest cavity from one year to the next. Pair bonds dissolve during incubation. Hooded Merganser (female). Photograph by Trey Barron, December 31, 2011, Amarillo, Potter County, Texas. 123 Nesting: Hooded Mergansers nest in natural or man-made cavities. They do not carry vegetation to the nest, but they do add down. Females lay approximately 1 egg every one to two days until the clutch is complete. Clutch size is typically 10–11 eggs. Only females incubate. They spend about 85 percent of their time on the nest. Their incubation period is 29–33 days. Little is known about their propensity to renest if the first clutch is lost, but they will not renest after a clutch hatches. They occasionally parasitize nests of other cavity-nesting ducks. Ducklings: All eggs in a clutch hatch within a span of about four hours. Females fly from the nest and give vocal cues to encourage their ducklings to exit. Females will feign injury to lead predators away from ducklings. Young fledge at roughly 70 days. APPEARANCE Breeding: Hooded Mergansers exhibit strong sexual dimorphism. Males do not acquire their breeding plumage until their second fall or winter. Adult males have a large white crest that is bordered by black.The crest can be raised and...