Hooded Merganser are the smallest of the three North American mergansers. As secondary cavity nesters, they are dependent upon old growth forested wetlands, although their tendency to nest in artificial nest houses has expanded the types of habitats they will occupy.
DISTRIBUTION: Oberholser (1974) describes the occurrence of the Hooded Merganser in Texas primarily as a winter migrant present from November to March, but does list two spring sightings, one summer sighting, and one summer specimen record. Its distribution was thought to be irregularly common to rare and local throughout, but most numerous in the northern third of the state. Bellrose (1976) and Dugger et al. (1994) report no nesting records from Texas.
However, the TBBA data indicate Hooded Mergansers do breed in Texas. There were three confirmed sightings of fledglings in 1987. In 1988, two sightings of possible breeding adults were reported, and one probable sighting in 1989. Further, field observations from 1994 confirm nesting attempts by Hooded Mergansers east of Gilmer, Texas in Upshur County as well as visual observations of an adult in flight during April 1994 in northwest Angelina County.
SEASONAL OCCURRENCE: The Hooded Merganser is difficult to confirm as a breeding bird in Texas. It is secretive and inhabits habitat that is difficult to survey. The existing sightings suggest that it occurs as a breeding bird in east Texas from Lufkin to Gilmer and west to Henderson and Navarro counties. The majority of the nesting activity takes place between February and April (Bellrose 1976). Clutch size ranges between 7 to 13 eggs with an average of 10.6 (Bellrose 1976). Morse et al. (1969) considered clutch size might vary with age; first time nesters laid an average of 9.6 eggs compared to 10.8 for hens that had nested previously.
BREEDING HABITAT: Hooded Mergansers generally prefer the same habitats as Wood Ducks (Aix sponsa), and nesting Hooded Mergansers are often discovered during routine nest box surveys for Wood Ducks. Field research in 1994 documented hatching of mixed clutch of Hooded Mergansers and Wood Ducks. Natural habitat in Texas is probably bottomland hardwood wetlands (DR, 1994 observations), consisting of mature oaks (Quercus spp.) capable of producing natural cavities, with an understory of water elm (Planera aquatica), button-bush (Cephalanthus occidentalis), and wax myrtle (Myrica cerifera). Wooded creeks and beaver ponds are probably important habitats as well.
STATUS: It is likely that Hooded Mergansers have been nesting in Texas for some time, but have simply gone unnoticed. The bird is a secretive species, even more intolerant of disturbance and activity than the Wood Duck. Observations of nesting birds in Texas are increasing, especially in suitable habitat where nest box management for Wood Ducks is in place.
Text by Dean Ransom (Posted 2006)
Literature cited.
Bellrose, F. C. 1976. Ducks, geese and swans of North America, 2nd ed. Stackpole Books, Harrisburg, PA.
Dugger, B. D., K. M. Dugger and L. H. Fredrickson. 1994. Hoodded Merganser (Lophodytes cucullatus). InThe birds of North America, No. 98 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
Morse, T. E., J. L. Jakabosky and V. P. McCrow. 1969. Some aspects of the breeding biology of the Hooded Merganser. J. Wildl. Manage. 33: 596-604.