Hooded Merganser

Lophodytes cucullatus

(c) Jim Fenton
  • ANATIDAE
  • Swans, Geese, Ducks
  • Anseriformes
  • Serreta capuchona
  • Harle couronné
Introduction
The Hooded Merganser is one of North America's handsomest, though least numerous, ducks. This secretive species prefers wooded ponds, lakes, and streams, where it often goes undetected. Due to its retiring nature, exact population estimates are difficult to obtain.
(c) Glen Tepke
Appearance Description
The male Hooded Merganser, with his brown sides, black head and back, and white breast and belly, is unmistakable among North American waterfowl. His most distinguishing feature is his crest, or “hood.” At rest or in flight, this hood appears as little more than a white line behind the eye, but when the drake is alert on the water, the fully-raised crest reveals an elaborate hood of white on an otherwise black head. Unlike other mergansers, which sport red bills, the bill of the drake Hooded Merganser is black. As with most duck species, the female is far more understated. She is small and grayish-brown overall, with a shaggy, cinnamon-colored crest at the back of the head.
Range Map
Courtesy Kenn Kaufman
Range Distribution
Hooded Mergansers are found in the forested areas of eastern North America, with the densest concentrations around the Great Lakes. Another population breeds in the forested Pacific Northwest. In between, they occur mainly as migrants, if at all. This merganser is the only member of its genus to occur exclusively in North America.
 
A legend for the range map to the right can be found here.
Habitat
This secretive duck prefers quiet, out-of-the-way wooded ponds, lakes, streams, and swamps. In migration, they prefer similar habitat, but make use of a wider variety of areas with open fresh water. The presence of mature, cavity-bearing trees is essential for nesting, although Hooded Mergansers occasionally make use of nest boxes placed in less typical habitat. These mergansers are known for choosing hidden wet areas, where they can be extremely difficult to detect, even by experienced bird watchers and researchers.
Feeding
Like other mergansers, Hooded Mergansers dive for their food. They are strong underwater swimmers, with eyes specially adapted for foraging amidst the murky bottoms of lakes and ponds. Unlike other mergansers, which prefer fish, a large portion of the Hooded Merganser’s diet is made up of insects and crustaceans, particularly crayfish. Small fish and a limited amount of vegetation are also eaten.  
Reproduction
Pairs form over the fall and winter. In spring, the female merganser chooses a suitable nest cavity, where she lays her clutch of eggs. The nest cavity is near water, and typically 10 to 50 feet above the ground. Once the cavity is chosen, available materials may be moved around a bit, but only downy feathers are added. Males disappear shortly after the nest site is chosen; females are responsible for incubating and rearing the young. When her ducklings are only a day old, the female flies to the ground and calls to them until they climb out, one by one, and leap to the ground. At this point she leads them to water, where they are immediately able to feed themselves, swim, and even dive. A curious aspect of breeding among Hooded Mergansers is nest parasitism, or the laying of eggs in other birds’ nests. Hooded Mergansers are both the perpetrators and victims of this practice; in extreme cases, females have been found attempting to incubate as many as 40 eggs, a fraction of which are actually her own.
Migration
Depending on where they breed, most populations of Hooded Mergansers are short- to medium- distance migrants. This hardy species often winters as far north as open fresh water can be found. In spring, they may arrive on breeding grounds within days of the local ice melt.
CBC Graph
Graph Legend
Annual Population Indices
  • 350,000
  • 350,000
  • small population size, small wintering range
Population Status Trends
Although precise trends are difficult to pin down for this secretive species, Hooded Mergansers probably bred widely across eastern North America in pre-colonial times. Their numbers had declined drastically by John James Audubon’s day, as North America’s forests were cleared. The population hit historic lows during the mid-1900s, but is now thought to be rebounding in many areas, thanks in part to modern forest conservation programs. Presently, numbers are thought to be stable, if not increasing slightly. Estimates vary, but the current population of about 350,000 individuals makes the Hooded Merganser one of North America’s least numerous ducks.  
 
An explanation of the Annual Population Indices graph displayed to the right can be found here.
Conservation Issues
Today, the major threat to Hooded Mergansers is habitat loss. Responsible management of North America’s forests is imperative, as Hooded Mergansers rely on the presence of large, cavity-bearing trees for nest sites. Over-hunting presents another challenge. Even though they are not popular game birds, an estimated 80,000 Hooded Mergansers—up to 26% of the global population—are killed by hunters in the United States and Canada each year. Continued monitoring of bag limits and seasonal restrictions is crucial. Hooded Mergansers also make ready use of human-made nest boxes, often nesting in structures intended for Wood Ducks.
What You Can Do
Provide Hooded Merganser nest boxes in appropriate habitats. For plans and placement tips, visit the Cornell Lab of Ornithology’s Birdhouse Network website: http://www.birds.cornell.edu/birdhouse/resources/
 
Remain aware of local, regional, and federal land management decisions, particularly those that affect our forests and wetlands.
 
Contact your legislators in support of wise land management initiatives, such as wetland restoration, and The North American Waterfowl Management Plan.
 
For actions you can take, including Audubon activities, please visit our resources page.
More Information
 Ducks Unlimited maintains important information on many issues affecting North American waterfowl: http://www.ducks.org/conservation/index.asp
 
Visit our resources page for more information about this species.
Natural History References
Bent, Arthur Cleveland. 1962. Life Histories of North American Wild Fowl: Part One. Dover Publications, Inc., New York.
 
Dugger, B. D., K. M. Dugger, and L. H. Fredrickson. 1994. Hooded Merganser (Lophodytes cucullatus). In The Birds of North America, No. 98 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists’ Union.
 
Kaufman, Kenn. 1996. Lives of North American Birds. Houghton Mifflin Company, New York.
 
Kortright, Francis H. 1943. The Ducks, Geese and Swans of North America. The American Wildlife Institute, Washington D.C.
Conservation Status References
Dugger, B. D., K. M. Dugger, and L. H. Fredrickson. 1994. Hooded Merganser (Lophodytes cucullatus). In The Birds of North America, No. 98 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists’ Union.
 
Kaufman, Kenn. 1996. Lives of North American Birds. Houghton Mifflin Company, New York.
 
Kortright, Francis H. 1943. The Ducks, Geese and Swans of North America. The American Wildlife Institute, Washington D.C.