About The Hooded Merganser

The Hooded Merganser is the second smallest (16-19 inches long) of the six living species of mergansers and the only one whose range is restricted to North America. Like all mergansers, it has a long, serrated bill tipped with a hooked nail. The adult male has white fluffy, fun-shaped crest on its head. It has bright gold eyes, black head, brownish-black back, rusty sides and white chest bordered by black and white stripes. The adult female is brownish overall with blackish green upper mandible and yellowish lower mandible.

The Hooded Merganser Nesting Preferences

The female Hooded Merganser chooses the nest site usually in a tree or nest box 10 to 15 feet above the ground. The nest is made from materials found in the cavity. The female finishes off the nest by plucking down from the patch in her belly. Between 10 to 12 spherical and thick-shelled eggs are laid. The female alone incubates the eggs for nearly a month during which time she loses 8-16% of her body weight. The male abandons the nest shortly after incubation starts. After the eggs hatch within 24 hours, the ducklings jump to the ground and head for the water. The female tends to the young and leaves them at 10 weeks of age.

Building a Birdhouse For The Hooded Merganser

Small, forested wetlands including beaver ponds, swamps and river edges are the preferred habitats of Hooded Mergansers. They have been known to use man-made nesting boxes in more open habitats. The interior of an ideal birdhouse for a bird this size has a 12 inches x 12 inches floor and 24 inches inside ceiling. The entrance hole is 3 inches high x 4 inches wide horizontal oval located 21 inches above the floor. Line the floor with 3-4 inches of woodchips. Place the birdhouse 10 feet or higher on a tree trunk or 6-8 feet if on a post in water. The birdhouse may also be placed in wetland edges within 100 feet of a river or pond to allow the ducklings to trek on water.

The Hooded Merganser Mating Habits

Male courtship involves fancy displays of his crest and unique vocalizations. The male throws back his head sharply until it touches his back; then bring it back forward slowly while giving off a frog-like croak. Other displays may include wing flapping and stretching or shaking. The female may pump her head in response to the male’s display. She then stretches her neck and head out just above the water and lays her tail flat on the water surface to entice the male. Mating then occurs on the water.

The Hooded Merganser Feeding Preferences

Hooded Mergansers track down their prey visually, diving and foraging on lake, river or pond bottoms for fish, crayfish, clams, crabs and other crustaceans. They have strong muscular gizzards that help them grind down the skeletons of shellfishes. They also eat aquatic insects and aquatic plants.

Interesting Hooded Merganser Facts

Hooded Mergansers have a relatively small population due to delayed breeding which occurs only until age two. They form groups of no more than 10 or 12. They can fly at speeds approaching 50 miles per hour. Female Hooded Mergansers do not lay more than 13 eggs. They catch fishes by direct underwater pursuit remaining submerged for up to two minutes. They can change the refractive properties of their eyes to enable them to see more clearly underwater.