When Dave and I went to Cape May in December, we saw a variety of waterfowl. Even with our binoculars, some of the birds were really far out so a few were hard to see. I was at home reviewing the pictures, and zoomed in on a picture of Bufflehead. But as I looked closer I realized “wait…those aren’t Bufflehead, they’re Hooded Mergansers!” . They blended in so well that I didn’t even realize I saw them on the trip until I got home. It’s always fun to find a little surprise like that, so today I’m featuring them as this week’s waterfowl.
Today’s post is dedicated to my mom because she suggested I write about mergansers (and we happen to have an inside joke about them lol).
Hooded Merganser (Lophodytes cucullatus)
Hooded Mergansers are the smallest of the 3 North American merganser species. ” Hoodies” have longs bodies, slender bills, and round tails. They are sexually dimorphic, so males and females have distinct plumage. Males have chestnut flanks, white underparts, and black upperparts. The males have a large, prominent white patch on the head that varies in size when its crest is raised or lowered. Females and juveniles are a dull gray-brown with a cinnamon-colored crest. Juveniles differ from females because or their dark bills (as opposed to the female’s yellow) and yellow eyes (female’s eyes are dark).
Year-round: Northwest and Eastern United States Summers (breeding): Central to Eastern Canada; Great Lakes region of the United States Winter: parts of the Western United States, parts of the Southeast, and Florida
Open water; wooded ponds, tidal creeks, marshes, swamps
Fish, aquatic insects, vegetation, crustaceans, amphibians, and mollusks. Hoodies have a broader diet than other mergansers, who mainly eat fish. They dive underwater to find prey, which they catch by sight. The have nictitating membrance (a.k.a “third eyelid”) that protects their eyes while they hunt underwater.
Hoodies court in large groups that typically consist of one female and many males. Male will put on a elaborate “head-throwing” display, where they toss their heads back with their crest raise while croaking. Females respond with head bobbing and a hoarse gack croak. Hooded Mergansers nest in tree cavities that the females line with down.They may also use nest boxes. Once the females lays her 10-12 eggs the male abandons her. It’s not known if pairs reunite the following year.
A female will incubate her eggs for 26-41 days, but typically around 33. It’s common for a female to lay some of her eggs in another merganser’s nest, which is an example of brood parasitism. The ducklings will leave the nest within 24 hours after hatching. They are called by the female from below the tree and the duckling will “sky-dive” down to her. The chicks are able to dive shallowly and feed themselves, but the female will tend to them for several weeks. The ducklings fledge about 70 days after leaving the nest.
Usually silent, except for during courtship. Males have a purr-like croak, sometimes being nicknames the “frog duck”. Females give a gack during courtship and sometimes a soft wrrep. In flight or when calling her chicks the female will use croo-croo-crook
It’s thought that Hoodies have the smallest number of the 3 North American mergansers. Numbers have declined over the decades due to habitat loss. However, the population has slowly increasing, partly due to artifical nest boxes that are meant for Wood Ducks.
- The female begins incubating her eggs after the last one is laid, therefore allowing for synchronous hatching.
- Hoodies are the second smallest merganser of the 6 merganser species in the world. The smallest is the Smew.
- To protect the eggs or chicks, a female may use the “broken-wing” display to distract predators (similiar to the Killdeer).
- Females only lay up to 13 eggs per brood, but due to brood parsitism (females laying eggs in each other’s nests), there have been nests found with up to 44 eggs in them!