Pop: Spice cake, Mom — kind of warms one up in this cooler weather. Summer certainly goes by too quickly. I’ll put the kettle on and be prepared for my usual.
Well, we had a pretty lively discussion this morning concerning the article, “The Resurgent Hoods,” by H.W. Heusmann, in the latest edition of the Massachusetts Wildlife magazine. The article is about a small duck that none of us had ever heard of, except Snaid who kept insisting that James Audubon named the species and Mr. Dolan showed him a computer printout that stated that the famous Swedish botanist Carl Linneeus named it in his landmark 1758 10th edition of “Systems Naturae.”
Snaid finally conceded when Mr. Dolan showed him the notation in the MassWildlife article.
The hooded merganser is actually a small duck that nests in tree cavities and dives under water to eat small fish, tadpoles, aquatic insects, crayfish and plant matter. They are about the same size as a wood duck. Length is 15.8 to 19.3 inches, weight is 16 to 31 oz, and wingspan is 23.6 to 26.
Hooded mergansers are short-distance migrants. They are found only in the North America regions where winter temperatures allow ice-free conditions on ponds, lakes and rivers. They have two major year-round ranges. One is in the eastern U.S. from the southern Canada: U.S. border along the Atlantic Coast to the Gulf Coast in the region of the Mississippi Delta. The smaller range is from Washington state and southern British Columbia to northern Idaho. They migrate when necessary to avoid winter conditions that cause water bodies to freeze.
Mom: While the male wood duck is often described as the most beautiful North American duck, the male merganser is quite striking as basically a black and white bird with a fan-shaped crest, which can be raised or lowered. It has a large white patch on the black crest, head black, golden eyes, back and wings of alternating black and white bars, a white belly and golden vermiculated (wavy or winding lines). When the crest is raised, during courting, it covers the entire head (picture it sitting on the head, like a cartoon person whose hair stands up). In comparison, the rusty to grayish brown female is considered drab, but actually quite pretty with a narrow white patch over the lower breast and belly. Her crest is reddish-brown, eyes are brown and back black. Her bill is amber-colored and the male bill is black. Bills are serrated to allow gripping prey.
Hooded mergansers and wood ducks share similar histories of population boom and bust. Extensive forest clearing by early settlers reduced tree nesting sites, Hooded mergansers were common in the mid-1800s, but few by the early 1920s. The Migratory Bird Treaty Act of 1918 helped populations to increase, but along came the Hurricane of 1938 which felled vast swatches of forests containing large trees, and destroyed nesting cavities. Also, hooded mergansers are very susceptible to harm from many types of pollution which reduces populations of prey.
In recent years, proper timber management is increasing available habitat by maintaining a sufficient number of mature trees in which nesting cavities would be plentiful.
In 1943, MassWildlife began erecting wood duck nesting boxes, actually large bird houses. The idea was to attract wood ducks which nest in cavities between rocks or piles of branches. The wood ducks began to use the boxes with so much success that between 1949 and 1953, 3,500 boxes were erected and 4,000 distributed to sportsmen clubs and individuals to place in suitable locations.
Pop: It wasn’t until 1936 that there was a report of a hooded merganser nesting in Groton, and the first report of a hoody using a wood duck nest box was in 1947 in Great Meadows National Wildlife Refuge in Concord. The good news is that the hoodies are starting to use the wood boxes increasingly.
Mergansers form monogamous pairs and remain together until the female has selected a nesting cavity and laid her clutch of seven to 15 eggs. She will not begin incubation until the last egg is laid thereby permitting synchronous hatching (all hatch at the same time). All hatchings are consequently the same size, which facilitates efficient parental care. During incubation, females lose from 8 to 16% of body weight.
Like most waterfowl, hoody hatchlings are precocial, covered with down and able to move about. They usually leave the nest within 24 hours after hatching, and are capable of diving into the water and foraging, but remain with the female for warmth and protection. Incubation period is about 30 days.
Hoodies are difficult to capture and band. If disturbed in the nesting box, it can dive into the water so fast that all one sees is a blur.
Sometimes hoodies eggs and wood duck egg shells are found in the same box, and although there is no evidence of what species the stepmother was, the difference in egg shells allows for the numbers of each. Hoody eggs are rounder than wood duck eggs and have a white porcelain-like finish. Also, the hoody egg shells are twice as thick as a wood duck egg.
The wood duck boxes are also used by other birds for nesting: tree swallows, grackles and the occasional screech owl, plus an assorted species of hornets, bees and wasps.
Kudos to MassWildlife for wood duck boxes.