Immature Common Merganser Diet
Common Mergansers are primarily fish-eating ducks. Young mergansers require over half a pound of food per day during their first summer, and often supplement their fish diet with insects, mollusks, crustaceans, worms, frogs, small mammals, birds and plants. The pictured immature Common Merganser had just downed a crayfish when it spotted a frog which it succeeded in catching and eventually swallowing.
Ring-necked Ducks
Although named for the chestnut band, or ring, around its neck (barely discernible to most eyes) this diving duck does have a distinct white ring around its bill. Vermont and New Hampshire are on the southern edge of the ring-necked duck’s breeding range, so while they do breed here occasionally, we’re much more apt to see them during March and April, when they are migrating further north, and again in October and November when they’re headed to southern U.S. and central America to spend the winter. (male on left, female on right in photograph)
Hooded Mergansers
A few hooded mergansers, small fish-,insect- and crayfish-eating ducks of wooded ponds, can be found year round in northern New England, but their numbers swell in March and April, when many migrant birds return to breed, and others stop over on their way further north. Standing dead trees, or snags, provide nesting cavities for these beautiful, “hammerhead” crested ducks. (Male hooded merganser on left and female on right in photograph.)
Redhead
As dusk approached, a Redhead (Aythya americana) drake repeatedly disappeared under water, coming up with a mouthful of aquatic vegetation each time it dove. Suddenly an agitated Crow started cawing nonstop. Soon thereafter a Bald Eagle soared overhead, scanning the open water for its next meal. The Redhead immediately dove, and wasn’t seen again for several minutes. Knowing it couldn’t hold its breath for that period of time, I began looking more carefully for where it had surfaced. Eventually I found it seeking shelter from above, tucked under a snag which had fallen into the pond.
Naturally Curious with Mary Holland 
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