Common mergansers can be seen year round in northern New England, but in the spring their numbers peak around the first week in April, due to the large number of birds that wintered further south and are migrating to Canadian nesting grounds. These birds are fish eaters, known to consume at least 50 species which they easily grasp with their bill due to the sharp projections along its edges. Egg-laying is still a couple of months away, but coveted tree cavities where they nest are being scoped out. (female common merganser on left, male on right)
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.