Diving ducks earn their name from their hunting behavior. Depending on the species, these ducks can dive up to ten or more feet below the water in search of food. And they can hold their breath for a minute or longer. These ducks have heavy bodies, broad webbed feet and compact, small wings that allow them to quickly propel themselves underwater to search for food. Diving ducks spend most of their time hunting far off the shoreline in the deep waters of bays and estuaries. During their dives they hunt for fish, mollusks, crustaceans, invertebrates, insects and occasionally feed on aquatic plants. The diving duck prefers to eat animals more than vegetation.
Diving ducks spend the majority of their lives in the water because their body structure makes it difficult for them to walk and fly. Unlike their relatives the puddle ducks, diving duck’s feet are wide apart and toward the very back of their bodies. This causes them to have difficulty balancing on land. Their small wings force them to begin their flight by running on top of the water to build up momentum.
During breeding season, male ducks (drakes) chase the female ducks (hens) to mate. The drake will use stylish movements and calls to impress her because in the end it is the hen that chooses the male. If the drake is successful, the pair will start a family together. The female will begin building a nest out of vegetation which she will place within the crevice of rocks or the cavity of a tree near the shoreline. Once the female lays the eggs, the male will return to a group of all males that will travel elsewhere to mate again. The female will incubate the eggs. From the moment the ducklings hatch they are self-sufficient, already knowing how to feed themselves and swim. Their yellow and brown coloring helps protect these ducklings from predators before they learn to fly. Predators include raccoons, coyotes, minks, hawks and owls. Other species like skunks, crows and turtles have scouted out these ducks since they were an egg. After only two months the ducklings develop the skill to fly.
During the post-breeding months diving ducks generally hide in broad waters. Drakes, who wear a few stripes of bright color or patterns during the breeding months, molt into a dull brown or gray coloring. This occurs because their striking coloring is no longer needed to attract the attention of a mate. During this molting period the males are unable to fly due to losing feathers. Once their new plumage grows in many migrate south for the warm weather. Females never change their coloring, staying a brown dull color to camouflage themselves while nesting.
Several types of diving ducks have faced a decline in population due to natural and human causes. Farming has played a large role in the decrease of diving ducks due to draining habitats for agricultural use. Storms also threaten diving ducks. Excess water and icy roads can cause ducks to believe they’re seeing a pond. After landing on a road, the ducks are unable to build the momentum to fly, which can lead to their death.
The Virginia Living Museum exhibits three types of diving ducks: the canvasback, the hooded merganser and the double-crested cormorant.
The canvasback diving duck (Aythya valisineria) gets its scientific name from the celery plant. The word “valisineria” is the taxonomy name for wild celery and the canvasback’s favorite food. The canvasback is a large duck almost 20 inches long and weighing 2.5 to 2.75 pounds. With the exception of its chest, which is colored black, the canvasback wears a full white coat of feathers. Female canvasbacks have a brown colored head while the males are slightly more colorful with a red colored head. This large bird has the ability to fly up to 70 miles per hour and typically travels with a flock of ten to 30 birds. The flock can be spotted flying along the coast in the shape of a ‘V”.
Canvasbacks are mainly plant eaters, but they will occasionally add sea creatures. The majority of their diet consists of leaves, roots and the seeds of pondweeds, sedges and grasses, along with mollusks, insects, crustaceans and small fish.
Breeding season begins in March and April. Drakes will begin attracting mates by shaking their heads back and forth and making cooing and clicking noises in front of the females. Nests are made of plants, sticks and leaves and are usually placed in tree cavities of swamps. A female canvasback can lay ten to 12 eggs per nest.
After breeding season many canvasbacks will head south. Nearly half of the North American canvasback population will migrate to the Chesapeake Bay.
Merganser diving ducks are also known as “fish ducks” or “sawbills.” These nicknames come from the duck’s typical diet of fish, as well as from the sharp and jagged bumps on their bills. This characteristic helps mergansers keep hold of fish while they hunt. There are three types of mergansers in North America – the hooded merganser, the common merganser and the red-breasted merganser. The Virginia Living Museum currently has the hooded merganser on exhibit.
The hooded merganser has a colorful plumage, weighs about a pound and a half, and is 16 to 18 inches long. The hooded merganser can fly very fast and low to the water, allowing it to catch much of its prey. It eats mainly aquatic animals such as fish and fish eggs more than vegetation. Hooded mergansers prefer forested wetland systems, where they nest in tree cavities or nest boxes and lay an average of nine to 11 eggs.
The double-crested cormorant has a dull black coloring with an orange and gray bill. Though cormorants constantly dive in the water for food their wings are not as waterproof as other diving ducks. They are usually found standing on rocks or branches with their wings stretched to dry after performing a dive. Their diet includes fish, eels, crayfish, frogs, salamanders and snakes. Double-crested cormorants hunt both in groups and alone.
They nest in colonies among other fishing birds like herons. Nests are built out of sticks and vegetation and are usually placed within the branches of trees. During breeding season the nests will hold three to four pale blue eggs. Unlike other diving ducks, both the male and female will incubate the eggs. The eggs hatch after a month and the young stay in the nest for about four weeks. During these first few weeks the ducklings are able to fly (however they do not venture far from the colony).
Double-crested cormorants breed in the West and upper Midwest of the United States, as well as along the Atlantic coast of North Carolina and further south. It is rare to spot a double-crested cormorant breeding in Virginia.