Red-breasted merganser
The red-breasted merganser is a distinctive species of duck known for its exceptional swimming, diving, and flying abilities, reaching speeds of up to 35 miles per hour (55 kilometers per hour). Males showcase striking plumage with a red breast, dark speckles, a green head, and a double crest, while females are generally brown with grayish underparts. This species, belonging to the genus Mergus within the family Anatidae, typically measures between 20 to 24.5 inches (51 to 62 centimeters) in length and weighs between 28 to 47.5 ounces (800 to 1,350 grams). Red-breasted mergansers primarily feed on fish, utilizing their serrated bills to catch various species depending on their habitat, including salmon and flounder.
During the breeding season, which occurs from April to June, these ducks build nests in dense vegetation or among rocks, laying between 5 to 13 olive-colored eggs. The female incubates the eggs for about 29 to 35 days, and the young are capable of feeding themselves shortly after hatching. Socially, they congregate in flocks, particularly during winter months, where they can number from 20 to over 1,000 members. The life expectancy of red-breasted mergansers is approximately nine years, and they exhibit relatively quiet behavior, with females occasionally emitting rasping calls during the breeding season.
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Red-breasted merganser
This duck is known as an excellent swimmer, diver, and flyer. It can fly at 35 miles (55 kilometers) per hour, making it one of the fastest ducks in the world. Other names for these ducks include spring sheldrakes, sea robins, popping wigeons, earl ducks, and bedrakes.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Mergus
Species: Serrator
As the name suggests, the breast of the male red-breasted merganser is red with dark speckles. The rest of his body is gray with white sides and a black back. A white ring around his collar contrasts his bright green head. Long, fine, feathers form a double crest on the back of his head. The female also has a double crest on her brown head. Her throat and underparts are grayish white, and the rest of her body is gray. Males and females have long, red, flat bills with serrated, or jagged, edges. These edges look like the teeth of saws. These ducks are grouped with ducks with similar bills called sawbills. Red-breasted mergansers are 20 to 24 1/2 inches (51 to 62 centimeters) long and weigh 28 to 47 1/2 ounces (800 to 1,350 grams). Their wingspans may reach 27 1/2 to 34 inches (70 to 86 centimeters).
Small groups of red-breasted mergansers use their superb swimming and diving skills to catch fish. In freshwater, they eat salmon, pike, stickleback, insects, crustaceans, amphibians, and eels. In saltwater, they eat flounder, herring, gobies, and sand eels. When fish are not within reach of their saw-toothed bills, the ducks may seize crabs, shrimp, the larvae of aquatic insects, and the roots, leaves, and seeds of aquatic plants. Feeding dives may last up to two minutes but average 30 seconds. Several mergansers may form a line and move across the water to corral the fish into shallow water where they are easier to catch.
Winter flocks usually have 20 to 30 members but may have 1,000. During these months, they feed in shallow, sheltered inlets, estuaries, and bays with banks for roosting sites. Large summer flocks of red-breasted mergansers may breed in coastal waters near forests and swampy tundra or may move to inland lakes and rivers with similar surroundings.
Mergansers choose one mate for a single breeding season. From April to June, they mate, building nests alone or in colonies. The nest site is often amid dense vegetation where grass, heather, or brambles cover the nest. The path to the nest is often a tunnel through vegetation. Other nest sites may be among boulders, tree roots, or old rabbit burrows. The female lays 5 to 13 olive eggs and incubates them for 29 to 35 days. The young can feed themselves shortly after hatching and can fly after 60 to 65 days. Broods, or groups, of young often form small flocks when their mothers leave them at about two months of age. The end of the summer breeding season results in the migration of duck colonies to coastal areas for winter. The young mergansers can mate after two years.
Red-breasted mergansers do not make much noise. Females make rasping calls during the breeding season, and the males answer with calls that sound like a cat.
The life span of red-breasted mergansers is around 9 years.
Bibliography
"Red-breasted Merganser." National Audubon Society, www.audubon.org/field-guide/bird/red-breasted-merganser. Accessed 15 Apr. 2024.
"Red-breasted Merganser." The Wildlife Trusts, www.wildlifetrusts.org/wildlife-explorer/birds/waterfowl/red-breasted-merganser. Accessed 15 Apr. 2024.