The Mallard is an ancestor to most domestic ducks, excluding the Muscovy, which makes it the most abundant and widespread of all duck breeds.
Mallards are large ducks that grow to about 24 inches and about 3-4 pounds. In the winter, adult males (drakes) are commonly called “green heads” because of their iridescent, glossy green head that may appear black or purple in certain lighting.
Drakes have a white collar around their necks and dark curly feathers at the base of their tails that are called drake feathers. Both drakes and hens have a speculum, which is a purplish-blue patch of feathers bordered in white on their wings. This distinctive trait helps distinguish the females from other similar ducks, though it is not always visible.
Mallards were once known as “Wild Ducks” in England and some people still refer to the plain brownish hens as “Susies.”
The word “Mallard” is Old French for “wild drake.” The scientific name is derived from the Latin “Anas” for “duck” and the specific name “platyrynchos” comes from the Greek phrase “broad beak.” This name was created by Carl Linnaeus himself.
Mallards are the largest dabbling, or puddle, ducks. They normally feed at the surface, tipping their bottoms-up to reach food below. They rarely dive under water unless they are wounded or in need of an escape.
While most diving ducks need to patter or run along the surface before attaining flight, dabblers spring directly into the air for take off.
Mallards consume plant material throughout most of the year. Up to 90% of their diet consists of aquatic plants, seeds, tubers, and grains.
Large flocks may descend into fields for corn stubble and soy, or furiously feed on water fleas and fingernail clams in small vernal pools.
Occasionally, 70% or more of their diet switches to animal matter. This is particularly true of hens prior to nesting when they need all the protein and calcium they can find. Hens may hunt wood frogs and swallow them whole. In their growing stages, ducklings feed heavily on insects and small invertebrates before switching to a mostly vegetarian diet.
When it comes to matting, hens always seem to be in short supply. Mallard drakes attempt to display and pair themselves with hens from winter into early spring. They become noticeably aggressive with their pursuit in late spring. Any single hen, whether she be abandoned or poorly defended by her mate, can be pursued by other males. A group of males may even aggressively gang up on the single hen, which has caused injury and death to single hens. This is exasperated in overcrowded situations.
This aggressive urge for mallard drakes to mate is not limited to Mallards. Hybrids are not uncommon, and sometimes result from forced copulation. In short supply of hens, domestic mallards have attempted to mate with chickens, but instead drowned them in their pursuit.
Mallard males’ broad acceptance for mates results in hybrid duck species, including mixes of Mallards and Pintails, Gadwalls (what Audubon called a Brewer’s Duck), Widgeon (both American and Eurasian), Shovelers, Green-winged Teal, Cinnamon Teal, Eurasian Teal, and other domestic ducks.
In some parts of the world, Mallards are considered invasive, threatening to out-breed local species. This is the case with Africa’s Yellow-billed and Meller’s Ducks, Pacific Black Ducks, and Asian Spot-billed Ducks.
Mallards are the most adaptable of ducks, perhaps due to their escape and release from captivity, and have moved into habitats that once belonged to other duck species. They aren’t picky about nesting locations and often benefit from a close proximity to people.
It is illegal in some areas to release or keep Mallards because feral ducks, or those fed by people, may not migrate, a trait that may carry on through mating. Mallards have the most extensive breeding range of any North American duck and will nest the first year after being born. They have been expanding their breeding range since the early 1900’s, perhaps at the expense of other duck types.
Once a Mallard hen has mated, she chooses a nesting site which is usually near water, or up to one mile away. Hens across many duck species sometimes dump their eggs into other ducks’ nest or have another duck’s eggs dumped into theirs. Hens sometimes choose unsuitable sites which is the case in the videos of people rescuing ducklings from roofs, garages, and helping them cross busy streets. Males do not help raise the young; they form small bachelor flocks during the warmer months.
If nesting goes smoothly, then each hen lays about an egg a day in her ground nest until she reaches her compliment of 8-12 eggs. The eggs can make up more than half a hen’s weight, which is taxing on the mother. Hens will often sit tight concealing their nests no matter what danger approaches them. Some farmers use “flushing bars” ahead of their mowers and tractors to spook the hens into moving. A hen and her eggs is often preyed upon or caught by predators such as foxes, coyotes, skunks, raccoons, possums.
Ideally, a hen will incubate her greenish-white eggs for about 28 days before they all hatch. Within hours she leads her precocial ducklings to water. About sixty days later they are fledged. If successful, hens often return to nest near where they nested the previous year.
Mallards are very vocal and gregarious ducks. Hens quack loudly and often while drakes quack infrequently and quietly. Mallards are the most hunted of all ducks because they respond well to calls, decoys and are considered decent table fare. Their numbers fluctuate yearly, but are considered stable. Duck population and nesting surveys are often based heavily on Mallard numbers before setting hunting seasons and limits.
Mallards are common because they are adaptable. They will winter as far north as the food supply and open water allows, sometimes paddling around in small flocks to keep an opening in the ice.
Mallards are abundant and adaptable survivors. Healthy Mallards are known to live as long as 26 years and 4 months (as we have learned from recovered banded waterfowl). They are quite beautiful ducks that are accustomed to and appreciative of humans, just like humans are of them.