The mallard (Anas platyrhynchos) is a widely recognized duck species found across temperate and subtropical regions globally. Their adaptability allows them to thrive in various environments, making them a common sight in many landscapes. Understanding where and how these ducks nest provides insight into their widespread presence and successful reproduction.
Preferred Nesting Environments
Mallards exhibit remarkable versatility in their nesting site selection, utilizing a diverse range of habitats. While they prefer ground nests, often concealed under overhanging grass or other vegetation, they can be found nesting in natural wetlands like marshes, swamps, and pond edges. These locations provide close proximity to water, which is important for food sources and for leading ducklings after hatching.
Beyond natural wetlands, mallards also frequently nest in agricultural areas, including fields of alfalfa, winter wheat, barley, flax, and oats. They may even choose roadside ditches for nesting. In more developed regions, mallards have adapted to urban and suburban environments, nesting in city parks, backyards, planters, gravel, and occasionally on rooftops, balconies, or window boxes.
A common requirement across all these varied nesting locations is the presence of dense vegetative cover, which provides essential concealment and protection from predators. Nests are typically constructed in upland areas near water, but can be found up to 2 miles away from wetlands.
Nest Structure and Appearance
A mallard nest is generally a shallow depression, or bowl, scraped into the ground. The female constructs the nest primarily from materials found nearby, such as grasses, reeds, leaves, and twigs. She does not typically carry materials to the nest site, instead pulling accessible vegetation towards her while sitting.
Once egg-laying begins and especially after incubation starts, the female lines the nest with soft down feathers plucked from her own breast. This down provides insulation and helps camouflage the eggs when she leaves the nest. The finished nest is usually about a foot in diameter, with the inner bowl being approximately 6 to 9 inches across and 1 to 6 inches deep.
Mallard eggs are typically creamy white to greenish-buff, or sometimes dull green to almost white, and are usually free of speckles. They measure approximately 2.1 to 2.5 inches in length and 1.5 to 1.8 inches in width. A typical clutch size ranges from 8 to 13 eggs.
Nesting Behavior and Care of Young
Mallards typically begin their nesting season in early spring, with breeding occurring from April to May and extending through early August. The female lays one egg per day, and incubation does not begin until the entire clutch is nearly complete, or all eggs are laid. This synchronized start ensures that all ducklings hatch at approximately the same time, usually within 12 to 24 hours of each other.
The female performs all incubation duties, which last for about 26 to 30 days. During this period, she will leave the nest for short breaks, typically about an hour each morning and afternoon, to feed. When away, she covers the eggs with down and nesting material for warmth and camouflage.
Mallard ducklings are precocial, meaning they are well-developed and active shortly after hatching. They are covered in down and can walk, swim, and find their own food almost immediately. Within 13 to 16 hours of hatching, the ducklings are ready to leave the nest, and the female leads them to a nearby water source. The ducklings remain with their mother for about 50 to 60 days until they are able to fly and become independent.