Mallard ducks are a common waterfowl species found across various wetland habitats, including marshes, bogs, lakes, ponds, and rivers. They are also frequently seen in urban settings like city parks, making them a familiar sight.
The Typical Mallard Clutch
A mallard hen typically lays a clutch of 8 to 13 eggs in a single nesting attempt, depositing one per day until the full clutch is complete. Mallard eggs exhibit a range of colors, often appearing creamy, grayish, or greenish buff. While the common range is 8 to 13 eggs, clutch sizes can vary, with nine eggs frequently observed as a typical size.
Factors Affecting Egg Production
The number of eggs a mallard hen produces is influenced by biological and environmental factors. A hen’s age and overall health status play a significant role, with younger ducks sometimes exhibiting lower egg fertility. Adequate food resources and the hen’s nutritional intake are also important determinants of egg production; mallard hens rely on protein-rich wetland invertebrates during the breeding season.
Local climate conditions, particularly temperature, can impact the timing of egg-laying, with nesting sometimes occurring earlier in warmer years. Predation pressure can further affect clutch size; if a nest is destroyed, a hen may attempt to re-nest, though these subsequent clutches often contain fewer eggs. Dense, suitable nesting cover helps mitigate predation risks, contributing to higher nesting success.
Nesting Habits and Incubation
Mallard ducks construct nests on the ground within concealed areas, typically close to a water source. Nests are commonly found amidst dense upland vegetation, beneath overhanging grass, or within shrubs, providing natural camouflage. The hen creates a shallow, bowl-shaped depression, gathering nearby plant materials like grasses and leaves to form the nest.
After laying her full clutch, the hen plucks down feathers from her breast to line and insulate the nest, which also helps conceal the eggs. She does not begin continuous incubation until all eggs have been laid, ensuring ducklings hatch around the same time. The incubation period typically lasts 26 to 30 days, with 28 days being a common average. During this period, the hen remains on the eggs for most of the day, taking brief intervals to feed, drink, and preen, covering the eggs with down when absent.