The Ring-necked Duck (Aythya collaris) is a widespread North American waterfowl species that belongs to the group of diving ducks, also known as pochards. Its diet consists almost entirely of material found beneath the water’s surface in freshwater environments. This species is omnivorous, consuming a variety of aquatic plants and invertebrates, which it accesses primarily through diving. The specific composition of its diet is highly variable and depends on the time of year and the duck’s age.
Core Components of the Ring-necked Duck Diet
The adult Ring-necked Duck consumes a diet that is generally heavier on plant matter, though it is a flexible omnivore. Aquatic vegetation makes up a substantial portion of the food intake for most of the year. This includes the seeds, leaves, tubers, and stems of various submerged and emergent plants.
Common plant foods consist of seeds from species like pondweed (Potamogeton spp.), wild rice, and sedges. Other important vegetation includes the tubers and foliage of hydrilla, coontail, water lilies, and wild celery, all of which are found in shallow wetland bottoms. The duck’s ability to crush hard items like seeds and small shells with its gizzard is a factor in the prominence of plant seeds in its diet.
The animal component of the diet is also important, consisting of a wide array of aquatic invertebrates. These protein-rich items include insect larvae, such as those of chironomids and caddisflies, as well as small crustaceans. Mollusks, particularly small snails and clams, are consistently consumed.
Other invertebrate prey includes freshwater sponges, aquatic earthworms, and leeches. While plant material forms the bulk of the adult diet by volume, animal matter provides necessary protein and nutrients.
Foraging Behavior and Preferred Feeding Environments
The Ring-necked Duck is classified as a diving duck, meaning its primary method of foraging is swimming underwater to seize food items. Unlike dabbling ducks that feed by tipping their bodies on the surface, this species propels itself using its large feet to reach the bottom of the water body. They can also be observed dabbling or collecting items near the surface, but diving is their characteristic feeding behavior.
These ducks prefer shallow, freshwater wetlands for feeding, such as marshes, forested ponds, and bogs. The water depth where they forage is often quite shallow, frequently less than 1.5 meters (about five feet), though they are capable of diving up to 10 meters. A study indicated that they often forage most effectively at depths between 50 and 100 centimeters.
The preferred feeding environments are typically rich in organic material and feature abundant submerged or emergent vegetation. This habitat provides both plant-based food and the dense populations of invertebrates the ducks seek. Soft bottom sediments in these shallow waters make it easier for the ducks to access buried tubers, seeds, and benthic invertebrates.
Diet Adjustments Based on Life Stage and Season
The diet of the Ring-necked Duck undergoes significant shifts based on both its life stage and the time of year, primarily by changing the proportion of plant versus animal matter consumed. Ducklings require a high-protein diet for rapid growth and rely almost exclusively on aquatic invertebrates during their first few weeks of life. For the youngest ducklings, invertebrates can constitute over 70% of their diet by dry weight.
Adult females also drastically increase their intake of invertebrates during the nesting and egg-laying period. This boost in protein is necessary to meet the high energetic demands of egg production and incubation.
Conversely, during migration and the wintering period, the adult diet shifts heavily back toward seeds, tubers, and other plant parts. These plant foods are calorie-dense and provide the necessary energy reserves for long-distance travel and surviving colder temperatures.