Ducks are highly adaptable birds that forage opportunistically for a wide range of foods. Their feeding habits allow them to thrive in various environments, from wetlands to agricultural fields, consuming whatever is most readily available. This flexible approach to diet means they can adjust their foraging based on season and habitat, utilizing diverse food sources as they become abundant.
Acorns as a Duck Food Source
Ducks consume acorns, particularly during autumn and winter when these nuts are plentiful. Acorns are a significant food source for certain duck species, especially dabbling ducks like mallards and wood ducks. These birds actively seek out acorns in flooded bottomland forests and along shorelines where oak trees are present.
Ducks typically access acorns by foraging in shallow water or on land, using their specialized bills to scoop up the nuts. While some acorns may be too large to swallow whole, ducks, particularly wood ducks and mallards, can consume surprisingly large ones, sometimes working them down with head movements. Acorns from red oak species, such as willow, water, cherrybark, and pin oaks, are commonly eaten.
Nutritional Role of Acorns in Duck Diet
Acorns offer a dense source of energy for ducks, contributing significantly to their dietary needs during colder seasons and periods of high energy demand. They contain carbohydrates and fats, providing fuel for activities like migration, breeding, and maintaining body temperature. Acorns have a high calorie density, with dried acorns containing approximately 144 calories per ounce, and raw acorns about 110 calories per ounce.
Comprised of about 41% carbohydrates, 53% fat, and 6% protein, acorns are valuable for building fat reserves in migrating and breeding ducks. While acorns also contain some protein, various vitamins, and minerals, their primary contribution is their high energy content. Red oak acorns, despite having more tannins, have higher fat, protein, and calorie content compared to white oak acorns.
Broader Duck Diet and Foraging Habits
Ducks are omnivorous, consuming a wide array of plant and animal matter. Their diet varies greatly depending on species, habitat, and time of year. Beyond acorns, common food sources include aquatic vegetation, seeds, grains, insects, larvae, small fish, and crustaceans.
Dabbling ducks, for instance, often feed on aquatic plants such as wild rice, wild celery, coontail, and pondweed, as well as their seeds. They also forage for invertebrates such as water beetles, dragonfly nymphs, and mosquito larvae, which provide essential protein. Ducks use various foraging techniques, including dabbling—tipping forward to reach submerged food—and grazing on land. The ability to consume a diverse range of foods allows ducks to adapt to changing food availability across different seasons and environments.