Ducks are often observed swimming on ponds or lakes, which sometimes leads to the assumption that their diet consists mainly of aquatic plants and seeds. Ducks are omnivorous waterfowl, and the answer to whether they consume insects is a definitive “Yes.” Invertebrates represent a substantial and necessary component of their diet. Ducks are opportunistic feeders, and insects and other small aquatic animals are consistently sought after because this animal matter provides concentrated nutrition that supports various biological processes.
Insects as a Key Protein Source
The importance of insects in a duck’s diet is fundamentally a matter of protein, which is difficult to obtain in sufficient quantities from vegetation. Invertebrates are protein-dense, making them especially valuable for ducks during demanding life stages. Growing ducklings, for example, have extremely high protein requirements and may rely on animal matter for up to 90 percent of their diet during their first few weeks of life to fuel rapid growth and development. Egg-laying females also rely heavily on this concentrated energy source during the breeding season to meet the demands of producing eggs. The high-protein invertebrate diet is also necessary during the molting period, as ducks require a massive nutritional input to quickly grow a new set of feathers.
Preferred Prey: Terrestrial and Aquatic Invertebrates
Ducks actively hunt a wide array of invertebrates, with their specific prey determined by whether they are “dabbling” or “diving” species. Dabbling ducks, which feed in shallow water, commonly consume aquatic insect larvae, such as midges, mosquito larvae, and caddisfly larvae, by sifting through the mud and sediment. They also forage on land, targeting terrestrial invertebrates like snails, slugs, earthworms, grasshoppers, and various species of beetles.
Different foraging techniques are used to secure this diverse prey. Dabbling is the most characteristic method, where the duck tips its body forward to submerge its head and neck while its tail remains above the water. This allows them to reach food in water up to 18 inches deep, often employing specialized bill lamellae to strain small food items like planktonic organisms and tiny insects from the water. Diving ducks, in contrast, pursue deeper prey, consuming larger aquatic insects, mollusks, and crustaceans.
Using Ducks for Natural Pest Management
The natural foraging behavior of ducks has been intentionally harnessed by farmers and gardeners as a sustainable method of pest control. Domestic breeds, such as Indian Runner and Khaki Campbell ducks, are particularly effective and are utilized in agricultural settings to manage pest populations without chemical pesticides. This practice is documented in ancient Chinese farming methods, known as “rice-duck farming,” where ducks are released into rice paddies to eat pests and weeds. Ducks are highly efficient at controlling common garden pests like slugs, snails, squash bugs, and ticks, providing effective biological control. Managing the ducks’ access is important, as they are usually introduced after seedlings have matured to ensure they target pests and not the crops themselves.