Ducks are omnivorous birds that will eat a wide variety of foods, and a varied diet provides good nutrition for healthy duckling growth, feather strength, muscle development, breeding success and more. Understanding what ducks eat can help birders provide a suitable diet for any ducks that frequent their local ponds or that may even venture into suburban or urban backyards.
Foods Ducks Eat
Wild ducks eat a wide range of different foods and they are constantly foraging for meals and snacks. Foods ducks regularly eat include:
- Small fish and fish eggs
- Snails, worms and mollusks
- Small crustaceans
- Grass and weeds
- Algae and aquatic plants and roots
- Frogs, salamanders and other amphibians
- Aquatic and land insects
- Seeds and grain
- Small berries, fruits and nuts
In addition to these nutritious foods, some ducks will also eat sand, gravel and small stones to provide grit that aids their digestion. Grit may also provide trace amounts of critical minerals as part of an overall healthy, varied diet.
How a Duck's Diet Varies
While all ducks are regularly omnivorous and will try many different foods that may be available, the exact diet any duck follows depends on several factors, including:
- Species: Some ducks are specialized for particular types of food, such as mergansers with narrow, toothed bills that eat primarily fish. Perching ducks that live in trees often have a lot of nuts or fruits in their diet.
- Season: Many ducks will have a diet of mostly insects in spring and summer when insects are most plentiful and provide the best protein and other nutrition for growing ducklings. When the seasons change and insects aren't as common, however, ducks will switch their diet to more easily available foods. A duck's diet may vary the most in winter, when they take advantage of any possible food source.
- Range: Where a duck's overall range occurs impacts its diet. Ducks that stay in fields or grassland areas eat more grains and grasses, while ducks that live along oceanic shorelines will eat more fish and crustaceans. When a duck's range changes during migration, its diet will change as well. If food is scarce, a duck's range may change accordingly to find more abundant food sources.
- Habitat: Where a bird lives affects the available food that will make up the majority of its diet. Ducks that prefer shady marsh habitats will eat more amphibians and small fish, while ducks that stay in more open parks and grassy areas are more prone to eat grasses, weeds and grain. Ducks that stay in forested areas, such as the wood duck, eat a lot of nuts.
- Feeding Style: How a duck feeds has a large impact on its diet. Dabbling ducks feed in shallow water and are more likely to have a diet with more aquatic plants and insects, while diving ducks feed deeper in the water and typically eat more fish or crustaceans.
What Ducks Shouldn't Eat
Unfortunately, the food most people associate with ducks – bread – is also one of the worst parts of a duck's diet. Bread is bad for ducks because it lacks any nutritional value for the birds. A diet of mostly bread or bread-like products such as crackers, cookies, chips, cereal and similar scraps will cause health problems, including obesity, malnutrition and poor development. Uneaten, rotting bread in the water will foster disease and attract pests and predators such as rats, raccoons and other mammals that may prey on ducklings or even attack adult ducks. Birders who enjoy feeding ducks should do so only rarely and should offer a range of nutritious foods, such as cracked corn, oats, chopped vegetables and lettuce leaves instead of unhealthy bread.
Another unhealthy part of ducks' diet is lead - specifically, lead sinkers from abandoned fishing line. To a foraging duck, these small round or oblong pellets may look like nuts or seeds, but the toxic effects of the lead can linger in their systems for weeks, leading to debilitating weakness, illness and even death. Fishermen should always collect their discarded fishing line, hooks and sinkers, and should use appropriately weighted fishing line to minimize the risk of breaks that could cause lost sinkers that would tempt hungry ducks.
Ducks are opportunistic eaters and constant foragers that will sample nearly any food, and understanding what ducks eat can help birders keep their local duck habitats and duck feeding areas healthy and nutritious.
Photo – Feeding Mallard © John Haslam