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Do Ducks Eat Fish? The Surprising Answer!

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Black-headed duck in the water

Ducks are omnivores, and they eat a wide variety of food, including fish and fish eggs. Diving ducks and Mergansers especially eat a lot of fish since they have evolved to dive deep in the water for fish and crustaceans. 

To learn more about the duck’s diet and eating habits, keep reading. This article takes a close look at what ducks eat and which duck species are most likely to eat fish.

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Do Ducks Eat Fish? Yes!

Ducks are known omnivores, which means they eat both animal matter and plant matter. As waterfowl, ducks often have plenty of access to fish, and ducks eat both fish and fish eggs as a result. Not all ducks eat fish regularly, though.

In fact, Mergansers are the only ducks that have been streamlined to eat fish regularly. These ducks have a specific bill that makes them more capable fishers. These ducks eat fish much more commonly than other duck species.

For example, Mallards and other similar species mainly prefer insects, algae, and plant matter. Because of their beak shape, fishing is not necessarily the duck’s most efficient form of sustenance. Although these ducks will eat fish, they don’t eat fish as regularly as Mergansers.

Duck Eating Fish
Image Credit: FotoRequest, Shutterstock

What Else Do Ducks Eat?

In addition to fish and fish eggs, ducks eat a wide range of food. Ducks are known to eat seeds, grasses, grains, crustaceans, insects, worms, and algae. The specifics of the duck’s diet are largely dependent on the duck species and environment.

What Size Fish Can Ducks Catch?

The size of the duck determines how large of a fish the duck can eat. Smaller ducks, such as Mallards, mainly only eat small fish, like minnows and guppies. Larger ducks have been known to eat chubs, brown trout, and other species.

The reason why the duck’s size determines the type of fish it eats is that ducks swallow their food whole. If the duck knows that it might not be able to swallow the fish whole, it will not catch it.

northern pintail ducks in the lake
Image Credit: Piqsels

Should I Feed Wild Ducks?

Although it may be tempting to toss some treats to ducks, it’s best to avoid doing so. Many snacks that are frequently fed to ducks are actually bad for the creatures. Not to mention, feeding wild ducks makes them dependent on humans, which means they might not be able to survive on their own.

Instead, allow ducks to take care of themselves. Because they can eat fish, plants, and everything in between, ducks do not need help staying healthy.

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Once again, all ducks are known to eat fish, though some duck species eat fish more frequently than others. The size of the fish is determined by the size of the duck.

In addition to fish and fish eggs, ducks eat many other food types, including seeds, grasses, grains, insects, and crustaceans. Because ducks are such capable hunters and gatherers, there’s no need to feed wild ducks you see at the park or in other areas.

Featured Image Credit: Rob Jansen, Shutterstock

About the Author Robert Sparks

Robert’s obsession with all things optical started early in life, when his optician father would bring home prototypes for Robert to play with. Nowadays, Robert is dedicated to helping others find the right optics for their needs. His hobbies include astronomy, astrophysics, and model building. Originally from Newark, NJ, he resides in Santa Fe, New Mexico, where the nighttime skies are filled with glittering stars.