What Do Swans Eat? (And What Not to Feed Them?)

Swans are beautiful and graceful birds found in many parts of the world. The family of swans gliding gracefully down the river, male (or male) and female (a pen) followed by a flock of fluffy cygnets never ceases to amaze us.

Swans are some of the largest flying birds, with wingspans of up to 3m. They can easily reach a weight of 15kg and need to eat 25% of their body weight each day. So what do they actually eat?

Swans are primarily vegetarians, so their nutrition comes mostly from plants that grow underwater, but they will occasionally eat insects. This usually happens when small fish, tadpoles, worms, molluscs, fish and frog eggs become entangled in weeds eaten by swans.

The question is, should we humans help them by feeding them? In this article, we’ll cover the basics of swan nutrition and tell you all there is to know about the dos and don’ts of feeding your swan.

Swans mainly eat aquatic plants

What’s the best thing to feed a swan?

Swans can live happily without us feeding them. If you do want to feed them, stick to foods they will naturally seek out, such as:

• whole grains
• corn
• carrots (shredded or chopped)
• bite-sized pieces of spinach and other leafy greens
• lettuce

A flock of swans eating corn

What shouldn’t you feed swans?

Feeding any processed human food to swans can cause nutritional imbalances or cause a potentially dangerous digestive blockage, which can even be fatal.

Never feed any of the following foods to swans:

• Pastries, cakes, cookies, and anything sugary
• raw meat
• cooked bones
• chips and other fast food
• Potato chips and other salty, highly processed snacks
• chocolate
• apple
• onion or garlic
• mushroom
• Dried Beans and Legumes

Also, only offer the small amount of food allowed (in the previous section) and stop feeding once the swan loses interest.

A family of swans eating duckweed

What do cygnets eat?

After six weeks in the egg, the cygnet, or cygnet, emerges into the world with its eyes open and covered in fuzzy down. They are called “precocious,” which means they are relatively mature from the moment they hatch. They’re ready for their first swim in a few days.

They absorb the last of the yolk before they hatch, so they can live without additional food for the first 7-10 days. Egg yolks are rich in nutrients and also have the advantage of being digestible until the cygnets are ready to deal with plants and insects.

But during this time, they will begin to learn how to forage for insects and vegetation. By the time their pantry runs out, they’ll be able to feed themselves, though they may still need help from their parents.

For the first 7 days, they cannot dive underwater (also known as “surfacing”), so any food they eat will be on or under the water. Both parents can help by uprooting the plant from the bottom or “trampling the food.” This involves frantically paddling for a few seconds in shallow water to stir up debris and food that may be lying below for easier capture.

After about two weeks, the cygnets can dive underwater for longer and pull weeds for themselves.

Cygnets watch their mother dive for weeds

Do swans eat fish?

Swans are primarily vegetarian. Although they sometimes eat fish, frogs, insects, worms, and molluscs, this is usually by accident. The victim may just happen to be near a hunk of tasty plant that the swan decides to grab, and doesn’t get away fast enough.

Interestingly, cygnets were more likely to eat animal matter than adults. As they grow, their numbers dwindle, and by adulthood their diet consists almost entirely of plants.

For these reasons, it is neither necessary nor desirable to feed swans with fish. Please don’t do this.

What do swans eat in winter?

In freezing temperatures, the food swans normally forage for may be in short supply, so they look for alternatives such as berries and tubers. If you want to help them out, choose leafy greens like lettuce and spinach and tear them into small pieces.

Swan food pellets with grains, oils and minerals can also be purchased that float on the water.

swans foraging underwater

How do swans eat?

Swans have no teeth. To grind food into a paste, they use a structure called a gizzard, which aids digestion by increasing the surface area for swallowing food.

But even then, swans can extract only a small amount of the nutrients they need. This is why swans need to eat around 25% of their body weight in food every day. A 15kg swan needs to forage 3-4kg of vegetation per day.

Can swans eat bread?

Many of us have fond memories of feeding bread to swans in our local parks and rivers. However, opinions differ widely on whether it is harmful.

A statement endorsed by Professor Christopher Perrins of the Edward Gray Institute of Field Ornithology at the University of Oxford explained that swans have eaten bread for hundreds of years, and there is no evidence that it harmed them in any way – as long as it wasn’t moldy. It may also be an essential tonic during winter when vegetation is scarce.

The other side of the argument is that bread doesn’t provide much nutritional value to the swans, and if they’re full it could mean they’re not getting the nutrients they need to survive and thrive.

Our general advice is not to feed swans bread, but to feed them other foods such as corn, grains and lettuce. These types of food provide more nutritional value to swans.

So if you decide you want to share some fresh bread with the swans, feed them small amounts and stop throwing as soon as they lose interest (or keep throwing and let the ducks take over!).

mute swan diving for food

Can swans eat fruits and vegetables?

Greens such as lettuce, spinach, shredded carrots, celery, and other greens are a helpful addition during the winter, when their typical food sources may be in short supply. Just remember to chop the veggies into small pieces, as swans won’t tear or chew their food.

Fruit is not a natural food for them, and apple peels can be poisonous to swans – so stick with your veggies!

Can swans eat nuts?

Nuts do not form part of a swan’s natural diet, so do not offer them. Or, try throwing some green beans or corn on the ground instead of into the water.

Do swans eat ducklings?

There have been reports of swans attacking mallards and ducklings, but this is likely to be for territory rather than food.