Can Ducks Eat Apples?

Yes to the flesh, no to the core. Apple is on every duck treat list, and the pips are on the Open Sanctuary Project’s toxic list, because apple seeds carry a compound that releases cyanide when crushed. The amount in a few pips is small — the problem is real but proportionate — and the fix costs nothing: core the apple, then cut it small.

The short answer

Metzer Farms, a California duck hatchery, names apples with strawberries, blueberries, grapes, bananas, peaches and pears as “amazing treats for your ducks”, to be cut “into bite-sized pieces”. The Open Sanctuary Project’s duck diet guide lists “Sliced Apples – no seeds or cores”, and its page on things that are toxic to ducks explains the second half of that: “Apple seeds, and stones/pits in apricot, cherry, peach, pear, and plums contain the toxin.” The toxin is cyanide, delivered by a natural compound called amygdalin. The RSPB’s general advice for garden birds is the same in spirit — fruit “such as apples and pears” is welcome, “but don’t use anything mouldy or salty.”

The seeds, honestly

Apple pips contain amygdalin, a cyanogenic glycoside. A 2015 study in Food Chemistry measured it in the seeds of fifteen apple varieties and found “1 mg g-1 to 4 mg g-1” — one to four milligrams per gram of seed — noting that “action by endogenous plant enzymes can release hydrogen cyanide causing potential toxicity issues for animals including humans.” The ASPCA’s entry for the apple tree, written for dogs, cats and horses, says that “stems, leaves, seeds contain cyanide, particularly toxic in the process of wilting.”

Now the proportion. The US National Capital Poison Center puts the yield at “approximately 0.6 mg of hydrogen cyanide per gram” of seeds, adds that “the seeds are protected by a hard outer shell”, and concludes for people that “you would need to chew or grind hundreds of seeds and swallow them to release enough hydrogen cyanide to cause toxicity.” A duck does not chew, so a swallowed pip mostly passes intact — but a duck is also a fraction of the size of a person, the Merck Veterinary Manual gives the acute lethal dose of hydrogen cyanide in most animals as “approximately 2 mg/kg”, and a gizzard full of grit is a grinder. Nobody has measured any of this in ducks. Open Sanctuary says remove the seeds and Metzer says cut the fruit small; removing them takes ten seconds, so remove them. The fuss stops there.

What is in an apple for a duck

Per 100 grams of raw apple with skin, the US Department of Agriculture’s reference data give 85.6 g water, 52 kcal, 10.4 g sugars, 0.26 g protein and 2.4 g fibre, with 107 mg potassium, 4.6 mg vitamin C and 6 mg calcium. That is a middling fruit: sweeter than strawberries, less so than grapes or bananas, and with the lowest protein of any fruit in this series. The fibre is the useful part. A complete duck feed runs at 16 to 20 per cent protein; an apple is a quarter of one per cent. It is a treat and nothing else.

How to feed apples to ducks

Core it. Cut the flesh into pieces a duck can swallow whole — small dice for a small breed, chunks for a Pekin — because ducks do not chew and a wedge of hard apple is a lodging risk in a way a slice of banana is not. Leave the skin on if the apple is washed; the skin carries the fibre. Grated apple is the easiest form of all for a mixed flock. Apples sit eighth on the Environmental Working Group’s 2026 list of produce with the most pesticide residue, so wash them, or peel conventionally grown ones.

Cooked, unsweetened apple — a spoon of plain stewed apple — is fine and easy on an old bird. Apple sauce from a jar usually carries sugar; check the label or make your own. The tenth-of-the-diet rule applies as always (Colorado State University Extension: treats “no more than 10% of their daily diet”). A few pieces per duck, not an apple each.

When apples are a problem

Whole apples, for the core and the size. Windfalls that have been on the ground long enough to ferment or grow mould — ducks are unusually sensitive to mould toxins — and a flock ranging under an apple tree in autumn will find them, so rake up. Apple pie, apple cake, toffee apples and dried apple rings bring sugar, fat and sometimes salt that a duck should not have. Crab apples are the same fruit in miniature and the same rule applies: flesh yes, seeds no.

The same seed rule covers the stone fruits. Peaches and pears are on Metzer’s treat list for the flesh; the pips and stones of pears, peaches, plums, apricots and cherries are all on Open Sanctuary’s toxic list. The full set is in our can-ducks-eat checker. For the rest of the fruit bowl, grapes, bananas and strawberries have their own pages, and the diet all of it sits on top of is in what do ducks eat.