What Do Ducks Eat? Feed, Foraging, and What to Never Give

Author: Elliott Garber, DVM

Ducks eat a complete formulated waterfowl or all flock feed as the base of the diet, plus whatever they find foraging: green plants, insects, snails, slugs, and pond life. Around that base they will happily take greens and vegetable scraps, and they need clean water available whenever they eat. The base ration changes twice in a duck’s life, once from a higher protein starter down to a grower, and once again when a female actually starts laying and needs the extra calcium. That is the whole system. Everything else is detail.

The detail that matters most, and the reason a duck is not simply a chicken that swims, is niacin. Ducklings need considerably more of it than chicks do, and a chick starter formulated for laying hens can leave a duckling with bowed legs and swollen hocks. If you keep ducks and remember one thing from this page, make it that one. If you want the chicken version of this progression instead, our chicken feeding guide covers starter, grower, and layer for a laying flock, and the duck species page collects the rest of the duck guides, including how long ducks live and what shortens it.

The second thing worth knowing before you buy a bag of anything: write down what you feed and when you change it. A ration change is the single most common thing owners cannot remember three months later, when a bird is off form and a veterinarian asks. You can start a free duck profile and log the feed, the switch dates, and the weights in the same place.

Niacin is the difference between duck feed and chicken feed

This is the single most useful thing this page can teach, so it goes first.

Niacin, vitamin B3, is one of the few nutrients where ducks and chickens genuinely part company. Birds can make some of their own niacin from the amino acid tryptophan, and the Merck Veterinary Manual professional edition states that turkeys, ducks, pheasants, and goslings are much more severely affected by niacin deficiency than chickens are, with the higher apparent requirement likely down to their less efficient conversion of tryptophan to niacin. It is a metabolic difference, not a folk belief.

The requirement follows from it. Merck’s professional edition puts the chicken figure at niacin of at least 30 mg per kg of feed to prevent deficiency, notes that many nutritionists recommend two to two and a half times that, and then gives a separate allowance for waterfowl: 55 to 70 mg per kg of feed appears to be satisfactory for ducks, geese, and turkeys. A peer reviewed requirement trial in Poultry Science using mule ducklings on a corn and soy basal diet found the minimum niacin requirement to be 45 mg per kg. Those numbers do not agree exactly, which is normal for nutrient requirements measured in different birds on different diets, and the practical reading is not to chase one figure. It is that a feed built for laying hen chicks sits well under what a duckling needs.

The signs are specific enough to recognise. Merck describes ducks and turkeys with niacin deficiency showing severe bowing of the legs and enlargement of the hock joint, on a background of poor appetite, slow growth, general weakness, and poor feathering. That same Poultry Science trial found that bowed leg disorder was prevented by adding sufficient niacin, or sufficient tryptophan, to the basal diet, and that excess tryptophan could spare the duckling’s need for niacin while excess niacin could not make up for a tryptophan shortage. A duckling that sits down a lot, walks on its hocks, or develops legs that bow outward needs a veterinarian and a feed review, in that order, and the sooner the better because a deformed limb does not straighten once it has set.

What to actually buy

The clean answer is a feed formulated for waterfowl. The extension guidance asks for a duck or waterfowl starter or grower, and that is what to request first. An all flock or flock raiser ration, sold to be fed to several species at once, is the usual substitute in a mixed yard of ducks and chickens. Because the published allowance for ducks is roughly double the chicken minimum, read the label’s niacin figure rather than assuming it, and treat a waterfowl feed as the default whenever your store carries one.

If your feed store does not carry one, poultry extension guidance from Dr. Jacquie Jacob at the University of Kentucky sets out the substitutions plainly. A chick starter or grower is formulated for egg type chicks, which have a lower niacin requirement than ducks, so if you use one you need to add supplemental niacin to the ducks’ water. A broiler starter or grower is formulated for fast growing meat chickens whose niacin requirement is similar to that of ducks, though the protein may run higher than ducks need later in growth. Turkey or game bird starters contain enough niacin, but their much higher protein can be detrimental to ducklings.

On supplementation itself, be aware of what is and is not published. The extension guidance says to add supplemental niacin to the water and stops there, without a dose. Merck gives a target concentration in the feed rather than a spoonful. Brewer’s yeast is the supplement most keepers reach for, and it is a genuine niacin source, but the doses circulating online trace back to books and vendors rather than to any extension or veterinary source we could verify, so we are not going to print a number here and imply it is authoritative. Buy the right feed if you possibly can. If you are supplementing because you have no alternative, or because a bird is already showing leg signs, that is a conversation with a veterinarian who sees poultry, who can dose an individual bird properly.

Feed by life stage

Ducks need the same nutrients as chickens in different proportions, and they eat mainly to meet their energy requirement, so the energy density of the feed decides how much of it they eat. Published protein figures vary more than you might expect, largely because they were measured for different purposes.

Starter. Feed store duck and waterfowl starters commonly run 18 to 20 percent protein, per the poultry extension guidance above. Ducklings being pushed for meat are fed harder: extension advice on raising meat ducks in small and backyard flocks describes a starter mash of 22 to 24 percent protein for the first four weeks, moving to a 20 percent finisher. In the United States that duckling is nearly always a Pekin. Merck’s professional chapter on nutrition in waterfowl, which is written for zoo and collection birds rather than backyard flocks, is higher still at 25 to 28 percent protein and 5 to 8 percent fat for growing birds up to eight weeks. We are not going to average those into a single tidy number, because the spread is real and it reflects what the birds are being raised for.

Grower. The early growth spurt slows fast. Extension notes that research shows no benefit to feeding more than about 16 percent protein in a well balanced feed after two weeks of age, and published duck feeding tables reproduced by extension put growers in the 16 to 19 percent band. In Merck’s waterfowl chapter, collection birds move onto a maintenance ration of 14 to 17 percent protein after twelve weeks. Whatever the exact figure, the direction is down.

Layer or maintenance. Protein stays in a similar range. What changes is calcium, and that change is the one worth getting right.

Calcium: layer feed is for birds that are laying

Duck feeding tables published by poultry extension for ducks kept for egg production in small flocks show the same jump in two independently sourced rations: about 1 percent calcium in the starter and grower, rising to about 3 percent for laying birds. That is roughly a threefold increase, and it is there to build a shell on an egg most days.

Fed to the wrong bird, that calcium is a problem rather than a bonus. Merck’s professional chapter on poisonings in poultry records that excessive calcium intake in broiler chicks produces urolithiasis and visceral gout, with urate deposits on the abdominal viscera and in the joints, and that concentrations above 2 percent will induce those lesions in broilers, while feeding calcium above 3 percent before the onset of egg production induces the same lesions in pullets. Those thresholds were established in chickens, and we have not found equivalent published thresholds in ducks, so treat the exact numbers as the chicken data they are. The principle is not in doubt and it is the same principle the chicken guide describes: growing birds, drakes, and hens on a laying break do not need laying level calcium, and the kidney is what pays for it.

So for a mixed flock, which is what most backyards actually have, the safe default is a lower calcium all flock or grower ration for everybody, with crushed oyster shell offered free choice in a separate dish so the birds that are laying can take what they need. Free choice is doing real work in that sentence: it lets each bird self regulate instead of forcing the drake to eat a layer’s calcium load.

Water belongs beside the feed, not across the yard

This is a safety point, not a nicety, and it is the second real divergence from chickens.

Poultry extension guidance on feeding laying ducks is unusually direct about it: ducks should never be given access to feed without water nearby, the waterer is best placed directly next to the feeder with water available at all times, and without water ducks can choke on their feed. The same body of extension advice on raising meat ducks adds the other half of it, that ducks do not eat as much if they cannot drink, so waterer space limits feed intake.

Drinking water is not the same thing as bathing water, and both matter. The RSPCA knowledgebase on water access for farmed ducks reports that ducks given open water, particularly water deep enough for full body coverage, have better eye and nostril cleanliness, foot condition, and plumage condition, because bathing and preening are how a duck keeps its nares and eyes clear and its feathers waterproofed. A duck can live on a drinker. It does visibly better with something it can dunk its whole head into.

One exception for the very young: extension advice on raising ducklings is to keep them out of swimming water for the first three weeks, because duckling down is not enough insulation to stop them chilling. They still need drinking water they cannot drown in, right next to the feed.

Grit, and when it actually matters

Ducks have no teeth and grind their food in the gizzard, using small hard stones they pick up themselves. Poultry extension’s description of the avian digestive system sets the rule cleanly, in chickens: birds fed only commercially prepared feed do not need grit, while birds that eat whole grains, or are kept on pasture where they do not pick up enough pebbles with the forage, typically do. Extension guidance on feeding geese says the same thing for waterfowl specifically, that grit is required to assist digestion although geese can typically ingest enough small stones from the pasture on their own.

Two practical notes. Grit is not oyster shell. Grit is hard and insoluble and grinds; oyster shell and limestone dissolve and supply calcium. Keep them in separate dishes. And the moment your ducks start eating anything beyond pellets, which for most backyard ducks is immediately, offer insoluble grit free choice and stop thinking about it.

What foraging really contributes

Ducks are good foragers and genuinely enjoy the work. Poultry extension puts the value of it honestly: if allowed to forage for green plants, insects, snails, slugs and so on, most ducks can obtain their minimal nutritional requirements, but on forage alone, production for either meat or eggs will be low. Extension also notes the obvious scaling problem, that as flock size rises the amount any given patch of ground can supply per bird falls.

So treat forage as a real and worthwhile part of the diet that reduces the feed bill and gives the birds something to do, not as a replacement for the ration. Slugs and snails in particular are what ducks are famous for in a garden, and they are genuinely eating them, not just trampling the lettuce.

Greens and vegetables are fine as extras on the same terms. The Merck waterfowl chapter notes that collection birds on complete pellets are usually offered some lettuce anyway, for psychological stimulation and to mimic natural foraging, which is a good way to think about greens generally: enrichment that happens to be food. Chopped leafy greens, peas, cucumber, and similar vegetables are all reasonable. What matters is that they stay a topping rather than the meal, because the same Merck chapter is blunt that diets of only bread, lettuce, and corn lead to deficiencies of protein and multiple vitamins, showing up as poor plumage, swollen joints, and pododermatitis.

The things that genuinely hurt ducks

Mouldy feed. This one is worse for ducks than for chickens, and it is the danger most likely to be sitting in your own feed bin. Merck’s professional chapter on aflatoxicosis in poultry states that susceptibility varies and that ducklings, turkeys, and pheasants are susceptible while chickens, quail, and guinea fowl are relatively resistant. The chapter on poisonings puts it the same way: all poultry are susceptible, but ducks and turkeys are particularly sensitive. Aflatoxins are produced by moulds in the feed, primarily damage the liver, and hit growth, feed conversion, egg production, shell quality, fertility, and hatchability. Buy feed from somewhere with turnover, store it dry and sealed, and throw out anything caked, musty, or warm rather than feeding it to the flock.

Stagnant water and decaying matter, because of botulism. Merck’s chapter on botulism in poultry, which carries the old name western duck sickness for good reason, describes the toxin producing clostridia as saprophytes living in soil, freshwater wetland sediments, and decaying organic matter, needing anaerobic conditions and a temperature of 25 degrees Celsius or above to produce toxin, which is why most waterfowl outbreaks happen in summer and autumn. Massive mortality events can occur in waterfowl. The US Geological Survey National Wildlife Health Center describes how the toxin concentrates in aquatic invertebrates that filter feed sediment, so a bird eating them gets a concentrated dose, and how maggots feeding on a dead bird can carry it on to the next. Signs are weakness and an inability to hold up the head, which in water leads to drowning. Practically: do not let a duck pen develop a warm stagnant puddle in high summer, refresh bathing water, and pick up any dead bird promptly. Merck names rapid and proper disposal of dead carcasses as the most effective method in a waterfowl outbreak, and the survey warns that a single carcass left in a wetland can prolong one.

Salty human food. In the same poisonings chapter, Merck notes that birds under 21 days old are more susceptible to sodium because their kidneys cannot excrete it efficiently, and gives a duck specific figure: 2 percent salt in the feed, or 4,000 parts per million in the water, depresses growth in young ducks and lowers fertility and hatchability in breeding stock. Signs include laboured breathing, lethargy, fluid filled abdomens, and watery droppings. Crisps, salted popcorn, cured meat, and seasoned leftovers are not treats.

Avocado, on the honest terms. The Merck chapter on avocado toxicosis records myocardial necrosis in birds and mammals, names chickens and turkeys among susceptible species, and adds that caged birds seem more susceptible while chickens and turkeys seem relatively resistant. Ducks are not specifically listed either way, and leaves are the most toxic part. That is thinner evidence than the confident lists online suggest, so the honest position is that avocado has killed birds, nobody has established a safe dose for ducks, and there is no reason to find out. Keep it away from the flock.

The bread question, answered properly

Bread is the thing everyone asks about, and the usual answer is right for the wrong reason, which is worth untangling because the wrong reason has become an article of faith.

Bread is a poor food for ducks. That much is solid. New York State’s Department of Environmental Conservation says plainly that the items people commonly feed waterfowl, bread, corn, and popcorn, are low in protein compared with the natural foods waterfowl eat. And Merck’s waterfowl chapter says diets of only bread, lettuce, and corn lead to deficiencies of protein and multiple vitamins. Note what both are saying: the problem with bread is too little protein and too few vitamins, filling a bird up with nothing much.

Now the part that is repeated everywhere and holds up less well. Bread is widely blamed for angel wing, the deformity where the last wing joint twists and the flight feathers stick out sideways instead of lying flat, usually on the theory that bread supplies too much protein and energy and drives the feathers to outgrow the joint. The Merck waterfowl chapter does connect angel wing to excessively rapid growth in large waterfowl, which is the seed of the idea. But when you look at what has actually been studied in domestic waterfowl, the published work points elsewhere. A genome wide association study in Pekin ducks identified nine SNPs across five chromosomes associated with the trait and stated outright that the genetic basis remains poorly understood. Work in White Roman geese found incidence and severity differed significantly between genetic lines while stocking density did not significantly change them, concluding that genetic selection generally aggravates the condition, though those authors still recommended keeping stocking density below current commercial practice. A later heritability study in the same breed estimated liability heritability at 0.39 in a line selected for heavy body weight, where incidence ran above half the birds, and concluded that selecting for heavy body weight may concomitantly select for angel wing. And in Muscovy ducks, researchers reproduced angel wing experimentally by infecting birds with goose parvovirus, and reported it as, to their knowledge, the first viral cause described in waterfowl.

None of that exonerates bread, and none of it is a study of bread. That is exactly the point. The literature that exists on angel wing in domestic waterfowl is about genetics, growth rate, and at least one infectious agent, and we could not find a controlled study establishing bread as a cause. On top of that, the popular mechanism runs backwards: bread is blamed for supplying too much protein, while the authorities above describe bread heavy diets as supplying too little.

So the practical advice does not change, but the reason does. Do not make bread a staple, for ducks of your own or for ducks in a park, because it displaces a balanced ration with something low in protein. Be sceptical of anyone who tells you a slice of bread will deform a wing, and be equally sceptical of anyone who uses the weak angel wing evidence to argue bread is therefore fine.

Feeding wild ducks is a different question from feeding yours

Your own flock is a managed, closed system. You control the ration, the storage, the water, and the stocking density, and you can weigh the birds and change what you are doing. A park pond is none of those things, and that is why the advice diverges.

State wildlife guidance is consistent about the reasons, and they are not primarily about the nutrition of one bird. New York’s Department of Environmental Conservation lists poor nutrition alongside disease spread, since birds fed on the ground eat where they defecate and concentrate in unnatural numbers, naming duck virus enteritis, aspergillus from mouldy food, and avian botulism. It also names dependence on handouts and loss of wariness, water quality problems from concentrated droppings, and disruption of normal migration. The botulism point connects directly to the mechanism above: concentrate a lot of waterfowl on a warm shallow pond in late summer and you have built the conditions.

If you want to do something useful for wild ducks, leave them to forage and keep the pond clean. Save the feeding for the birds you are actually responsible for.

Keeping track of what you feed

Feeding decisions get much easier when the history is written down rather than remembered. On a free Creatures animal profile you can log the ration each bird or group is on and the date you changed stages, which is the record you will want when someone asks whether a pullet duck was still on grower when she laid her first egg. Weights and body condition go in as physical measurement records, so a slow loss shows up as a trend line rather than a hunch, and medical records including examinations, medications, and test results are private by default. If a leg problem or a suspected feed issue does end up at a clinic, you can download a printable packet of the animal’s records to take with you, and import the clinic’s PDF back into the history afterwards. Reminders will nudge you about the things that slip, like checking whether the layers actually need the layer feed yet.

Common questions

Can ducks eat chicken feed? For adults, a non medicated grower or all flock ration is workable, and an all flock or flock raiser ration is the better bet because it is sold to be fed to waterfowl alongside chickens. For ducklings, a standard chick starter is built for egg type chicks with a lower niacin requirement, so extension guidance is that you must add supplemental niacin to the water if you use one. Layer feed is the one to avoid for anything that is not currently laying, because of the calcium. Be aware that Merck’s waterfowl chapter takes a firmer line than the extension advice does: it says feeding waterfowl a chicken starter, grower, adult maintenance, or layer pellet is not advised, because those pellets generally carry less protein and lower vitamin and mineral supplementation than waterfowl require. Treat a chicken ration as the workaround, not the plan.

Should I buy medicated chick starter for ducklings? Default to unmedicated. Poultry extension states that ducks do not normally need medicated feed because they are resistant to most common avian diseases, and that medicated chicken feed can be toxic to waterfowl because the medication is dosed for the amount a chicken eats while a duck eats more feed. Being straight about the evidence: ducks do carry coccidia, and Merck lists Tyzzeria perniciosa as a known duck pathogen with dramatic outbreaks recorded in wild ducklings two to four weeks old, while also noting that amprolium has a safety margin of roughly eight to one at the highest recommended feed level in chickens. We could not verify a primary toxicity study in ducklings from either direction. What settles it in practice is simpler: a medicated chick starter is still a chick starter, so it is the wrong niacin level anyway, and there is no upside to accept the uncertainty for.

What about oyster shell for laying ducks? Yes, offered free choice in a separate dish rather than mixed into the feed, so non laying birds and drakes can leave it alone. It is a calcium source, not grit, and does not replace insoluble grit.

How much do ducks eat? Published extension figures put laying ducks at roughly 120 grams, about a quarter of a pound, of feed per bird per day, varying with how much they lay and how much foraging is available. Meat ducks eat around three pounds of feed for each pound of weight gained.

Do ducklings need a pool to eat properly? No, but they need drinking water within reach of the feeder at all times, open enough that they can scoop and shovel water into their bills and shallow enough that they cannot drown. Swimming water can wait until about three weeks, once they are better insulated.

Do this next on Creatures

Set up the flock and log the ration. Give each duck, or the group, a free profile with Add an animal, then record the feed, stage switches, and weights with Add a record. The record sheet opens for visitors to look around, and a free account is what saves what you enter. Start with adding an animal and adding a record.

Keep the health picture together. Weights, leg problems, and vet visits all sit under health and medical records, and reminders and upcoming care will prompt you about the checks that slip. The profile tabs guide shows where each of those lives.

Looking for ducks. Browse ducks on the Creatures marketplace and search trusted breeders in the breeder and rescue directory. If the breed you want is not listed near you, set a listing alert for ducks and you will hear when one appears. No account needed to start. See saving searches and using your watchlist.

Breeding or selling ducks yourself. Add your operation with Add a breeder profile so buyers can find you, then read getting listed in the breeder directory.

Read more on ducks. The duck species page collects the breed and care guides, how much a duck costs covers the money side, and the Pekin and Muscovy pages cover the two breeds most backyard keepers start with.