What Do Ducks Eat? Complete Feeding Guide for Australian Duck Keepers

Feeding ducks well is foundational to everything you want from them — good egg production, fast meat growth, healthy feathers, strong immunity, and long productive lives. Yet duck nutrition is one of the most misunderstood aspects of keeping ducks. Many first-time duck keepers either feed inappropriately (bread, scratch grains, inadequate protein) or assume ducks can fend for themselves given enough space. Both approaches lead to nutritional deficiencies, reduced production, and compromised health.

This complete feeding guide covers the nutritional principles behind duck feeding, the role of commercial feeds, what supplementary foods ducks thrive on, what they must never eat, how feeding changes across life stages, and how Australia's climate and seasons should inform your feeding approach.

How Ducks Eat: The Mechanics

Before getting into what ducks eat, it's worth understanding how they eat — because their physical feeding mechanisms are quite different from chickens.

The bill as a filter: The duck's broad, flat bill is equipped with lamellae — comb-like structures on the inside edge that act as a filter. In the wild, ducks scoop water and substrate, filter out food particles (invertebrates, seeds, plant material), and expel water. This filter-feeding mechanism is central to duck biology.

Water required for swallowing: Ducks cannot safely swallow dry feed without water. They load their bill, then wash the food down with water. This is not a preference — it is a physiological necessity. A duck without access to water alongside its feed will reduce feed intake significantly, stop eating dry pellets entirely, or attempt to swallow dry feed and choke or develop impacted crop.

Practical implication: Water must always be available immediately adjacent to the feed station. Not across the yard, not in a separate paddock — right there, within bill reach of the feeder.

The duck as a soil prober: Ducks also feed by probing soft soil, mud, and aquatic sediments with their bills, extracting invertebrates, worm castings, insect larvae, and other organisms. In a garden or orchard setting, this is a significant and valuable food source. In a confined run, it means ducks will quickly turn any soft-floored area into a muddy probing zone.

Core Nutritional Requirements

Duck nutritional requirements are broadly similar to chickens but with some key differences:

Energy

Ducks need adequate metabolisable energy (ME) for maintenance, growth, egg production, and thermoregulation. Duck breeds vary in size and metabolic rate — lighter, more active breeds (Indian Runners, Khaki Campbells) may consume feed more efficiently relative to their body weight than heavier breeds (Pekins, Muscovies).

Protein

Protein — specifically the amino acid profile within it — is critical for: - Feather production (feathers are approximately 85% protein) - Egg white (albumen) production - Yolk proteins - Muscle growth in meat breeds - Immune function and enzyme production

Crude protein requirements by life stage: - Ducklings (0–3 weeks): 20–22% - Growers (3–8 weeks): 16–18% - Adult layers: 15–17% - Adult maintenance (non-laying): 14–16% - Breeding drakes: 15–16%

Key amino acids: Methionine and lysine are the most commonly limiting amino acids in duck diets. Quality commercial waterfowl feeds are formulated to meet these requirements; improvised diets from grain and kitchen scraps frequently fall short.

Calcium

Calcium is the dominant mineral requirement for laying ducks — it is the primary structural component of eggshell. A laying duck deposits approximately 2–2.5g of calcium into each eggshell. Without adequate dietary calcium, production drops and the duck's skeletal calcium is mobilised — leading to fragile bones, weakness, and fractures.

Calcium requirement: 2.5–3% of the diet for laying females; much lower for non-layers and growing ducklings.

Critical warning: Never feed layer pellets (designed for laying hens with ~3.5% calcium) to growing ducklings. The high calcium load damages developing kidneys, causing potentially fatal kidney disease.

Phosphorus

Works with calcium in bone and eggshell formation. Must be in appropriate ratio to calcium (Ca:P approximately 2:1). Commercial feeds are formulated to meet this ratio.

Vitamins

• Vitamin A: Essential for mucous membrane health, immune function, and vision. Found in green leafy plants and root vegetables. Deficiency causes respiratory susceptibility and reduced production.
• Vitamin D3: Required for calcium absorption. Produced by exposure to sunlight; supplemented in commercial feeds for housed birds.
• Vitamin E: Antioxidant; important for immune function and reproductive health. Found in green plants and seeds. Deficiency causes reproductive failure and immune suppression.
• B vitamins (particularly Niacin/B3): Ducks have a higher niacin requirement than chickens. Niacin deficiency in ducklings causes leg bowing and weakness. Commercial feeds formulated for ducks contain adequate niacin; chicken-formulated feeds may be deficient for ducks.

Niacin deficiency is one of the most common nutritional problems in ducklings raised on chicken-only feeds. If using chicken starter (not recommended as a sole feed), supplement with brewer's yeast (rich in niacin): add 2.5–3 tablespoons of brewer's yeast per cup of chick starter.

Minerals

Key minerals beyond calcium and phosphorus: - Sodium and chloride: Electrolyte balance. Found in commercial feeds as salt. - Zinc: Feather and egg development, immune function. - Manganese: Bone development; deficiency causes perosis (slipped tendon) in growing ducklings. - Selenium: Antioxidant function. Selenium deficiency is common in some Australian soils (particularly high-rainfall granitic areas). Supplement through commercial waterfowl feeds or specific supplementation.

Commercial Duck Feeds: What to Buy

Waterfowl-Specific Feeds

The best choice for ducks is a commercial feed specifically formulated for waterfowl: - Higher niacin than chicken feeds - Appropriate calcium levels for ducks - Protein adjusted for duck metabolism

In Australia, dedicated waterfowl feeds are less widely available than chicken feeds. They are available from: - Specialty waterfowl suppliers: Online stores and specialty poultry suppliers - Some rural supply stores: Elders, Landmark, CRT — ask specifically for "duck pellets" or "waterfowl feed" - Some Petbarn stores: In larger urban centres

Prices (2024): $25–$45 per 20kg bag for quality waterfowl pellets.

Using Chicken Layer Pellets

In practice, many Australian backyard duck keepers use standard chicken layer pellets as the basis of their adult laying duck diet. This works reasonably well with the following adjustments:

• Supplement with brewer's yeast or a niacin supplement if chicks or growing ducklings are on chicken starter
• Offer separate shell grit/oyster shell free-choice (as with chickens, to allow self-regulation of calcium intake)
• Add green forage daily to compensate for any vitamin deficiencies

Never use medicated chicken starters for ducklings. The coccidiostat medications (amprolium, monensin) in medicated chicken feeds are metabolised differently by ducklings, which consume far more feed per body weight than chicks, potentially reaching toxic levels.

Feeding by Life Stage

Ducklings (0–3 Weeks)

Feed: Non-medicated waterfowl starter (ideally) or non-medicated chick starter with brewer's yeast supplementation. Protein: 20–22% Management: Feed ad libitum (always available). Ducklings eat frequently and in large amounts for their size. Water: Always available immediately next to feed. Use shallow drinkers or drinkers with a grate to prevent drowning — ducklings are driven to submerge their heads in water and can drown in deep containers. Do not: Use medicated starter; restrict feed access; use layer pellets.

Growers (3–8 Weeks, Meat Ducks)

Feed: Waterfowl grower pellets or non-medicated chick grower. 17–19% protein. Management: Ad libitum feeding for maximum growth rate in meat ducks; slightly restricted for replacement breeding stock to prevent excess fat deposition. Water: Always available. Watch for: Angel wing (outward-twisting wing tip deformity) — associated with excessive protein or energy intake in rapidly growing ducklings. If seen, reduce energy-dense feed and increase fibre (grass, leafy greens).

Growers / Developing Pullets (8–18 Weeks, Replacement Layers)

Feed: Waterfowl developer or maintenance pellets, 14–16% protein. Do NOT use layer feed at this stage — the high calcium will damage kidneys before egg production begins. Management: Ad libitum. Transition to layer: Begin mixing in layer pellets from 16–18 weeks, or when the first egg appears.

Adult Laying Ducks

Feed: Waterfowl layer pellets or chicken layer pellets, 15–17% protein, ~3% calcium. Supplementation: Oyster shell or crushed shell grit free-choice (always available separately from feed). Insoluble grit: Always available if ducks don't have access to natural soil and stones. Feed quantity: 150–200g per duck per day on ad libitum feeding. Production ducks self-regulate well; they won't overeat commercial pellets significantly. Water: Always available, immediately adjacent to feed.

Moult (Typically Autumn)

During the annual moult, ducks stop laying and redirect energy to feather regrowth. Transition to: - Higher protein feed (17–19%) or supplement with protein-rich foods (mealworms, black sunflower seeds, brewer's yeast) - Reduce calcium supplementation for hens not laying - Ensure adequate zinc and sulphur — both important for feather keratin synthesis

Non-Laying Adults, Drakes, and Maintenance Birds

Feed: Maintenance pellets at 14–16% protein, lower calcium. - Do not feed drakes or non-laying ducks on layer pellets as a staple — the high calcium of layer formulations is inappropriate and can cause kidney issues long term. - If the flock is mixed (layers and non-layers), a compromise of feeding layer pellets at 15–16% protein with calcium available free-choice (not in feed) allows all birds to self-regulate.

What Ducks Can Eat: Safe Supplementary Foods

Supplementary foods add dietary variety, improve gut health, provide environmental enrichment, and can meaningfully reduce commercial feed costs when freely available.

Excellent Supplementary Foods

Leafy greens: Silverbeet, kale, chard, spinach, lettuce (not iceberg primarily), endive, chicory, comfrey — all excellent. Ducks relish leafy greens and they provide vitamins, minerals, and fibre. Chop for ducklings; toss to adults whole or roughly torn.

Garden greens: Grass clippings (not from chemically treated lawns), weeds (chickweed, dandelion — highly nutritious), lawn in general (ducks graze pasture readily).

Vegetables: Pumpkin and squash (whole or chopped — ducks will peck through the skin), zucchini, cucumber, tomatoes (ripe), peas (fresh or frozen — excellent), broccoli, corn (cobs or kernels).

Fruit: Watermelon (a summer favourite — ducks relish the flesh and the rind), strawberries, grapes (cut in half), berries, banana, mango, pawpaw.

Grains (cooked or soaked): Oats (rolled or whole, soaked overnight), cooked rice (plain), cooked barley or wheat.

Aquatic plants and organisms: If you have a pond, aquatic plants (duckweed is nutritionally excellent), aquatic insects, and small crustaceans are natural duck food.

Mealworms: Live or dried mealworms are an excellent high-protein treat. Particularly valuable during moult when extra protein supports feather regrowth.

Insects and invertebrates: Ducks will hunt and eat beetles, flies, grasshoppers, slugs, snails, earthworms, and most other invertebrates they encounter foraging. These are natural, high-quality protein sources.

Scratch Grains

A mix of cracked corn, wheat, barley, and millet. As with chickens, scratch is a treat and an enrichment tool, not a dietary staple. It is: - Low in protein and vitamins relative to commercial feed - Filling without being nutritionally complete - Better offered in the afternoon (after ducks have consumed their commercial feed earlier in the day) - Limited to 10–15% of total daily feed intake

What Ducks Must Never Eat

Biosecurity Law: No Meat or Meat Byproducts

Under the Biosecurity Act 2015 (Commonwealth) and equivalent state legislation, it is illegal to feed kitchen waste containing meat or meat products to poultry in Australia — including ducks. This applies even in small backyard situations. The intent is to prevent introduction of exotic diseases (Foot and Mouth Disease, African Swine Fever) via contaminated food waste.

Prohibited kitchen scraps include: Any meat or poultry, fish or seafood, bones, soups or dishes containing meat, processed foods containing meat derivatives.

This is not optional. Penalties apply under biosecurity legislation.

Genuinely Toxic Foods

Avocado: All parts — flesh, skin, pit, and leaves — contain persin, which causes heart failure and rapid death in ducks. Australia's widespread home avocado growing makes this a real risk. Never feed avocado to ducks under any circumstances.

Chocolate and caffeine: Theobromine and caffeine are toxic to ducks (and most birds and mammals).

Onion and garlic (large amounts): Thiosulphate causes haemolytic anaemia in sufficient quantities. Occasional small amounts unlikely to cause harm, but deliberate feeding should be avoided.

Raw or dried beans (uncooked kidney beans in particular): Contain phytohaemagglutinin at toxic concentrations. Always cook beans fully before offering.

Green or raw potato and potato/tomato plant material: Solanine toxicity. Cooked potato is fine; raw green potato and plant material from the nightshade family should be avoided.

Rhubarb leaves: High oxalic acid — toxic. The stem is safe in small quantities; the leaves are not.

Mouldy or spoiled food: Aflatoxins and other mycotoxins in mouldy grain, bread, or produce can cause serious liver damage and death in ducks. Never feed mouldy food.

Heavily salted foods: Crackers, chips, popcorn, processed foods — ducks have low salt tolerance and excess sodium causes osmotic stress and kidney damage.

Bread (large amounts): Not toxic, but nutritionally almost worthless and causes "angel wing" in ducklings when fed in quantity. Occasional small amounts to adult ducks are not harmful, but bread should never be a regular or significant part of the diet. The popular practice of feeding bread to ducks in parks is a genuine welfare problem for wild waterfowl.

Water: The Most Important Nutrient

Water is not a supplement — it is the most critical nutrient in a duck's diet. Ducks require water for: - Swallowing feed (physiological necessity — see above) - Nasal hygiene: ducks must regularly submerge their nostrils and blow water out to clear their nasal passages. Without this, nasal blockage and respiratory infection follow. - Digestion and metabolism - Thermoregulation (particularly in Australian summer heat) - Eye hygiene: ducks moisten their eyes and wash their face in water - Preening and feather maintenance

Daily requirements: - Standard laying duck: 250–500ml per day in moderate weather - In summer above 30°C: 500ml–1 litre per day - A flock of 6 ducks on a 35°C day needs up to 6 litres of fresh, clean water

Water quality: Clean, fresh water changed daily (or more frequently in summer). Ducks foul their water quickly. Biofilm and algae in warm, stagnant water harbour pathogenic bacteria. Rinse drinkers and troughs daily; scrub weekly.

Deep enough for nasal hygiene: Ducks need to submerge their entire bill and nostrils in water — a nipple drinker does not meet this welfare requirement. Provide water at least 5–8cm deep. A simple heavy-duty plastic tub, livestock trough, or automatic float drinker works well.

Feeding Tips for Australian Conditions

Summer: Reduce energy-dense feeds slightly. Offer cool, moist treats (frozen peas, watermelon, cold leafy greens). Ensure unlimited cool, shaded water. Ducks may reduce feed intake in extreme heat — this is normal; ensure water is prioritised.

Winter: Increase feed slightly, particularly scratch grains in late afternoon, as digestion generates body heat. Ensure water doesn't freeze in cold southern Australian conditions (alpine areas, Canberra, parts of Victoria and Tasmania).

Drought: When pasture is dry and foraging is limited, commercial feed becomes the primary nutrition source. Don't assume free-ranging ducks are supplementing adequately when pasture is bare — increase commercial feed allocation accordingly.

Wet seasons (northern Australia): High humidity and wet conditions promote mould growth in feed. Store feed in airtight, vermin-proof containers. Check feed before offering for any sign of mould or damp clumping.

Summary Feeding Plan

Always available for all ducks: Fresh, clean water immediately next to feed; insoluble grit; for laying females, oyster shell free-choice.

Feed your ducks well and they will reward you generously — whether in rich, large eggs, fast-growing table birds, or simply the vitality and activity of a healthy, well-nourished flock exploring your backyard.