Ducks, particularly the upright Indian Runner and the Khaki Campbell, hunt slugs and snails in damp ground with less soil disturbance than chickens, which makes them suitable for growing areas with tall crops such as corn and trellised beans. Release them at dusk or after rain, keep them out of seedlings and low leafy crops they will trample or eat, and give them water to drink and to rinse their bills.
A duck patrol is the managed grazing of ducks through crop areas to remove slugs and snails.
Why Ducks, Not Chickens
Slugs are the main pest of seedlings in wet climates and cannot be eliminated by rotation, since they feed on almost every green plant (Pest Disruption). The carrier names runner ducks and Khaki Campbells as excellent slug and snail hunters. Their flat bills do little damage to soil, and they do not scratch as hens do, so they can work in a growing bed that a chicken would tear up. They are most active when it is damp, which is when slugs are.
Method
Step 1: Choose the crop. Tall, established crops (corn, trellised beans, brassicas past the seedling stage) are suitable. Leave out seedlings, lettuce, strawberries and low leafy crops, which ducks eat or trample.
Step 2: Time the patrol. Release the ducks in the evening or after rain, when slugs are out, and shut them up at night against predators (Predator Protection).
Step 3: Limit the time. A few hours at a time. Watch the ducks and the plants; take ducks out if they start on the crop.
Step 4: Give water. Ducks need water deep enough to dip their bills and clear their nostrils. A tub or trough will do; a pond adds mess and risk.
Step 5: Rest the patch. Rotate through the beds so the ducks do not foul one spot.
Step 6: Count the slugs. Check damage and trap catches before and after (Monitoring and Identification); keep the patrol only if slugs fall.
What The Ducks Cost
- Feed: ducks forage but usually need supplementary grain (Poultry Keeping covers poultry in general).
- Trampling and eating of low plants.
- Wet droppings, including near water sources; keep them away from wells.
- Shelter and night protection.
How many ducks are needed per bed depends on slug density, weather and the crop. The corpus gives no figure, so begin with a pair, and observe.
Slugs And People: Wash Greens
Slugs and snails can carry rat lungworm (Angiostrongylus cantonensis), a parasite that people catch by eating raw slugs, snails or produce contaminated with their slime. It is established in parts of Asia, the Pacific and the southern United States. Where it occurs, wash leafy greens thoroughly, check for slugs in salad, and do not let children handle slugs.
Wash hands and greens after slug control
Wear gloves when picking slugs and wash hands afterwards. Cook or wash leafy vegetables carefully if rat lungworm is known in your region. Wash hands after handling ducks and their droppings, which can carry Salmonella.
Common Mistakes
- Letting ducks into seedlings. They eat them.
- Leaving ducks out overnight. Predators take them.
- No water. Ducks cannot swallow dry food without water to rinse their bills.
- Expecting zero slugs. Ducks reduce numbers.
What’s Next
- Learn next: Plant Disease Management — the other half of crop protection
- Combine with: Chicken Tractors for Pest Reduction — chickens between crops