Reference article
Duck Care
Flock ducks need food, sleep, toilets and company. Their needs and thoughts show you what to improve in the village.
Food
Feed ducks through the bag or 
Cooking, and fill 
Basic Seed Dispenser or 
Super Seed Dispenser so they can help themselves. Growing crops and catching fish gives you ingredients for better meals. A Cooking Pot also slows hunger loss.
Sleep
Give every resident a home and keep its entrance clear. Ducks head to bed around sunset and recover while sleeping. A completely exhausted duck can fall asleep outside, where recovery is slower.
Toilets
Build accessible 
Toilet facilities. If one blocks, a duck needs a plunger from the Janitor Station to clear it. More toilets help when several ducks need to go at once.
Happiness and thoughts
Ducks enjoy company and can become friends. Their thoughts describe things that made them happy, sad or frustrated, including hunger, exhaustion and jobs they cannot carry out. Check the thought history when a resident seems unhappy. Decoration and village improvements give you more ways to make a home for the flock.