I herd my ducks. I walk slowly towards them with my arms spread wide (you can even carry a broomstick or something long to make your reach even wider). I shine a light into their house. I walk slowly towards them and towards their house until they are all inside and I shut the door behind them. They have learned the routine. They don't put themselves to bed at night like the chickens, but if they see me come out after dark, most of them will run into their house.