I am part of a local community that rescues and rehomes animals (dogs mainly but we have also taken in turtles and snakes) and someone brought us a baby Mallard duck today. They said it was found at the doorstep of their apartment, but I really have no other information than that. He looks like he's under a week old. I have absolutely no experience with birds of any kind and I'm not sure what to do with the duck. I have him in a 25 gallon aquarium lined with towels and a heat lamp (safe distance from the duckling) with a small shallow cup of water. The temperature is 93 degrees ( I put a thermometer/hygrometer next to where he is laying). I have no food to offer it except for shredded baby greens and ground oatmeal which is the only thing I had that multiple online sources said are okay for baby ducks to eat. I'm going to Tractor Supply Co. tomorrow to get it food, but my main concern is what to do with the duck. We have many dogs outside and when he gets big he will need to go outside and it won't be safe. Is it legal or beneficial to the duck to release it into the wild when it is ready? Someone told me we could release it and it would instinctually migrate, not sure if this is true. We are handling it as little as possible, but I don't know if it is practical to care for it and feed it and then expect it to be able to fly away and be okay on it's own when it is older. Any advice is greatly appreciated!