I have ducks. Specifically, wood ducks and call ducks. Ducks are the messiest creatures on the face of the earth!! But I love them anyways

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I go on weekend trips sometimes. If you wanted to go out for longer trips, this is what I would recommend:
Buy several kiddie pools for the ducks. Fill them all up before you leave. The ducks WILL mess up the water in all the pools, but that should be enough water for 2-3 weeks. Also, find out how much food they eat in 2-3 weeks, and fill up the feeder accordingly. The only problem with this plan is, what do you do during winter when the water freezes up? I don't think you would like to go on a long trip, with water heaters plugged in the pools. I know I would worry the whole time.
Of course, you can always dig a small pond, and then there would always be water for the ducks. I don't know what your land or situation is, but leaving for a few weeks can be done. As long as you provide enough water and food for them.
That being said, if you have access to somebody with an incubator and duck eggs, this is what you want to do....get a duckling fresh out of an incubator, a few hours after it hatches. It will imprint on the first thing it sees, which hopefully, will be a person (preferably you or your daughter!) Then, hold the baby every day, sit on the couch and watch tv with it, keep it indoors in a heated box/cage, so it feels like part of the family. Ducks are very loving if they are raised with people, and you might even find that you can take the duck with you on your trips. Do a search on "call ducks"--they are just the cutest, sweetest little ducks you'll ever see. They are tiny and would be small enough to carry on trips with you.
http://i96.photobucket.com/albums/l1...s/P1040548.jpg
Here's a pic from a few years ago. Look how tiny the duck is--and he's full grown!