OMg.....I just had an idea......go out and pin a huge note on them that says this -

Dear Theives,

While we appreciate the fact that you love us enough to take us from our happy home to display us in your yard, please know that we miss our owners. If you don't take good care of us, we will walk back to our own home when you aren't looking!

Signed,
Two Swans

LMAO!!!!!!!!!!!!!!!!!! Sometimes I just quack myself up!!!!!!!!