I have to admit that I had some problem finding an appropriate word for the hero of this song. While Rana's GummiDuckie is colorful, it's definitely an anglicanization; and we certainly can't have that, can we?
Gummi-Ente is both poetic and a correct literal translation, but I don't believe the term is found in actual use in Germany (although I'm not sure whether the hyphen is supposed to be there). The general term seems to be Badewanne-Entchen (bathroom duckling). However, the German Sesame Street albums have it as Quietsche-Entchen (squeak duckling), so that's what we have. The above appears to be the true and correct and authentic Sesame Street translation of the song.
I've sent Wolfgang a link to this thread, so he can give us a clinical opinion.
You'll note that I linked above to the German version of the top 25 hits of Sesame Street. I don't know how long I can live without that CD. It sounds like a real treasure.
-Joe Offer-