Sterling Silver pitcher, shape of bird, beak moves

We came across this silver pitcher at a garage sale. It is approximately 8" tall, and the bill moves when it is tilted. (This is purely decorative. The liquid would pour even if the bill did not move.) It is a heavy piece. It is stamped sterling 990.

There is no maker's mark that we can find. The eyes appear to be jade, but I am not even certain of this.

We would appreciate any information or clues to figuring out what this is.