I am trying to understand the metaphor "wet my beak" from the famous American movie "The Godfather: Part II".
In the film a local mafia boss in New York City tells the protagonist (an Italian immigrant who has just begun to experiment in crime):
Young man, I hear that you and your friends are stealing goods...
You should let me wet my beak a little.
wet one's beak
(idiomatic) To drink a beverage. [quotations ▼]
(idiomatic, gangster slang) To take one's share from the financial proceeds of illicit activity
So, I understand that the mafia boss is saying that one wants to take his share from the financial proceeds of illicit activity. However, I an still unclear on the idea behind this metaphor.
Why is the mafia boss likening himself and the protagonist to birds? Why not some other animal, like dogs, wolves, bears, etc?
If they are birds and the water is their financial proceeds of illicit activity, then is the protagonist taking a bird bath?