Chickens are birds. So any rules regarding birds would apply to them as well as the parrot, parakeet, other exotics, doves, raptors of any kind or pigeons that are kept by many city dwellers. So in order to discriminate against certain birds they had to come up with things like Poultry. I often wonder why anybody with a checkbook can bring home flocks of very very noisy parrots but it takes an act of congress to allow anyone to have a chicken. I personally knew of one lady that had over 30 exotic birds in a rented apartment and nobody could do a thing about it. the place stunk to high heaven and the humidity was unbelievable. In some places it was actually causing the paper from the sheetrock to peel off. I am looking into this myself to see if Grey Jungle Fowl fall into one of those blessed catagories that have no regulation.