Survival rate will be less than 15% !!
As a keeper of Chickens in America I know the perils of counting your eggs before they are made into McNuggets. Pretty much every mammal alive loves a chicken dinner and without a fence and properly secured roost the chickens will be killed before they can be sold. So a chicken won't help anyone, but add a shed and some, lets say, chicken wire and you might be on to something.