We have two roosters that have showed up in the park next to our home lately. We live in Mililani where the association rules forbid keeping fowl on your property. (gonna tell the wild roosters they are in violation, LOL).  They are busy all day "raking" leaves and debris from the trees, searching out roaches, centipedes, etc.......a good thing, I say. But they do crow in the morning before daylight on most days. I say let them be, they are not hurting anything, and there are no native birds the chickens are harming.