" A rooster (also called a cockerel or cock) is a bird. In actuality, it is a male chicken (Gallus gallus), while the female is called a hen.
Immature male chickens less than one year old are called cockerels. The term "rooster" originates in the United States, and the term is widely used throughout North America, as well as Australia and New Zealand. In the United Kingdom and Ireland the older term "cockerel" is more commonly used. "
"Cock" is in general use as the name for a male of other species of bird, for example "Cock sparrow". "Roosting" is the action of perching aloft to sleep at night, and is done by both sexes. The rooster is polygamous, but cannot guard several nests of eggs at once. He guards the general area where his hens are nesting, and will attack other roosters that enter his territory. During the daytime, he usually sits on a high perch, usually 3–5 feet off the ground to serve as a lookout for his flock. He will sound a distinctive alarm call if predators are nearby.