you look at his spurs to see how old he is
If they have a comb
A rooster is never too old to crow, he just might not do it as often.
A male chicken is called a rooster. You can tell if it is a rooster or not once they are 4-6 months old. When they get to that age they will 1. Start to crow. 2. Grow spurs. ( Things on the back of their legs) and 3. Grow a comb.
at about 8 weeks old or so they start developing small differences. For example, their cones on the top of their head might be bigger, they might have longer tail feathers, and they might have a broader chest. They might be more aggressive, or even start to rooster when they are young. if they rooster, they are a rooster- and it is loud and might be obnoxious.
The rooster is a mature adult chicken - there's no other term in common use for it.
Some breeds, known as sex links, can be sexed at birth however the methods vary depending on the breed. Generally speaking, the combs of the roosters will be larger than that of hens of the same breed. By the time a rooster is about 4-6 months old you should hear them crow, which is the one way to tell for sure as hen don't crow.
the colors are different.
Inorder for a rooster to be a teen, it must be between the ages of thirTEEN and nineTEEN
not very old
A rooster is an adult. When a male chicken or cockerill is mature he will be a rooster. Therefore roosters are fertile. Cockerills are not- like little boys.
Look at the related answers.
A cockrel is a male chicken under a year old and a rooster is a male chicken that is older than a year.