Some people have asked us, probably after a shorter nights sleep than they expected, Why do Roosters crow?

Roosters crow because they're jerks and they want everyone to know that. "Hey, I'm a Rooster; this is my coop; these are my hens that I'm gonna have sex with; go away".

So now if your asking, why do roosters crow at dawn?
The answer is simply that most birds make noise at dawn. Daybreak is when birds are most active; unlike most teenagers you know they have a circadian rhythm that kicks into high gear as soon as it's light outside and once they've perked up they start making noise, mostly territorial calls that let everyone know where their turf is. And the reason roosters are associated with crowing at dawn is probably mostly because roosters are just really loud. The power of a  roosters call can depend on the breed but some cocks crows have been measured at 80-90 decibels, about as loud as a lawnmower or a really big barking dog, and that's twice as loud as the usual chorus of early morning birds that you'd otherwise here. So if you've ever lived near roosters you probably just didn't notice other birds making their morning territorial calls because they're so much quieter. Like most animals you can disrupt a roosters circadian rhythm by keeping it in a dark room for a couple of days. If you were in a dark room for a couple of days with no way of telling when it was day or night you'd probably start keeping  weird hours too. But roosters can also crow at other times of the day and all night, pretty much whenever they want actually. If they hear a loud noise and they think the noise is hear to have sex with their hens they'll crow; if they see a bright light and it startles them there'll crow; if another rooster starts crowing nearby they'll crow. There isn't really anyway to shut them up. But at least you know. 

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