I am new to chicken raising and hope someone can help me. I have five 8 week old Isa Browns, which I bought as week old chicks. They are meant to be girls, but the breeder said they can't always be 100% right. I've noticed their 'voices' changing over the past couple of weeks - the 'cheeping' seems to be getting lower in tone, and of course there is the noisier squabbles over food. They are still inside - in multiple packing boxes joined together, while we finish off the coop. This morning, while they were still covered up, one of them made a noise like a football siren/horn. Would this be the start of crowing, or can the girls also make such noises?