4 week old coturnix crowing and breeding behavior already?

[Fireclaw]

I have 12 4 week olds (they'll be 5 weeks on Friday), I've got at least 3 crowers already (two that I know of, but they only do it when I'm not looking lmao) and today one of the crowers was trying mount another of their cage mates.

How soon can you sex them? I've been told no earlier than 6 weeks to get 100% positive with vent sexing but I've also been told they can start LAYING as early as 6 weeks lol.

 

[Nabiki]

If they're feather sexable, you can tell as early as three weeks. If they're already crowing (and yes, sometimes they start early), then you can identify those males, at least.

The earliest I've had a hen start laying was 5.5 weeks, the latest about 12 weeks.

If you post pictures of their breasts, we can help you if they're feather sexable.

 

[Fireclaw]

If they're feather sexable, you can tell as early as three weeks. If they're already crowing (and yes, sometimes they start early), then you can identify those males, at least.

The earliest I've had a hen start laying was 5.5 weeks, the latest about 12 weeks.

If you post pictures of their breasts, we can help you if they're feather sexable.

They're Tibetan tuxedo and a couple english whites, so no feather sexing unfortunately.

My initial plan with the 12 was to keep a group of 4 or 5 (1 male and the rest females) and sell the rest but the more I think of it, If I can, it'd be more beneficial to keep two breeding groups.