Isa Brown, Hens or Roosters?

[LeaB]

I bought 13 chicks at the feed store labeled Isa Brown. If I recall correctly they were all light red and they look very similar to each other now as hens and the eggs are fairly uniform medium to dark brown.

I wanted to hatch my own chicks so I bought an Isa Brown rooster from the hatchery. He was a plain yellow chick and is light colored now.

I hatched 23 eggs last weekend. I expected red and yellow sex-linked chicks and instead got quite a mix. So now I'm at a loss, how do I tell which are roosters? Some of the yellow ones have reddish heads, a few have stripes and there's even a dark one.

Would I be safe assuming the lightest ones at least are roosters or do I need to grow them out?

Thanks,
Lea

 

[JedJackson]

The sex link thing only works in the first cross. You won't get sex links by crossing red sex links together. It's a genetic thing. So you will have to wait until they are 6 weeks old or so, and begin then judging by the usual traits, especially color and size of the combs.