Welcome to the BYC flock! We are glad you joined us!
How old are the birds in question? Is it possible that they are just a little slower to start laying, are they molting, is the lack of daylight throwing them off?
I ask the questions above because:
* I do know some breeders who say that their Ameraucanas start laying a little later than some of their other breeds
* A chicken who is molting (losing feathers) is spending all their efforts on growing feathers rather than laying
* Chickens lay best with a minimum of 12-15 hours of daylight.
So, right now, we have about 9 hours of daylight where I live and my chickens are molting. Hence, I am only getting about 1 egg per day out of 11 hens. In fact, come to think of it, I have not gotten a single egg from any of my easter eggers, or Welsummers in over one month. All I am getting right now are brown eggs too.