Telling the gender of my baby chicks

[eshez]

We have black copper marans

 

[NatJ]

We have black copper marans

In that case, any black chick with a light dot on the head must be a male.
Black chicks with no dot on the head may be male or female, depending on their mother. (Mothers with white barring will produce sons with head dots and daughters without. Mothers without white barring will produce sons & daughters with no head dots. This goes for black chicks and would also work for blue chicks, but generally not for chicks of other colors.)