1 broody hen and the other 2 stopped laying

[ickinom2]

I have a flock of 29 - 2 roos, 3 bantam ameraucanas, the rest ISA brown. My ameraucanas were laying great after the winter (all of March) and then last week I got 12 new ISA's and all of a sudden the 3 stopped laying (been 9 days no blue eggs) and 1 is broody. I keep kicking her out of the nest and taking the brown eggs she is sitting on but she finds new ones everyday, and no blue eggs. They are just a year old now. I am getting 12 - 16 brown eggs from the ISA's (4mths -18mths old). Any ideas why this is happening?

 

[aart]

Adding new birds can cause stress, which can cause cessation of lay.
Ameraucanas can be sporadic layers anyway....ISA's are usually laying machines.