Aggressive chicks

[anperrin]

We bought 10 Araucana chicks two weeks ago that are now 6-7 weeks old, The two biggest ones seem to be very aggressive, They keep jumping on and biting the necks of the other chicks. Is this normal and if not what should I do to stop them?

 

[sumi]

Jumping and biting the necks of the others? They are still very young, but this sounds like mating behaviour to me. They may be roosters. Post some nice clear head and body pics of the 2 in this section:

https://www.backyardchickens.com/f/15/what-breed-or-gender-is-this

Oh and