Chick mounting = Rooster?

[bird_brain_scientist]

Thank you BYC - you have helped me raise my first four beautiful chicks to the ripe old age of 1.5 weeks! I am the proud daddy of an Easter Egger, a Welsummer, a Barred Rock and a RIR

They were delivered by USPS from mypetchicken.com, which promises 90% sexing success. Now, while it is probably too soon to tell, the EE is by far the biggest, pushiest, most alpha chick of the batch - maybe just the top of the pecking order, maybe a couple days older than the others, or maybe... a roo? In spite of being the tough guy he also the only one of the lot who still freaks out when you touch him. I will win it over with yet with my yogurt training!

Here's the latest clue: my girlfriend thinks she saw it mount my poor baby Welsummer! Now, at less than two weeks I presume they're a long way from sexual maturity. Maybe it is just a dominance behaviour?

I am really hoping I don't have any roos as in my urban backyard situation I would have to find it a new home. The EE really single-handedly stirs things up in the brooder, too

 

[bird_brain_scientist]

Here are the babies at 1 day old. I am smitten.

 

[JerseyHen]

I don't know how early roo's start acting differently. We are on our first batch of chicks. We have a dark brhama that started acting more agressive and standing differently (really upright) and initiating chest bumping and who is also restless when you pick up. I suspected roo from about 1.5 weeks as well and I also thought I saw "Leroy" (loretta if I am wrong) mount one of the girls. He grabbed her by the back of the head and tried to jump on. Playing? Dominance? Roo? Same question, so here's a bump!