Super cute chicks. I'm not sure about the feathers, but I'd guess they are dirty as opposed to pecked...but you might want to move the chicks to a bigger brooder now. With more space, the chances of pecking each other will be greatly reduced.
wow so cute, could just scoop them all up a tuck them in my shirt
don't know what that is, a cowlick? watch them closely, you may have to isolate that one- s it newhatch, could just be some wet/ blood skin looks intact, dry im off and fluff im up
What gorgeous chicks!! And to answer your question, looks like just dirty feathers to me. You may want to keep some blood stop pwd. or pwd. sulfur on hand in case they do start picking. Chicks can recover from some truly hideous pick wounds, if you get to them & isolate them. Hopefully you won't have to.