newbie here, but as a guess....worm whoopie?

How long have you had your bin. My euro's tend to be where there is lots of moisture and food. If places in the bin are drier or without much food, not so many worms. your worms may be aok. I dug in my worm bin today and noticed the same thing. I don't think its anything to worry about, as the places I didn't find many worms didn't have much food or moisture available either. I think you will find your euro's will like it a little wetter than ef's. Don't drown them but they do seem to go for the wetter parts of the bin. Just my thoughts. Great question to make me think of what was happening in my bin. steve

I have no experience with Euros so i can't give an opinion on the worms clumping up but i thought i would add my 2cs anyway.

I am concerned about the chicken feed. Members who have used it have reported a slow buildup of salt in their bins. Salt isn't good for the worms or the garden.

I would only use the chicken feed as a treat not the main course.