I have been losing birds regularly off and on all summer. I think the first batch were because they didn't figure out the new watering system. We went back to the old system and the deaths slowed WAY down. Then we had some meat chicks in with some egg chicks and they were so much bigger, I think they just bullied them to death. We got them split up and eventually put all of them minus the meat chickens into the coop. There was some size difference, but I didn't think enough to be an issue. We would then only lose a couple here and a couple there, and I thought maybe it was the size difference, but we didn't see anything visibly wrong with the chickens. Most of the birds that were dying were the smallest ones. Now I've lost 4 chickens in just a few days, and I have no idea why. 2 of the 4 were the largest ones I have. Now all the birds but one are larger birds. I'm really getting sick of dead chickens, but I have no idea what I'm doing wrong?