Thanks for the suggestions. I was pretty baffled by the loss of the first flock...after my parents helped us raise six day-old chicks up to be healthy young chickens....bitties? We woke up one Sunday morning and my told me that I may want to go outside and check on the chickens b/c she detected no movement. I believed our coop and run to be secure from predators, and I made the mistake of leaving a door open that gives the chickens access o the run from the coop overnight. I expected that we'd lose one or two to predators, due to the variety of carnivores that live here, including cougars, which the authorities will adamantly deny, despite numerous sightings and even one dead carcass found in a roadside ditch after being struck by car. I had prepared the family for that possibility. I wasn't prepared for losing all six in one night. I found a pile of feathers outside the run and a few feathers scattered around the pasture (we also have horses). No trace of any other remains. I thought that some survivors may have gotten out of the run somehow, and ran into the woods, but I never found any. After reading in the learning center and looking at the information on predators, I think the most likely culprit was a raccoon. Due to the fact that all six disappeared the same night, even though I never fund any other evidence (such as heads or disemboweled corpses). I have worked on the run and coop a lot to increase security, and I am much more diligent about shutting our two new adult RIR's up in the coop at night.