Hello, I'm a new backyard chicken farmer in So. Cal. my flock was made up of 3 Rhode Island Reds and 3 Americanas all except one Americana are laying. Last month one of my Reds suddenly couldn't move. She had all the signs of being egg bound, after trying all the recommended procedures she lost her battle and died. My flock seemed to be doing very well, I feed them a balanced diet of organic feed, oyster shell and all the vegetables and fruit I give them is also organic. As in so many other cases that I've read about, my flock seemed perfectly normal yesterday. This morning I found my Red dead under the perch. I'm not only sad, I'm very confused and worried that I'm doing something wrong. They are free to roam in our yard every afternoon, we've never sprayed any type of pesticide, but if they were to ingest a black widow or any other type of poisonous spider could that cause death? I've heard of the West Nile infecting local birds, could it be possible that it could infect my flock too? Also, is it okay to add new hens to my flock to replace the two that I've lost or would that upset the balance? Would I even be able to find hens of the same age? Thank you for any information, wisdom or sympathy.