I just found my second dead hen. She's young, looks healthy. No sign of being pecked or hurt by a predator. Some poop around the vent, but it wasn't blocked. No sign of being egg-bound, or maggots, or mites. Their poop is normal, as far as I can tell, maybe a little on the goopy side but then they eat a lot of greens. Some have been molting heavily, others haven't; her feathers looked good and it doesn't look like she was molting. It's not that cold, by chicken standards - going down to around 27F at night - and anyway they have a coop that's got a thick layer of straw on the floor. The coop hasn't yet been closed up for winter; it faces away from the prevailing wind but is still pretty "airy". In winter I nail a cover over the 2X3 window (which is covered with mesh), leaving a gap across the top for air flow. They have free access to layer pellets, oyster shell, grit, and a veggie garden where I don't use any toxins. They also have free access to well water, and we put about a cup of apple cider vinegar in the 5 gal waterer, which is emptied and rinsed each time it's refilled. We give them kitchen scraps daily - not a lot, just whatever we happen to have. I have 18 (now 17) hens and a very sweet roo. A couple are older, but most are gold sex-links, 6 or 18 months old (I'm not sure of the age of this hen). They're producing about 8-10 eggs a day ... Usually we put a light in the coop around now, to give them 14 hours of light per day, but I like to give them a rest before we do that and since they're still laying quite well I haven't yet done so. We found her this morning lying in the veggie garden. I found the last one about a month ago under the coop. (We've raised the coop about 15 inches off the ground to create an area where they can putter around and scratch during snowy or rainy weather - plus for extra shade in summer if they want it.) This is the second apparently healthy hen to drop dead for no clear reason and with no warning that I could recognize. I'm a bit freaked out about it, naturally! Three possible areas of concern: 1. I have rhubarb plants in the veggie garden. Once before I had a hen die of suspected rhubarb poisoning. Nobody else had eaten any so I figured she was an anomaly. In her case, however, she was pretty sick for a while, her crop filled with fluid that then sort of vomited out. In the end I euthanized her because it was clear she was dying. These hens didn't appear to be sick. Apparently there are signs of chickens having nibbled on the rhubarb, so we're now going to take it out, in case that's the issue. 2. I have horseradish plants. I've never seen the chickens show any interest in them, and don't even know if they'd be toxic to chickens. 3. Something I changed this year: I have an area in my chicken run where I've started dumping compost, after viewing several YouTube videos about the benefits of letting chickens and compost work together. (The idea is, the compost gives the chickens something to do, especially in winter and during the growing season when they don't have access to the veggies. They get to scratch around and eat bugs and worms, and the compost gets scratched up and pooped on, and the gardener gets help with turning the compost. Sounds like a win win, and some YouTubers have even found that their chickens eat less of the commercial food while continuing to lay excellent eggs.) The chickens LOVE their compost pile and spend a fair amount of time there. I don't think we've put anything but vegetable garden waste in the compost. Please, does anyone have any suggestions?