Our hen had to go stay at our in-laws for a couple weeks while we were selling our home. While she was there, she started having very runny, black poops that collect and build up in her downy feathers. I thought it may have just been change of environment/diet. We did an Epsom soak, got her all cleaned up, but she continues to have the black runny poop and it keeps building up in her feathers. Her actual vent area looks clean, but I am a newbie and know nothing! Her behaviour seems normal, she continues to scratch and eat and explore and have dust baths in the garden daily. Should I be concerned? I don’t have oyster shells for her, I’m going to track some down. Just wondering if the black poop is cause for concern and how to fix it! Thanks so much!