It sounds like your going to have to clean it off when you get a chance. The chicks poop everywhere! I clean the coop with a litter box scoop every time I walk in there. I visit them every few hours.lol. So far I let the rain wash out the run. I have to figure out a better plan when it doesn't rain as often. I tried scooping the poo out of the run, but it didn't work. Winter will be tough here, I'm closing off the run and keeping them in the coop when it's snowed in. I'm sure it will be super messy in there and I won't be out there as often with subzero temps.lol