I have four ducks that are about a year old and they have a large enclosed run, half of which is protected by a roof and half isn't. I have always used pea gravel for their run b/c it's easy to hose down, and I've put straw in their beds and wood shavings in the nest box. I had to take one of my Pekin drakes to the vet on Friday for an eye infection, and the vet noticed he had callouses on his feet and said these were from walking on the pea gravel. She said they could become ulcerated and cause Bumblefoot. It seems like a lot of you use pea gravel for your runs, so I'm curious to hear what others have to say about this. The vet suggested removing the gravel and replacing it with straw or wood shavings, which I imagine would be a nightmare when it gets wet. Any thoughts about this?