I have been using straw and cleaning it out daily-oh lordy what a yucky mess-12 geese and 7 ducks make a lot of poop! They are only indoors at night now, a modified dog house with a covered pen attached to it. In the mornings it is just solid wet poop! I had initially used pine shavings with them, but after two days (being cleaned 3 times daily-all new shavings each time) the stench was unbearable. WOuld it have been better if I had just put new on top of the old? I am having SO much fun with my birds-first time I have had any-so I just need to figure out how to make living with them ...not unpleasant!