I use those cat litter buckets to store the chicken feed in, and another one holds all the cleaning brushes, scoops, dust pans, etc. I also have a special needs SLW with a cross-beak, named Sylvie, whose entire day is about eating. Sylvie knows that "bucket=food," in fact, she knows it so well, that no bucket is safe from her investigation. If I am cleaning out the coop, she is in the cleaning bucket. When I go out to feed them and open the storage cabinet, she's in the cabinet climbing into the feed bucket before I can even bring it out to dispense the feed. So, yes, she fits inside one of those buckets, and she chooses to get into them on her own. In fact, I think the bucket is even deeper than the nesting boxes that the girls use in the coop. I think the buckets would make fine nesting boxes. There are posts on here that show nesting boxes made from 5 gallon paint buckets. I think the cat litter buckets would work even better, since they are flat and won't roll around.
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