This evening I sat in one of my three larger pens waiting on the owl to come in so I could spy first hand on it. A chair was placed in the coop near about 18 birds roosting in two locations with one group very close to my head and at the same level. We hung out together for a good 90 minutes. Then I periodically could smell something that was not so good. They were farting. Not all at same time, but they definitely were farting without production of feces.