Board Thread:General Discussion/@comment-25030726-20140912150313/@comment-25030726-20141009160434

Actually, the timer activates the moment you put the habitat back into play. It's just not visible and you can put dragons in the habitat. For example, let's say you put a small Light habitat back into play. It has a build time of four hours. When you first put it into play, you can put dragons in it. If you refresh your game after an hour, the remaining build time will be 3 hours and you'll have to wait until that is done to interact with it or its occupants.