Jess (falconry) chase something it shouldn't, and less to keep the bird from getting away, as falconry birds are routinely (and as part of the sport) set free—the bond between bird and falconer serves as a much better leash than any leather or rope ever will; however, it is not always desirable that a bird be able to take flight at its own whim, and both on the glove and on the perch, jesses help ensure this. During hunting season (small game season for North American falconers), jesses are generally worn all season in the mews, and are often removed for the
The Sibley Guide to Bird Life & Behavior The Sibley Guide to Bird Life & Behavior The Sibley Guide to Bird Life & Behavior is a book by David Allen Sibley that shows readers "how birds live and what they do." It is different from most field-identification guides that birdwatchers carry around; rather than help identify birds, it helps watchers gain a deeper understanding of the birds they have already identified. Instead of concentrating on individual species, the book summarizes information for families of birds, presenting "broad patterns" to help readers interpret what they see. The guide includes nearly 800 of Sibley's paintings. The book was first published