The pigeon keepers of New York have been in the spotlight recently, and now a new JL Aronson documentary, Up on the Roof, looks at the gentrification of Williamsburg through their experiences.Up on the Roof follows several devoted pigeon breeders in one predominantly Latino section of Brooklyn through the rigors and rewards of a quintessential New York tradition. All along the waterfront, and throughout blue collar Brooklyn, pigeon fancying has been an active pastime for......