In the modest backyard of Rosemarie Morgan's 1890-era house, about a half-mile from Yale University, there is a small Buddha, azalea and forsythia, Japanese cherry and plum trees, and an Amish-made chicken coop with five residents — four who lay eggs and Gloria, who is barren but one heck of a watchdog. The fowl are technically illegal under New Haven's zoning code, which prohibited raising hens and other livestock when it was updated during the 1950s. But these days, many dozens of backyard hens are generally tolerated under the city's informal enforcement program — call it "don't cluck, don't tell" — that mostly looks the other way. With urban fowl increasingly common, Alderman Roland Lemar has introduced legislation that would allow residents to raise up to six hens.