California ? The California condor, rescued from extinction in an elaborate and expensive recovery effort, has become tantamount to a zoo animal in the wild and can’t survive on its own without a ban on lead ammunition across its vast Western ranges, a scientific study has concluded.

The majestic scavengers, bred in captivity and released to nature in recent decades, require “constant and costly human assistance,” a blue-ribbon panel of the American Ornithologists’ Union reported this week.

They must be trapped frequently, tested and treated for lead poisoning. They depend on man-made “feeding stations,” a buffet of lead-free carcasses of rats, deer, stillborn calves and other animals, a practice that has damaged their ability to forage.