Even in a city famed for its oddities, New York's Wild Bird Fund is an unusual place. To wit: one morning in April, while sitting in their Upper West Side waiting room, it dawned on me that I wasn't alone. Perched on a chair, motionless in front of a life-sized photograph of a turkey vulture, was a large black-and-white guinea fowl.

The turkey vulture had been nicknamed Stanley. The guinea fowl, who'd been let out to stretch her wings, didn't yet have a name. Both were among the roughly 10,000 feathered patients—snowy egrets and starlings, peregrine falcons and pigeons—delivered to the Wild Bird Fund since its founding in 2001.

"Any animal that's picked up is in really bad shape," said Rita McMahon, the Wild Bird Fund's founder. "Half the animals brought in for rehab die, or are euthanized. But the other half go free. And they probably would have died if they hadn't come here."

McMahon founded the Wild Bird Fund after rescuing an injured Canada goose alongside Interstate 684 and learning there was nowhere in the city to take him. New York is full of veterinarians, of course, but none wanted to deal with wild animals. At first she ran the operation from her apartment. "I didn't have any idea," she said. "I just started doing it."

Wild Bird Fund founder Rita McMahon with Ben, a tame one-eyed cardinal. Brandon Keim/WIRED

It was a far cry from the current facilities, through which she gave me a tour. On the first floor is an intake room for initial observations, a quarantine chamber for contagious birds, a microscope and an X-ray machine, a wading pool for waterfowl. Downstairs you'll find the operating room and cages for the patients.

Recent patients included a Virginia rail and a woodcock. For now, aside from a yellow-bellied sapsucker and dark-eyed junco in intensive care, both victims of window collisions, it was mostly pigeons. Medical care for lowly pigeons might seem a bit much, but it was hard to begrudge after hearing their tales.

McMahon pointed me to a climate-controlled cubicle containing two nestlings, the only survivors of a brood of 13 that had been packed into a FedEx box. "A guy thought it was a good joke to send them to his girlfriend," she explained. "They were there in the box for two days with no water, no food, and freezing. They all looked dead. When we heated them up and gave them fluids, these two made it. The girlfriend broke up with him."

Upstairs it was time for the waterfowl to take their daily swim in the wave pool. Without it, their feathers lose their natural waterproofing, and their feet dry out and become infected. Sometimes a loon comes through; they're allowed to dive for goldfish. Mute swans are frequent guests. The males are renowned for their antagonism towards men, and only accept care from the hospital's women helpers.

On this day the waterfowl included two Canada geese, three herring gulls and a mallard. Under the care of volunteer Esther Koslow they took their laps, then gathered in the waiting room, preening quietly.

Downstairs it was rather less peaceful. After feeding, while their cages were cleaned, several pigeons stayed out for exercise. Assisting were several students from the LaGuardia Veterinary Technology Program, none of them especially good at catching pigeons. Mild pandemonium ensued.

"No badminton!" McMahon shouted, referring to one of the trainees' pigeon-catching attempts. "Talk to the bird. 'Hello, you beautiful thing,'" she cooed, plucking one from mid-air. With Derek Jeter-like aplomb, she snagged another with her other hand, then returned both to their cages.

A pigeon nestling. Brandon Keim/WIRED

Rita wasn't annoyed. After all, it's a small army volunteers who make it possible to accept, free of charge, every bird that comes through the door. More than 200 people help, most having learned of Wild Bird Fund after finding an injured bird themselves.

The volunteers span all walks of city society. Homeless people distribute flyers. Antique dealer Stephanie Rinza, part-owner of the Vanderbilt mansion, recently let the Wild Bird Fund use it for a fund-raiser. At the party, said Koslow, a one-eyed male cardinal fell head-over-tailfeathers for Sigourney Weaver. She wore an dull orange dress and may have resembled a large female cardinal.

With the pigeons cooped, several larger fowl roamed the floor: the guinea hen, a large red rooster and a chukar, a small gamebird that is the national bird of Pakistan. It was found in Queens. They'd all most likely escaped from live poultry markets. Different as they looked from one another—the chukar barely reached the rooster's knees—they're members of the galliform order, and instinctively clustered together.

"Chickens, chukars, guinea hens—these are not part of our mission, but we take them all in," McMahon said. "What else are you going to do?" Wild birds are returned to the wild, but these would probably be sent upstate to a sanctuary run by Zezé, the eponymous founder of Zezé Flowers, one of the city's best-known florists.

When wild birds need extra time to recuperate, said McMahon, they go to the Raptor Trust in New Jersey. Raptors are regularly brought in, including a female red-tailed hawk that had stepped in tar and calmly allowed a volunteer to scrub it from her talons. "As soon as we put her in a cage, she was ferocious," recalled McMahon. "But while we cleaned her, she didn't even stir. It was like the story of the lion with a thorn in his paw. She knew what we were doing."

As the day progressed, a worker from the city's Department of Parks & Recreation arrived with an escaped lovebird. A young man dropped off a pigeon found immobile on his apartment building's roof. Eugene Oda, another volunteer, looked it over. The prognosis wasn't good. Much of their work, said Rita, is simply providing birds with comfort in their final hours: food, water, sedatives. It's avian hospice care.

Oda went to the operating room to re-splint a pigeon's leg. The splint was made from a paper clip and wrapped in medical tape. Later in the afternoon a woman came in with a starling she found on 73rd street, on her way to a Passover dinner. The starling flapped feebly. A bad sign, Oda said, but he still had a chance to live.

"It was just dying on the side of the road," the woman said tearfully. She stroked the starling's feathers and whispered soothingly. "I don't know why I'm so upset, but I am," she said. "I'm not even a bird person."