The Elusive City Squab

Q. Pigeons are everywhere, but has anyone ever seen a baby pigeon?

A. No. They are mythical creatures born in adult form, like the Greek goddess Athena when she sprang from the head of Zeus.

Just kidding, of course: Pigeons are secretive birds, and as such like to build their nests in hidden locations. What’s more, it takes only a month for a chick — properly called a squab, informally known as a squeaker — to become fully developed and leave the nest, limiting the time you have to come across one.

The feral pigeons that inhabit the city today are the descendants of wild rock pigeons, also known as rock doves, which are native to Europe, northern Africa and southwestern Asia.

Wild pigeons build their nests in places unlikely to be disturbed by other animals, such as on cliff faces. Window ledges, rooftops and scaffolding serve as stand-ins for their cosmopolitan relatives.

When a male pigeon looks for a mate, he finds a good nesting spot before launching into his mating call. If he is successful, the female remains at the site while the male brings twigs and other materials to build the nest.

Both parents take turns incubating the eggs, which typically come in pairs and take 16 to 19 days to hatch. The chicks are born helpless, covered with yellowish-brown fuzz; nourishment comes from a white substance called “pigeon milk,” which their parents regurgitate into their mouths.

One New Yorker who has seen her share of squabs is Rita McMahon, co-founder and director of the Wild Bird Fund, a nonprofit that rehabilitates wildlife of all kinds.

On a recent afternoon, several large birds roamed freely around the organization’s Upper West Side headquarters, including a juvenile swan named Warrior who had found himself frozen in ice in Prospect Park. (“They’re just young and stupid,” Ms. McMahon said. “They don’t know winter yet.”)

There were no baby pigeons, however. Ms. McMahon estimated that squabs account for one-sixth of the 6,000 birds her team treats each year. The flow is fairly consistent, as pigeons, which have an expected life span of two to three years, mate year-round.

Many patients arrive with broken legs. That’s because squabs nearing maturity go through an angst-filled teenage phase, which can result in a desire to leave the nest prematurely.

“If they come out too early and they don’t have the wings, all the flapping in the world isn’t going to keep them from hitting hard,” Ms. McMahon said.

This risky period requires the parents to navigate between protecting the squabs from harming themselves and letting them go free. If their young become overly dependent, for example, they could have a difficult time making it on their own.

Human guardians can be faced with the same challenge, as one Metro reporter for The New York Times discovered last year when he raised a pair of baby pigeons in his bathroom.

“You get very attached to them,” Ms. McMahon said. “They are charming.”