Pigeons: The Generalists

When I was a student in Boston, I wondered why I'd never seen a baby pigeon. I'd see other baby birds and nests, but I'd never see anything to suggest the origins of the pigeon. They seemed to spring, fully formed, from the concrete of the city. Where did they come from? And why were they everywhere?
Pigeons have been bred and raised by humans for hundreds of years. We've used them for food, to carry our messages and to provide racing sport. The pigeons in our U.S cities were called "rock doves" and were brought here by early settlers. They are clean, intelligent, hardy and adaptable.
The reason you don't see pigeon nests, or baby pigeons, is because pigeons are doting and protective parents. Pigeons mate for life and both take part in building the nest. Once a safe and secretive place is chosen, the male will bring one twig at a time to the female. She will decide if and how to use it in the nest. The female lays two eggs and both male and female will incubate them. When the young hatch, both parents will feed them. If the first nest is successful, a second nest will be built and a second pair of eggs laid, even before the first pair of hatchlings are fledged. Pigeons will mate all year long and can produce 5 to 6 broods a year. They are cooperative among their kind and will feed chicks who aren't their own.

You've actually got to hand it to the pigeon. Not only can they tolerate the conditions of a city, but they can thrive there. There are 1,000s of ledges and overpasses on and under which to build their nests. Humans provide more than enough food, consciously or, through garbage, unconsciously. The dense population of people discourages predators. It's a fact; pigeons have found an ecological niche few other animals can fit into.