The domestic pigeon normally reaches sexual maturity at about five to six months of age. Depending on the local temperatures and food supply, they may breed all year round. Many fanciers, however, prevent them from breeding continuously -- either by separating the sexes, or by letting mated pairs sit on wooden (dummy) eggs.
Once mated, the male (cock) will begin to hunt for a suitable place to make a nest and rear young. Domestic pigeons do not nest in trees as do many other doves. They are descendants of a cliff dwelling species and prefer their nest to be on a solid surface. Most fanciers (breeders) also provide a nest bowl and some nesting materials (pine needles, tobacco stems, etc.) for the birds to use. The nest bowl helps to ensure that the eggs do not roll out from under the pair and chill.
Both male and female take part in the incubation and rearing of the young. Females lay their first egg about 10 days after mating, usually in the late afternoon or early evening. A second egg is laid about 44 hours later. Two eggs is the normal clutch size. Incubation commences with the laying of the second egg. The male (cock) bird usually broods from about 10 a.m. until 5 p.m., the female (hen) the rest of the time. Hatching normally occurs 18 days from start of incubation. Youngsters are fed by both parents -- and here is where pigeons/doves are unique. The parents need not even leave the nest to hunt down insects, etc., as do many other genera or species. Instead, they feed their young on a glandular crop secretion called "pigeon milk". It is not actually milk, and there is no lactose in it, but its production is stimulated by prolactin, the same hormone which stimulates milk production in mammals. Pigeon milk looks more like a cream-colored cottage cheese and is a high protein food which is fed to the youngsters from hatching till about ten days old when regurgitated grain and grit replace it as the major food source. Domestic pigeons usually have a seamless aluminum identity band placed on their leg at about ten days of age. This band is coded with year of hatch, club identification and a number. Youngsters fledge at about 35 days. However, when the young are about eighteen days old, the parents will often commence to renest. It is not uncommon for one round of youngsters to be fledging at the same time that next are hatching.