Pigeons and Doves

The smallest species of pigeon is the diamond dove (Geopelia cuneata), only 2 in (15 cm) long and weighing 1 oz (30 g). The largest species is the Victoria crowned pigeon (Goura victoria), 32 in (80 cm) long and 5 lb (2.4 kg) in weight.

Most pigeons are strong fliers, and some species are capable of undertaking long-distance movements and migrations. Other pigeons, especially those living in moist tropical forest, are local birds that spend a great deal of time walking on the ground, foraging for their food of fruits. The pheasant pigeon (Otidiphaps nobilis) of New Guinea is almost entirely terrestrial, and rather fowl-like in its appearance and behavior.

Pigeons are almost entirely seed and fruit eaters. Pigeons have a large, muscular gizzard, which is useful in grinding hard fruits, for example tree "mast" such as acorns, hazelnuts, chestnuts, and other nutritious fruits that most birds are not capable of digesting.

Pigeons have the ability to suck water when drinking. This is rather distinctive, because almost all other birds can only swallow water by taking some into their mouth, and then tilting their head back to let the liquid run down their throat.

Pigeons are monogamous, laying one to two eggs on a rough platform nest, commonly built of twigs. Both sexes share the incubation of the eggs, the male during the day, and the female at night. Young pigeons are initially fed by a material known as "pigeon milk," which is a rich, nutritious secretion of the lining of the crop of the adult birds. This material is collected from the crop by the young birds, which must insert their head rather deeply into the adult's throat to do so. Older chicks are also fed regurgitated seeds and other plant foods.