Pigeons and Doves: Columbidae

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PIGEONS AND DOVES: Columbidae

ROCK PIGEON (Columba livia): SPECIES ACCOUNTS
AMERICAN MOURNING DOVE (Zenaida macroura): SPECIES ACCOUNTS
LUZON BLEEDING HEART (Gallicolumba luzonica): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Pigeons and doves vary in size from 5.9 to 31.5 inches (15 to 120 centimeters) in length and from 1.1 to 4.4 pounds (0.5 to 2 kilograms) in weight. They have compact bodies, short necks, and small heads. The wings are long and broad and the tail is long and either broad or pointed. The bill is short. The eyes are surrounded by an area of bare skin. Males and females are usually similarly colored, although males are often somewhat larger in size. Many species are gray, brown, or cream in color although some tropical species are much brighter.

GEOGRAPHIC RANGE

Pigeons and doves are found worldwide except in the Arctic and Antarctica. There are particularly large numbers of species in Asia, especially Southeast Asia, including on the many islands in that part of the world.

HABITAT

Pigeons and doves occupy a wide variety of habitat types, including desert, grassland, and forest. The largest number of species is found in forested areas, particularly rainforest. Most pigeons and doves are arboreal, which means they live in trees. This includes most species that occupy grassland areas. Rainforest species may be arboreal or terrestrial, ground-dwelling. Some European and Asian pigeons nest in mountainous cliffs at high altitudes. Desert species are found in California and Australia.

DIET

Some pigeons and doves, including tropical fruit doves, are exclusively frugivorous, fruit-eating. Most species swallow fruit whole. After the flesh of the fruit is digested in the stomach, the pit is regurgitated, vomited from the stomach. Other pigeons and doves are granivorous, eating primarily grains and seeds. Seeds are typically picked from the surface of the ground or stripped from the stems of grasses. One species, the Galápagos dove, is known to use its curved bill to dig for hard seeds in the ground. Granivorous doves and pigeons may also eat leaves, stems, buds, and flowers when seeds are unavailable. A few pigeon and dove species eat primarily animal matter. This includes the atoll fruit dove of the Toamotu archipelago in the Pacific Ocean, which eats insects and small vertebrates, animals with backbones, such as lizards, and the Wonga pigeon of Australia, which eats insects and other invertebrates, animals without backbones. Pigeons and doves are also able to drink water by putting their bills underwater and sucking, an ability that is unusual in birds.

BEHAVIOR AND REPRODUCTION

Many species of pigeons and doves form large or small flocks for feeding and other activities. Within flocks, there are dominant and subordinate individuals. The dominant birds, which tend to be larger in size, are usually found in the center of flocks. The smaller, subordinate birds are closer to the edge.

CONSEQUENCES OF AN ALL-FRUIT DIET

Fruit doves eat only fruit. This is an unusual diet among pigeons and doves, and among birds in general, because fruit contains very little protein compared to seeds and insects. Because of their low-protein diet, fruit doves lay only one egg at a time, rather than two like most other pigeons and doves. Also, fruit doves feed their chicks crop milk throughout the nestling period. In other pigeons and doves, adults feed young crop milk for a few days and then gradually replace it with other foods.

Most species of pigeons and doves are monogamous (muh-NAH-guh-mus), a single male breeds with a single female during the breeding season. Courtship, behaviors that lead to mating, in many species involve flight displays. For example, male wood pigeons fly several feet upwards, clap their wings nine times, and then glide. Flight displays are not found in forest or terrestrial species, however. In most pigeons and doves, males perform a "bow-coo" display involving cooing and bowing just before mating. Each pigeon and dove species has a unique "bow-coo" display.

Pigeons build a simple nest of sticks, straw, and other material. The male collects nesting material and passes it to the female, who tucks it around her body. Pairs are territorial and defend their nesting areas from other members of the species. In fights over territory, individuals peck at each other's heads, particularly at the skin around the eye, and beat their wings. In most species, the female lays two eggs at a time. In a few species, only one egg is laid. In many species, both parents share incubation duties, with males incubating, sitting on the nest, from morning to afternoon, and females incubating from the afternoon to the next morning. Eggs hatch after eleven to thirty days. The young are altricial (al-TRISH-uhl), they hatch at an early developmental stage, blind and with few or no feathers. For the first few days, pigeons and doves feed their young crop milk, a fatty substance produced in the crop organs, located in the throat. Both parents produce crop milk. Chicks are able to leave the nest between seven and twenty-eight days after hatching.

PIGEONS, DOVES, AND PEOPLE

Humans have hunted and raised pigeons for food, as pets, and even to transport written messages.

CONSERVATION STATUS

A third of the 316 existing pigeon and dove species are believed to be Threatened by the World Conservation Union (IUCN). Many of these species occupy small oceanic islands and have very limited ranges. The passenger pigeon, once found in North America in flocks of millions, was driven to extinction by human hunting.

ROCK PIGEON (Columba livia): SPECIES ACCOUNTS

Physical characteristics: Rock pigeons are blue-gray in color, with short tails and long, strong wings.

Geographic range: Rock pigeons are found worldwide.

Habitat: Rock pigeons breed in cliff areas or on human buildings. They occupy diverse areas including deserts and grasslands, as well as urban settings.

Diet: Rock pigeons eat grains and seeds.

Behavior and reproduction: Rock pigeons are strong fliers. They generally begin to roost before the sun goes down and wake at dawn. Rock pigeons do not sleep in trees but use a wide variety of crevices, including spaces under rooftops. Rock pigeons are extremely curious birds who investigate their surroundings carefully.

Courtship in rock pigeons involves both partners using their bills to preen, or smooth, their back feathers. Females may stick their bills in the male's bill during courtship, the way young pigeons do when they feed. Both partners then preen each other's heads and necks. The female lays two eggs at a time. Chicks hatch after seventeen or eighteen days. Young are fed crop milk and, later, seeds. Chicks are able to fly after four to five weeks.

Rock pigeons and people: The rock pigeon has been domesticated, tamed, several times, in several different places, by humans. The first domestication may have occurred as long as 10,000 years ago. Rock pigeons have been trained to carry messages. In urban settings, they may be a health hazard to humans since many pigeons carry disease and parasites such as mites and ticks.

Conservation status: Interbreeding with domesticated rock pigeons that have returned to the wild threatens the species, because their young then carry genes from the domesticated varieties, which are usually bred by humans. ∎

AMERICAN MOURNING DOVE (Zenaida macroura): SPECIES ACCOUNTS

Physical characteristics: American mourning doves have olive-gray backs and brownish gray bellies. Their necks are an iridescent pink and purple.

Geographic range: American mourning doves are found in North America and Central America.

Habitat: American mourning doves are found in grassland areas, in hot, dry areas, and sometimes on agricultural lands.

Diet: American mourning doves eat primarily seeds.

Behavior and reproduction: In American mourning doves, males court females by standing behind them and cooing. Males also inflate their crop, showing off the colors of their throat. Males do not bow. At the nest site, males continue to call while spreading their tails in order to show off their white feather tips.

American mourning doves and people: American mourning doves are hunted for sport and food in the United States and Mexico.

Conservation status: American mourning doves are not threatened. ∎

LUZON BLEEDING HEART (Gallicolumba luzonica): SPECIES ACCOUNTS

Physical characteristics: Luzon bleeding hearts have blue gray backs and white bellies. There is a bright, red-orange spot on the breast which gives this species its name.

Geographic range: Luzon bleeding hearts are found in the Philippines.

Habitat: Luzon bleeding hearts inhabit Philippine rainforest areas.

Diet: Luzon bleeding hearts eat seeds, berries, and invertebrates. This species feeds on the forest floor.

Behavior and reproduction: The Luzon bleeding heart male starts the courtship by chasing the female across the forest floor. Males then stop, raise their tails, puff their feathers, lower their heads, and arch their wings. Then they throw back their heads and stick out their breast to show off the bright red breast spot. Males then bow and coo. Little else is known about Luzon bleeding heart reproductive biology and behavior.

Luzon bleeding heart and people: No significant interaction between Luzon bleeding hearts and humans is known.

Conservation status: Luzon bleeding hearts are not threatened. ∎

FOR MORE INFORMATION

Books:

del Hoyo, J., A. Elliott, and J. Sargatal, eds. Handbook of the Birds of the World. Vol. 4, Sandgrouse to Cuckoos. Barcelona: Lynx Edicions, 1997.

Gibbs, D., E. Barnes, and J. Cox. Pigeons and Doves. A Guide to the Pigeons and Doves of the World. Sussex, U.K.: Pica Press, 2001.

Perrins, Christopher, ed. Firefly Encyclopedia of Birds. Buffalo, NY: Firefly Books, 2003.