Saturday 28 July 2012

Fancy Pigeons

"Pigeon" and "Dove" redirect here. For other uses, see Pigeon (disambiguation) and Dove (disambiguation).
For pigeon species familiar to people around the world, see Feral Pigeon, Domestic Pigeon, and Rock Dove.

Geographic range of the Columbidae Family
Pigeons and doves constitute the bird family, Columbidae, that includes some 310 species of near passerines. They are stout-bodied birds with short necks, and have short, slender bills with fleshy ceres. Doves feed on seeds, fruits, and plants. This family occurs worldwide, but the greatest variety is in the Indomalaya and Australasia ecozones.

In general, the terms "dove" and "pigeon" are used somewhat interchangeably. In ornithological practice, "dove" tends to be used for smaller species and "pigeon" for larger ones, but this is in no way consistently applied, and historically, the common names for these birds involve a great deal of variation between the terms. The species most commonly referred to as "pigeon" is the Feral Rock Pigeon, common in many cities.

Doves and pigeons build relatively flimsy nests from sticks and other debris, which may be placed in trees, on ledges, or on the ground, depending on species. They lay one or two eggs, and both parents care for the young, which leave the nest after seven to 28 days.[1] Unlike most birds, both sexes of doves and pigeons produce "crop milk" to feed to their young, secreted by a sloughing of fluid-filled cells from the lining of the crop. Young doves and pigeons are called "squabs".







Pigeons and doves exhibit considerable variations in size. The largest species is the Crowned Pigeon of New Guinea, which is nearly turkey-sized, at a weight of 2-4 kg (4.4-8.8 lb) The smallest is the New World Ground-Dove of the genus Columbina, which is the same size as a House Sparrow and weighs as little as 22 g.[2] With a total length of more than 50 cm (19 in) and weight of almost 1 kg (2 lb), the largest arboreal species is the Marquesan Imperial Pigeon, while the Dwarf Fruit Dove, which may measure as little as 13 cm (5.1 in), has a marginally smaller total length than any other species from this family.[2] Smaller species tend to be known as doves, while larger species as pigeons, but no taxonomic basis distinguishes between the two.[2]

Overall, the Columbidae tend to have short bills and legs, and small heads on large compact bodies. Their characteristic head bobbing was shown to be due to their natural desire to keep their vision constant in a 1978 experiment by B. J. Frost in which they were placed on treadmills - they did not bob their heads as their surroundings were constant.[3] The wings are large and have low wing loadings; pigeons have strong wing muscles (wing muscles comprise 31–44% of their body weight) and are amongst the strongest fliers of all birds. They are also highly maneuverable in flight.



The Common Indian Dove mostly seen in the Villages of India
The plumage of the family is variable. Granivorous species tend to have dull plumage, with a few exceptions, whereas the frugivorous species have brightly coloured plumage.[2] The Ptilinopus fruit doves are some of the brightest coloured pigeons, with the three endemic species of Fiji and the Indian Ocean Alectroenas being amongst the brightest coloured. Pigeons and doves may be sexually monochromatic or dichromatic. In addition to bright colours, pigeons may sport crests or other ornamentation.

Like some other birds, Columbidae have no gall bladders.[4] Some medieval naturalists concluded they have no bile (gall), which in the medieval theory of the four humours explained the allegedly sweet disposition of doves.[5] In fact, however, they do have gall (as Aristotle already realised), which is secreted directly into the gut.[6]




Pigeons and doves are distributed everywhere on Earth, except for the driest areas of the Sahara Desert, Antarctica and its surrounding islands, and the high Arctic. They have colonised most of the world's oceanic islands, reaching eastern Polynesia and the Chatham Islands in the Pacific, Mauritius, the Seychelles and Réunion in the Indian Ocean, and the Azores in the Atlantic Ocean.

The family has adapted to most of the habitats available on the planet. The largest number of species is found in tropical forests and woodlands. These species may be arboreal, terrestrial or semiterrestrial. Various species also inhabit savannas, grasslands, deserts, temperate woodlands and forests, mangrove forests, and even the barren sands and gravels of atolls.



The Zebra Dove has been widely introduced around the world.
Some species have large natural ranges. The Eared Dove ranges across the entirety of South America from Colombia to Tierra Del Fuego, the Eurasian Collared Dove has a massive (if discontinuous) distribution from Britain across Europe, the Middle East, India, Pakistan and China, and the Laughing Dove across most of sub-Saharan Africa, as well as India, Pakistan and the Middle East. Other species have a tiny, restricted distribution; this is most common in island endemics. The Whistling Dove is endemic to the tiny Kadavu Island in Fiji, the Caroline Ground-dove is restricted to two islands, Truk and Pohnpei in the Caroline Islands, and the Grenada Dove is restricted to Grenada in the Caribbean. Some continental species also have tiny distributions; for example, the Black-banded Fruit Dove is restricted to a small area of the Arnhem Land of Australia, the Somali Pigeon is restricted to a tiny area of northern Somalia, and Moreno's Ground Dove is restricted to the area around Salta and Tucuman in northern Argentina.[2]

The largest range of any species is that of the Rock Dove. This species had a large natural distribution from Britain and Ireland to northern Africa, across Europe, Arabia, Central Asia, India, the Himalayas and up into China and Mongolia. The range of the species increased dramatically upon domestication, as the species went feral in cities around the world. The species is currently resident across most of North America, and has established itself in cities and urban areas in South America, sub-Saharan Africa, Southeast Asia, Japan, Australia and New Zealand. The species is not the only pigeon to have increased its range due to the actions of man; several other species have become established outside of their natural range after escaping captivity, and other species have increased their natural ranges due to habitat changes caused by human activity.[2]






















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