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Reproduction
Domestic pigeons reproduce in a similar way to the wild rock pigeon. Generally humans will select breeding partners. Crop milk produced by parent birds may occasionally be replaced with artificial substitutes. Baby pigeons are called squeakers or squabs.[7]
See also: Rock pigeon § Stages of life cycle
Homing pigeons
Main articles: Homing pigeon and Racing Homer
Group of pigeons
The ability a pigeon has to return home from a strange location necessitates two sorts of information. The first, called "map sense" is their geographic location. The second, "compass sense" is the bearing they need to fly from their new location in order to reach their home. Both of these senses, however, respond to a number of different cues in different situations. The most popular conception of how pigeons are able to do this is that they are able to sense the Earth's magnetic field[8][9][10] with tiny magnetic tissues in their head (magnetoception)[citation needed]. This is all the more surprising as they are not a migratory species, which is a fact used by some ornithologists to dispute this theory[citation needed]. Another theory is that pigeons have compass sense, which uses the position of the sun, along with an internal clock, to work out direction. However, studies have shown that if magnetic disruption or clock changes disrupt these senses, the pigeon can still manage to get home. The variability in the effects of manipulations to these sense of the pigeons indicates that there is more than one cue on which navigation is based and that map sense appears to rely on a comparison of available cues[11]
Other potential cues used include:
- The use of a sun compass[12]
- Nocturnal navigate by stars[13]
- Visual landmark map[14][15]
- Navigation by infrasound map[16]
- Polarised light compass[17]
- Olfactory stimuli[18]
Other purposes of pigeon breeding
For food
Main article: Squab (food)
Pigeons are also bred for meat, generally called squab and harvested
from young birds. Pigeons grow to a very large size in the nest before
they are fledged
and able to fly, and in this stage of their development (when they are
called squabs) they are prized as food. For commercial meat production a
breed of large white pigeon, named "King pigeon," has been developed by selective breeding. Breeds of pigeons developed for their meat are collectively known as utility pigeons.Exhibition breeds
Main article: Fancy pigeon
Pigeon fanciers developed many exotic forms of pigeon. These are generally classed as fancy pigeons. The Fanciers compete against each other at exhibitions or shows and the different forms or breeds are judged to a standard to decide who has the best bird. Among those breeds are the English carrier pigeons, a variety of pigeon with wattles and a unique, almost vertical, stance (pictures).
There are many ornamental breeds of pigeons, including the "Duchess"
breed, which has as a prominent characteristic feet that are completely
covered by a sort of fan of feathers. The fantail pigeons are also very ornamental with their fan-shaped tail feathers.Flying/Sporting
Domestic pigeons in flight
Main article: Flying/Sporting pigeons
Pigeons are also kept by enthusiasts for the enjoyment of Flying/Sporting competitions. Breeds such as tipplers are flown in endurance contests by their owners.Experimentation
Domestic pigeons are also commonly used in laboratory experiments in biology, medicine and cognitive science.Cognitive science
Pigeons have been trained to distinguish between cubist and impressionist paintings, for instance. In Project Sea Hunt, a US coast guard search and rescue project in the 1970s/1980s, pigeons were shown to be more effective than humans in spotting shipwreck victims at sea.[19] Research in pigeons is widespread, encompassing shape and texture perception, exemplar and prototype memory, category-based and associative concepts, and many more unlisted here (see pigeon intelligence and discrimination abilities of pigeons).Illegal predator killing by enthusiasts
In the United States, some pigeon keepers illegally trap and kill hawks and falcons to protect their pigeons.[20] In American pigeon-related organizations, some enthusiasts have openly shared their experiences of killing hawks and falcons, although this is frowned upon by the majority of fanciers. None of the major clubs condone this practice. It is estimated that almost 1,000 birds of prey have been killed in Oregon and Washington, and that 1,000–2,000 are killed in southern California annually. In June 2007, three Oregon men were indicted with misdemeanour violations of the Migratory Bird Treaty Act for killing birds of prey. Seven Californians and a Texan were also charged in the case.In the West Midlands region of the United Kingdom pigeon fanciers have been blamed for a trap campaign to kill peregrine falcons. Eight illegal spring-loaded traps were found close to peregrine nests and at least one of the protected birds died. The steel traps are thought to have been set as part of a “concerted campaign” to kill as many of the birds as possible in the West Midlands.[21]
Columba livia domestica
Feral pigeons
Main article: Feral pigeon
Feral rock pigeons commonly show a very wide range of plumage variation
By: Golubovi Pigeon Inči
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