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ABSTRACT : The number and variety of organism found within a specified geographic region is called biodiversity. Biodiversity supports a number of natural ecosystem processes & services, such as air quality, climate regulation,water purification, pest & disease control, pollination and preservation of erosion. Birds are priceless part of our heritage. They are economically important & reflect the health of our environment. Over
1,228 species of birds are found in India. Approximately 82 species have been listed as threatened in the IUCN
Red list of threatened animals (IUCN,2006). There are approximately 403 endangered birds in the world today.
This paper deals with the Biodiversity of species of the Columbidae family. There are 318 species of pigeon and dove in the world. Most of the species are grey in colour with pinkish, red, white or black spots on particular part of the body. Practically all parts of the world outside the Polar Regions are inhabited by some kind of pigeon or dove. Today around 59 species of pigeon and dove are categorized as globally threatened with extinction, this is 19% of all species and a further 13% (38) species are near threatened. rapidly and by the late 1880s large flocks, which had 1.INTRODUCTION
Biodiversity means the variety of life on earth and the variability among species and between ecosystems.
Birds are important part of biodiversity and ecosystem. The objective of the paper is to attract once been so common, had become a matter of comment and investigation. The last known specimens were seen in most states of the Eastern
United states in 1890s and in 1900 they died out in students, research scholars and common people towards dove species which are very common. They are important component of agro-ecosystem, used for food, popular game bird, important pollinating agents and are used in experimental research in biology and comparative psychology. Inscriptions found by archeologists to that thousands of years before recorded history some doves and pigeons were considered holy and no other bird group is so frequently referred in the Bible. Because of various reasons some dove species are extinct, endangered, threatened and vulnerable.
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DESCRIPTION OF SOME DOVE SPECIES
Passenger pigeon (Ectopistes migratorius) :- It was blue, long tailed, fast and graceful pigeon and was once probably the most numerous bird on earth.
In the 19 th century, there were between one and four billion p.p up to 40% of the total numbers of birds in
North America. Now they are extinct, the last the wild in Ohio.
2. Socorro dove (Zenaida graysoni): - It is extinct in the wild. It was endemic to Socorro Island in the
Revillagigedo Islands. The last sighting in its natural habitat was in 1972. It is a close relative to the mourning and eared doves, was at one time considered its sub species. It was about 26.5-34cm long and 190 gram in weight. The Socorro dove is thought to have been extirpated mainly by feral cats, but high levels of understory grazing by sheep may have limited the population, human hunting might have temporarily brought down numbers.
3. Pink pigeon (Nesoenas mayeri): The pink pigeon has light pink feathers, dark pink bill, legs and feet with a dark brown tail, about 32cm. long and
350gm. in weight. It is endemic to Mauritius and is survivor of a species died in captivity in 1914.
Reasons of its extinction- the birds fed mainly on acorns, chestnuts and beech nuts in the extensive wood lands of North America, when these were steady cut down their habitat and food supplies were reduced. The Indians captured the pigeons in large nets and by the 1630s the settlers of New England were doing the same. The young squabs were regarded as a great delicacy and the adults were sought after for their feathers as well as their meat.
After 1830 the practice of releasing live pigeons from traps for shooting practice began. Numbers fell now very rare. It was on the brink of extinction in
1991 when only ten individuals were remained. The
IUCN down listed the species from critically endangered to endangered on the IUCN Red list in
2006. Mauritius has a series of stamps depicting the endemic pink pigeon.
4. Negro fruit dove (Ptilinopus arcanus): This species is one of the least known birds in the world. It is endemic to the Philippines. Its natural habitat is sub tropical and tropical moist low land forests. It is threatened by habitat loss. There have been no recorded sightings of it since 1953, it may or may not be extinct.
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Polynesian Ground Dove (Gallicolumba erythroptera): It is endemic to French Polynesia. It
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is threatened by habitat loss. It was formerly caught by local people for food but it is more likely that the introduction of cats and rats, particularly black rat
Rattus rattus, are the real reasons for its decline.
Habitat loss is also likely to have been a factor as the largest atolls with richest vegetation have been cleared for coconut plantation. Since it is unknown whether or not the bird is survived, it is classified as critically endangered.
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Common wood pigeon (Columba palumbus):-
Identified by its larger size at 38-43cm, the white patches on its neck and wing. It is otherwise basically grey birds with pinkish breast .Juvenile do not have the white patches on either side of the neck. In the colder northern and eastern parts of Europe and
Western Asia range of common wood pigeon is migrant ,but in Southern and Western Europe it is a well distributed and often abundant resident.
7. Rock pigeon (Columba livia): -It is 35-37cm long.
It has dark bluish –gray head, neck and chest with glossy yellowish, greenish and reddish-purple iridescence along its neck and wing feather. Natural resident range in Western and Southern Europe,
North Africa and into Southern Asia. It has large global population, including an estimated 17-28 million individuals in Europe, common in cities.
8. Yellow eyed Pigeon (Columba eversmanni): In winter it breeds in north-east Pakistan and Jammu and Kashmir in India. It is a rare winter visitor and passage migrant in India. It is about 30cm long. The above species photographed for the 1 st time in India in October 2009 by Mr.S.S.Punia, the officer incharge of the Tal Chapper Sanctuary (Raj.).
9. Nilgiri wood Pigeon (Columba elphinstonii): It is large pigeon found in the moist deciduous forest and scolas of the Western Ghats and in Nilgiri Hills.
They are large sized, dark coloured and have distinctive checkerboard pattern on their nape. It is
Endemic to Western Ghats currently threatened while not exceedingly.
10.Pale capped pigeon:-(Columba punicea): It is also known as purple wood pigeon .It is about 36-
40.5cm long, they are found patchily distributed in parts of South and South East Asia. Records of the species exist from Maharashtra, Orissa, Bihar,
Andhra Pradesh (Araku valley).they are seasonal visitors in Sri Lanka. Pigeon is all-dark chestnut brown with a contrasting pale crown.
3. SPECIES SPOTTED IN CHURU DISTRICT
1. Indian Ring Dove -(Streptopelia decaocta decacoto
)
2. Red Turtle Dove - (Streptopelia transquebarica)
3. Indian Spotted Dove - (Streptopelia chinesis suratensis)
4. Laughing Dove - (Streptopellia sengalensis cambayensis)
1 .IndianRing Dove(Streptopelia decaocta decacoto
):A pale gray and brown coloured distinguished by a prominent narrow black half colour on hind neck.
Breast lilac passing into ashy grey on abdomen and darker grey on vent and under tail coverts broad white terminal edge to blackish tail conspicuous in flight, essentially when spread white alighting.
2. Indian Red Turtle Dove(Streptopelia transquebarica):A small 23cm ,dainty brightly coloured grey and pinkish bright –red dove .In overall effect a good replica of Ring Dove but smaller and with relatively shorter tail.
3. Indian Spotted Dove (Streptopelia chinesis suratensis): Their length ranges 28-32cm .They are pinkish brown and grey in colour spotted with white and with a conspicuous black and white ‘Chessboard’ at base of hind neck .Tail blackish brown and slate with broad white terminal boarder which flashes prominently when spread out as bird is alighting. The legs are red.
4. Laughing Dove(Streptopellia sengalensis cambayensis):They are long tailed, slim pigeon, typically 25cm in length. A small slim pinkish brown and grey in color head and neck lilac-pink with a miniature ‘chessboard’ in black and refocus on either side of fore neck. Breast is pinkish brown. Tail graduated with much white near tips of the outer feathers .
4. ENVIRONMENTAL CONTAMINANTS
Doves are susceptible to lead ingestion from their utilization of road side grit contaminated with lead from automobile exhausts activity of enzyme necessary in heme-biosynthesis, deltaaminnolevulinic acid dehydrates (d-ALAD) decrease as liver lead concentration increased. Lead poising cause’s loss of weight, weakness, lethargy and in some cases diarrhea, also effect the reproductive potential of doves. A historical study of lead poisoned ringed turtle doves in the laboratory not only showed the typical lesions in the kidney and liver and also showed lesions in the testes and inhibition of spermatogenesis in the seminiferous tubules (kendall et.al 1981).
Organo-chlorine insecticides such as DDT and its metabolites, aldrin, dieldrin, chlordane, benzene hexachloride, heptachloro and toxaphene- were widely used after world war II. However their use has declined rapidly since 1970, having been largely replaced by organophosphates as parathion, malathion, fenthion and diazinon. Polychlorinated biphenyl (PCB) compounds are used in industry but contaminate the environment in the manufacture and disposal process. Organophosphates degrade quickly in nature, but both organochlorides and PCBs are very persistent in the environment, where they can remain for years. They can be stored in the body fat of many animals and undergo biomagnifications through the food chain. Acute poisoning with these chemicals results in neurological signs, carcinogenicity, decrease in reproductive efficiencies and degenerative changes in body organs.
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5. CONCLUSION
Various human activities like counting habitat loss for residential housing, road and other development, excess use of pesticides, over exploitation, over hunting, natural calamities, predators like cats, dogs, raptors, rodents and other birds like hawks, owl etc. are some reasons for decline in population of various dove species. Now it is the time to use ecofriendly products to save the environment from pollution.
6. REFERENCES
1. Buerger,T.T. 1984. Effect of lead shot ingestion on captive mourning dove survivability and reproduction. M.S. Thesis, Auburn Univ.,Auburn,
Alabama.50pp.
2. DeWeese, L.R., L.C. Mc Ewen, G.L. Hensler, and
B.E. Peterson. 1984. Pesticide and PCB contamination in migratory birds of the western
United States. Abstract. Bull. Ecol. Soc. America 65
(2): 235.
3. Gabrielson, I.N. 1941. Wild life conservation. The
Macmillam Co., New York 250pp.
4. Schorger, A.W.1955. Introduction of the domestic pigeon. Auk 69 (4): 462-463-------1955. The passenger pigeon : Its natural history and extinction.
Univ. Wisconsion Prees , Madison. 424pp.
5. Salim Ali and S. Dillon Ripley, Handbook of the
Birds of India and Pakistan, Vol. III, Stone Curlews to Owls 93-162.
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