Monday, October 8, 2012
House Sparrows- Miss these little buddies..
They are vanishing from many big cities, but are still not uncommon in small towns and villages. India has seen a massive decline of sparrows in recent years. On the world map too. Once a commonplace bird in large parts of Europe, its numbers are decreasing. In the Netherlands, the House Sparrow is even considered an endangered species. Their recent decline has earned them a place on the Red List in the Netherlands. Similar precipitous drops in population have been recorded in the United Kingdom. French ornithologists have charted a steep decline in Paris and other cities. There has been an even sharper fall in the urban areas in Germany, the Czech Republic, Belgium, Italy and Finland. History It is thought that the House sparrow originated in the Mediterranean and expanded into Europe with the growth of civilization. At the insistence of man did the sparrow make its way across the Atlantic to the United States. In 1850, green inch worms were destroying trees in New York City’s Central Park. As the house sparrow’s main diet in England consisted of the same green worms, it was thought that if sparrows were brought to New York City they would solve the worm problem in Central Park. Others thought the sparrow would eliminate crop pests. The first introduction of the sparrow was conducted by the Brooklyn Institute in 1851. Eight pairs were originally released but none were able to survive the change in climate. More attempts were made and eventually the birds adapted to a colder climate and multiplied. The sparrow rapidly spread across the United States. The abundance of spilled grain used for feeding horses and the artificial nesting cavities provided by humans helped the sparrow along. They successfu Food The house sparrow is an intelligent bird that has proven to be adaptable to most situation, i.e. nest sites, food and shelter, so it has become the most abundant songbird in the world. Sparrows are very social birds and tend to flock together through most of the year. A flock’s range covers 1.5-2 miles, but it will cover a larger territory if necessary when searching for food. The sparrow’s main diet consists of grain seeds, especially waste grain and live stock feed. If grain is not available, its diet y broad and adaptable. It also eats weeds and insects, especially during the breeding season. The parasitic nature of the house sparrow is quite evident as they are avid seekers of garbage tossed out by humans. In spring, flowers (especially those with yellow colours) are often eaten crocuses, primroses and aconites seem to attract the house sparrow most. The birds also hunt butterflies. Housing House sparrows are generally attracted to buildings for roosting, nesting, and cover. They look for any man-made nook or cranny to build their nests. Other nesting sites are clothes line poles with the end caps open, lofts, kitchen garden etc. The sparrow makes its home in areas closely associated with human habitation. Taxonomy The House Sparrow (Passer domesticus) is a member of the old world sparrow family Passeridae. Some consider it to be a relative of the Weaver Finch Family. A number of geographic races have been named, and are differentiated on the basis of size and cheek colour. Cheeks are grey in the west and white in the east. The shade of the colouration, particularly of the chestnut area in the males is also considered. Birds of the western hemisphere are larger than those in the tropical South Asian populations. In India, it is popularly known as Goraiya in the Hindi belt. In Tamil Nadu and Kerala it is known as Kuruvi. Telugu language has given it a name, Pichhuka, Kannadigas call it Gubbachchi, Gujaratis call it Chakli where as Maharashtrians call it Chimani. It is known as Chiri in Punjab, Chaer in Jammu and Kashmir, Charai Pakhi in West Bengal, and Gharachatia in Orissa. In Urdu language it is called Chirya while Sindhi language has termed it as Jhirki. Features This 14 to 16 cm long bird has a wing span of 19-25 cms. It is a small, stocky song bird that weighs 26 to 32 grams. The male sparrow has a grey crown, cheeks and underparts, and is black at the throat, upper breast and between the bill and eyes. The bill in summer is blue–black and the legs are brown. In winter the plumage is dulled by pale edgings, and the bill is yellowish brown. The female has no black coloring on the head or throat, or a grey crown her upper part is streaked with brown. The juveniles are deeper brown, and the white is replaced by buff the beak is dull yellow. The House Sparrow is often confused with the smaller and more slender Tree Sparrow, which, however, has a chestnut and not grey crown, two distinct wing bars and a black patch on each cheek The sparrow’s most common call is a short and incessant, slightly metallic cheep, chirrup. It also has a double call note- phillip wherein originated the now obsolete name of “phillip sparrow”. While the young are in their nests, the older birds utter a long churr. At least three broods are reared in the season. Reproduction The nesting sites are varied – in holes in buildings or rocks, in ivy or creepers, on houses or riverbanks, on sea-cliffs or in bushes in bays and inlets. When built in holes or ivy, the nest is an untidy litter of straw and rubbish, abundantly filled with feathers. Large well- constructed domed nests are often built when the bird nests in trees or shrubs, especially in rural areas. The House Sparrow is quite aggressive in usurping the nesting sites of other birds, often forcibly evicting the previous occupants, and sometimes even building a new nest directly on top of another active nests with live nestlings. Eggs are variable in size and shape as well as markings. Eggs are incubated by the female. The sparrow has the shortest incubation period of all the birds, 10 -12 days, and a female can lay 25 eggs each summer. The reproductive success increases with age and this is mainly by changes in timing, with older birds breeding earlier in the season. Causes of Decline There are various causes for dramatic decrease in their population, one of the more surprising being the introduction of unleaded petrol, the combustion of which produces compounds such as methyl nitrite, a compound which is highly toxic for small insects, which forms a major part of a young sparrow’s diet. Other being areas of free growing weeds, or reduction in number of badly maintained buildings, which are important nesting opportunities for sparrows. Ornithologists and wildlife experts speculate that the population crash could also be linked to a variety of factors like the lack of nesting sites in modern concrete buildings, disappearing kitchen gardens, increased use of pesticides in farmlands and the non- availability of food sources. K.S. Gopi Sunder of the Indian Cranes and Wetlands Working Group says: “Although there is no concrete evidence or study to substantiate the phenomenon, the population of house sparrows has definitely declined over the past few years”. He attributes this to a number of reasons. The widespread use of chemical pesticides in farmlands has resulted in the killings of insects on which these birds depend. “Seed-eating birds like sparrows have to depend on soft- bodied insects to feed their young ones,” he said. The other possibility could be increased predation by crows and cats, while crows have grown in number as a result of garbage accumulation in the city. According to Dr. V. S Vijayan of the Coimbatore-based Salim Ali Centre for Ornithology and Natural History, though the avian species can still be spotted over two-thirds of the world’s land surface, “ironically, there has been a rapid decline in the population of these once abundant birds”. Changing lifestyles and architectural evolution have wreaked havoc on the bird’s habitat and food sources. Modern buildings are devoid of eaves and crannies, and coupled with disappearing home gardens, are playing a part in the disappearing act. Today one misses the sight of sparrows hopping from branch to branch in the bushes outside one’s house and their chirping. One is taken back to well known Hindi Writer Mahadevi Verma’s Story ‘Goraiya’ – eating grains from her hands, jumping on her shoulders and playing hide and seek. Today one wishes that the Goriya does not remain confined in the pages of Mahadevi Verma’s story but comes back to our cities as ever before.