Written by Meghna Agarwal Wednesday, 21 December 2011 05:15
It is past October and the season for the migratory birds in India has begun. Lakhs of migratory birds fly thousands of miles to reach various parts of South Asia and make it their home for the winter months. The Indian coasts are already teaming with migratory waders, plovers, gulls and terns.
"The usual month of the arrivals of the coastal birds is October and the coasts are already teaming with our migratory waders, plovers, gulls and terns. The migrants arrive in waves and each species arrives at a slightly different date. These waves continue up to January. The approximate numbers of these migratory birds are about 24 % of our bird species and the number of species recorded from India is between1200 to 1300" Pune-based ornithologist Satish Pande said.
But the numbers of these migratory birds in India is dwindling at a great speed. The threat is so severe that we are forced to ask whether our future generations will know what are migratory birds? Even if they happen to know and read about it theoretically, will they happen to see a flock of Bar-headed Geese flapping their wings playfully in the water. Or a group of Siberian Cranes covering the winter sky in the Saurashtra region.
"The species like the Bar-headed Geese and the Demoiselle Cranes have reduced in their numbers. Several species of ducks have witnessed a decline. The population of the Siberian Crane that was coming to India has probably become extinct," Pande said.
Arrival of migratory birds in India
Over the years, the arrival pattern of migratory birds in India has constantly been on a decline which went unnoticed despite the cries of bird watchers all over the country, thus making the current situation reach a critical stage.
During December several birds from the colder regions are spotted at several places in the country. Small birds like flycatchers arrive in early November. Wagtails usually arrive in mid-October. Ducks come by end of October or early November in huge numbers.
Almost 80 per cent of migratory birds did not turn up in 2010. At least 15-16 varieties of ducks arrive every year but in 2010 there were hardly any despite of abundance of water. The only species present last year were the northern shoveller, a few wigeons and the brahminy shelduck and pintails. Species abundance and diversity both have reduced. Waders (long-legged wading birds), little-ringed plovers and others like the Kentish plovers, greenshank and redshank and were only a few in 2010. Birds of prey such as the montagu harrier, pale harrier, hen harrier and the pied harrier that come from Eastern Europe, Central, Northern Asia and Southeast Asia did not arrive in 2010. The biggest change has been observed in the migratory patterns of water birds.
Due to changing crop pattern, the no of cranes coming to India over the years has reduced by as much as 75 per cent. As many as 4,000-5,000 bar-headed geese were sighted in the past. But in the last two years, flocks of only 40-50 of these birds were seen at one time. The number of geese has definitely reduced by 50 per cent.
Changing crop pattern, use of pesticides and loss of habitat have led to loss of as much as 80 per cent of migratory birds' arrivals to the wetlands of the country, including Maharashtra, Uttar Pradesh, Gujarat and Rajasthan in 2010. Loss of habitat is a bigger deterrent. Agricultural pesticides enter water habitats and they are also filled up for construction. Both the things have affected bird migration.
"The reasons for the decline in the numbers and species compositions of migrants could be their reduction in numbers in the breeding grounds or non-conducive habitats in the places of arrival. The reasons for these are habitat destruction and modification, indiscriminate use of pesticides and hunting. Another important reason in our country is change in crop pattern in the areas of their final destination. The Demoiselle Cranes have stopped visiting several areas in Central and South India because the lentil crops are replaced by sugarcane," Pande, who has authored a dozen books of these aerial creatures, said.
On several occasions, the arrival of the migratory birds in India is delayed. Rainfall even after monsoon has delayed their arrival. Birds find it difficult to migrate in the rain because it hampers their flight. They may get exhausted and die. Humid and cloudy conditions lead to low visibility. Inland migrants and forest birds like the warblers, migratory predators such as greater spotted eagle, lesser spotted eagle, imperial eagle, northern goshawk, sparrow hawk, peregrine falcon, saker falcons and the short-eared owl were late in 2010.
"The migratory birds come to India to escape from the harsh vagaries of the northern winter when the daylight hours and food are short. The temperatures in the native country of the bird (where it breeds) are harsh and survival is at a premium. They leave their home to find optimal conditions of climate and enough food. If the northern winters are delayed, the departure times of the avian migrants are also correspondingly altered." Pande said.
Presently, due to the global warming (that is more evident in the northern latitudes than in the tropics), the departure dates of many of the migratory species are postponed and this has an alarming significance because the food cycles and arrival times of migrants in the tropics become asynchronized. The migratory birds in India may find the important source of food becoming scarce. This can in turn have a negative effect on their overall health and subsequent ability to complete the return migration and breed." Pande added.
Lot of wetlands in Gujarat and Bharatpur are the first stop for most of the migratory birds. "Saurashtra gets the common and demoiselle cranes. Bharatpur in Rajasthan and Khijadiya in Gujarat. Jamnagar has wetlands and coastal birds. Migratory ducks fly to Bharatpur, Pande, a radiologist by profession said.
Migratory birds begin arriving from north India, central, Western Europe and Siberia in October. The majority of the avian migrants come to India from the north and beyond the temperate latitudes. These come from Asia Minor, Arabia, Central and NE Asia, East Asia and Europe. A few come just beyond our northern boundaries from adjacent Tibet and China. However, some migrants also come to us from Australia.
Nature conservation through education can help get us back the lost numbers of migratory birds in India. "Importantly we should identify the habitats and places where migrants arrive and protect them. We should educate local people and children about the various facets of bird migration. Unless the common man is sensitized conservation shall be ineffective. The grass root level effort shall yield results. Hunting should be stopped. Use of inorganic pesticides alone should be reduced by supplementing organic pesticides. The bio-control of pest by promoting the usefulness of natural predators should highlight," Pande, who has founded ELA Foundation, an organisation devoted to nature conservation through education said.
"Importantly what needs to be done today on a priority basis is to buy and keep aside large tracts of land and not to develop them for human needs, but to allow the natural successions of natural bio-diversity diversity to occur," Pande added.
"It is always a pleasure to watch the beautiful and strong birds, the masters of the sky, and is always challenging to photograph them on the wings," Pande said. But whether these agile, strong and beautiful birds will continue to visit us actually depends on us. In the temples of nature wild life shall truly flourish and become safe. And it is on us to protect the ecosystem so that migratory birds in India can come and delight us.