Mystery of the missing birds Well, Mrinalini, bird-watchers across the globe are trying to find an answer to this!

Because the skylines of almost all the cities in the world today are haunted by this ‘Mystery of the missing birds’. Listen to this. According to a study conducted by the British Trust for Ornithology (BTO), there has been a 75 per cent drop in the population of sparrows in London during the past decade! In fact, it looks like the entire country is going sparrow-less. 30 years ago, there were about 24 million of them, now less than 14 million can be traced. And as these ornithologists delve deeper, they are coming up with some pretty scary facts. In the last 300 years, out of 8700 species of birds world over, 80 have become extinct. Today the rate of extinction is more than one per year. Clueless in India But at least in Britain they are counting. In India we are not. The disappearance of sparrows in India, too, has been widely reported. But since we have no reliable scientific documentation on bird populations, we don’t know how many we have lost already. No one is monitoring or keeping records. And this is true not only of sparrows but most of the common bird species in our country. Just because they used be found in abundance, we just assumed that they would remain ‘common’ always. Now that the alarm bells are ringing furiously worldwide, we have been jolted out of our slumber. The search has begun for the sparrows, the parakeets and the swallows.

Death due to poisoning?
What are the basic things required to keep the birds alive? Safe and sufficient food, water and a comfortable nest, right? But what if the grains and insects they feed on are poisoned? What if loads of chemicals are put into the rivers and water bodies that destroy the fish population and pollute the water they drink?

Yes, the birds are being poisoned, slowly.

But we have not uncovered any new fact here. This damaging piece of evidence was first revealed in 1962, by Rachel Carson in her book, Silent Spring. Carson told a shocked global community how pesticides sprayed on crops was wiping out bird populations and even entire species in the United States.

Pesticides such as Dichloro-diphenyl-trichloroethane or DDT, were sprayed by farmers in the United States to get rid of pests and worms—hoping for a bumper yield. But what they did not know was that the chemical was lethal not only for the pests but for birds, and animals as well. Realisation dawned when the lilting notes of the American Robin, that heralded in the spring season, were silenced. The robins were dying, and so were the swallows and owls. DDT had ushered in a silent spring…

Carson first warned us that the use of chemicals in agricultural farms was polluting food and water and that this process could have a dangerous impact on animals and humans alike. It was already leading to genetic damage and death of species. And the US government put a ban on DDT.

In India, too, we have stopped spraying it in the agricultural fields. But it is used by the public health departments of the government to get rid of mosquitoes — carriers of the deadly malaria virus. Why? Because, unlike in the US, such vector (carrier)-borne diseases are very common in India. They often erupt in epidemic scale. And in such emergency situations, DDT remains the cheapest and the most effective weapon to deal with the crisis.

Anyway, substituting DDT with other varieties of pesticide has not really solved the problem for the birds. Because these chemicals now kill the worms that the birds feed on, forcing some species to literally starve to death. This is how it happens.

Vanishing vultures The frightening fact is that even the more hardy birds are dying. Take the case of the vultures, nature’s winged scavengers. Since 1997, about one lakh vultures have disappeared in India. No one has been able to pinpoint the actual reason behind this, till today. While some scientists believe that it is due to the lethal effect of a drug called Diclofenac sodium, used to treat sick animals, which is then passed on to the vultures that feed on dead cattle, others blame it on the intake of pesticides. Whatever the reason is, the vanishing vultures are causing serious concern worldwide. Why? Because the scavenger birds help cleanse the natural ecosystem of decaying carcasses. And, keep the cities and villages free of diseases.

Nothing to peck on…

On an average, a sparrow or a starling or a mynah eats about 1000 worms and insects in a year. Certainly a better way of getting rid of these pests than using chemical pesticides that are known to have harmful side effects! These poisons, on the other hand, kill caterpillars and soft worms—which form the basic diet of infant sparrows. While adult sparrows can survive without insects, they do need them to feed their young. Result? Infant mortality rate is extremely high among sparrows, swallows and starlings.

But the farmlands are in the villages, how are the poisons sprayed here affecting city birds? "The chemicals are not only infecting the worms but the soil and the water as well. Streams and rivulets carry the poison from agricultural fields to the towns and cities. And people living in cities use pesticides in their gardens, too. Ponds, lakes—all urban water bodies—are polluted. So how can the urban birds, which drink from these, and peck on the fish, remain immune?", explains Lalitha Vijayan of the Salim Ali Centre for Ornithology and Natural History (sacon).

Next Page

1 2 3