Question

how is environmental pollution affecting bird population in india

Answer 1

There has been a lot of change in the physical environment of our country in the past five decades, notes eminent ornithologist Zafar Futehally. "In the early 1950s, in our gardens in Andheri, Mumbai, there were jungle babblers (Turdoides striatus), magpie robins (Copsychus saularis), golden orioloes (Oriolus oriolus) and many more birds. Now there are nothing but crows in the same area," he rues.

Why are birds becoming fewer? The reasons are many and often complex. Habitat fragmentation and chemical contamination have proved hazardous for those that have a short range and also a short life span like Jerdon's courser (Rhinoptilus bitorquatus; see box Small range, greater threat). Other birds like the great Indian bustard which require specific habitats are threatened when their habitats get degraded (see graph Bird killers).

Chemical scourge in wetlands Wetlands are among the main habitats of birds in India about 20 per cent of birds depend on them. These aquatic areas are under serious pressure. During a 1999 nationwide sarus crane census, for example, many participants noted that wetlands were polluted with domestic and industrial waste, pesticides and fertilisers. "The problem gets compounded because no state in India includes wetlands in its land use statistics. So unprotected wetlands are vulnerable to land use change," says Ritesh Kumar of Wetlands International, Delhi.

Lalita Vijayan of the Salim Ali Centre for Ornithology and Natural History (sacon), Coimbatore, notes that a study on wetlands conducted by her organisation revealed that "fish in wetlands had residues of heavy metals and pesticides, some at levels far above those prescribed by who."

The Indian skimmer (Rynchops albicollis), once common in the river systems of north India, is one bird whose habitat has become unsafe because of chemical contamination. It is categorised as vulnerable in iucn's Red List. "This bird's requirements overlap dangerously with those of people," says A R Rahmani of bnhs. Experts such as him say increased use of pesticides in cultivation of fruits like melons on the banks of large rivers is reducing the breeding sites for the skimmer.

In the Red List, the status of the falcated duck (Anas falcata) and black-tailed godwit (Limosa limosa) changed from 'least concerned' in 2002 to nearly threatened in 2006; that of the sociable lapwing (Vanellus gregarius) and the spoon-billed sandpiper (Eurynorhynchus pygmeus) changed from vulnerable in 2002 to critically endangered and endangered, respectively, in 2006. Significantly, all these are water birds.