Lakes can't host avian guests

Lakes can't host avian guests

Lakes dried for cleaning means habitats of migratory birds are destroyed, say ornithologists. BDA officials, however, are in a bind — many of the city's lakes are so laden with chemical and organic wastes that there is no better way to protect the ground water from further contamination than drying and de-silting, they say

Bosky Khanna. Bangalore



Restoration work being undertaken by the Bangalore Development Authority (BDA), of 12 city lakes. The cost of the work is over Rs100 crore, and it will go a long way in providing safe drinking water to Bangaloreans. But is this the best way to preserve the city's eco-diversity? Will it protect the wetland habitat of migratory birds?
Ornithologists say that a healthy lake eco-system means not just clean water, but also healthy aquatic life and bird population. Completely drying up 12 lakes, including the one in Jakkur, during the peak season for migratory birds, is shockingly insensitive. Jakkur lake, at present, houses mostly egrets and little cormorants; the migratory birds have flown.
Bangalore has been home to over 20 species of winged beauties from across the world in the November-March period. Speaking to DNA, honorary wildlife warden and noted ornithologist Harish R Bhat said, "Drying lakes is not a scientific cleaning method. It disturbs the natural eco-system, irretrievably. Birds do not return, even if the lake is later restored. They gradually move to other lakes."
"Instead of drying up the lake, the authorities would do better to adopt the wet dredging method, which is slightly more expensive. Experts at the Indian Institute of Science and other ornithologists have already made this recommendation, as water, micro-organisms, flora and fauna all are needed in a healthy lake environment. Migratory birds feed on fish and aquatic plants, which get killed as lakes are dried," Bhat said.
Migratory birds fly in from short distances away as well as from many thousands of kilometers away. The pelicans, painted stork, ibis and open-billed stork all fly in from nearby places, while distant migratory birds are pochard, pin-tailed duck, shoveller, bar-headed goose, flamingos (occasionally), white stork and smaller birds like sandpiper, booted warbler and blyth's-reed warbler.
Experts point out that the Hebbal lake, which over its 60-acre expanse once housed a healthy migratory bird population, has not remained the same since it was privatized and leased to the East India Hotels for de-silting and recreation. Two years after that work was undertaken, the bird population has yet not revived. There are migratory birds that come from Siberia, European countries and other parts of Asia to the city.
BDA officials, however, point that the lakes were highly polluted, with both organic and chemical waste. Lead, calcium, nitrate, fluorides, magnesium and iron were found in the lakes, thus completely drying them is essential. The de-silting process will be undertaken so that ground water is not further contaminated with the chemicals, assert officials.
Lakes to be rejuvenated
Jakkur, Sampigehalli, Rachenahalli, Venkateshpura, Ullalu, Mallathahalli, Komaghatta, Ramasandra, Thalaghattapura, Konasandra, Sompura and KothanurPolluting Before cleaning: People wash bags that contained chemicals on the banks of the Ullalu lake, set to be cleaned by the BDA