Status of water birds in the tanks of North Bangalore

1. Status of water birds in the tanks of North Bangalore Harish R. Bhat Centre for Ecological Sciences Indian Institute of Science Bangalore 560 012

2. Introduction: Wetlands: lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface, or the land is covered by shallow water.Almost all tanks Bangalore are manmade, built for the welfare of the society.Of late, Wetlands are de-valued as unhealthy "wastelands”!!!

3. Karnataka State had about 44,000 man-made wetlands constructed over centuries beginning with the Vijayanagara Dynasty At present only 36,969 wetlands exist in Karnataka! Bangalore alone in the past had 400 tanks, but now only 130 tanks are left with just 36 ‘live’ tanks….. In the past, peoplesacrificedtheir lives for the sake of building tanks,But now a days many tanks are‘sacrificed’in the name development 

4.  Water Birds and Wetlands • Indicators of lively wetland ecosystem • Depend for food, shelter • Aesthetic value to the wetland • Ecological Importance • Haven for bird watchers

5. Annual Water bird survey Annual water bird count is conducted during 5th and 26th of January 11 tanks (Ardeshanahalli, Doddatumkur, Hebbal, Hesarghatta, Jakkur, Kolthur, Madhurekere, Nagavara, Puttenahalli, Singanayakanahalli and Yelahanka) situated at the North of Bangalore are surveyed Tank condition, other activities in the tank region, different species of birds along with their numbers are documented

6. Findings: • Till 2004, all the 11 tanks were in better condition, with sufficient water, fish population • About 42 species of water birds and water dependent birds were documented during the census • Hesarghatta had about 2000 birds belonging to29 species, but had noticed bird traps at the bunds! • Hebbal and Puttenahalli had more than 400 birds belonging to 4 species respectively • Totally about 5000 birds were documented from all the 11 tanks

7. Findings: In 2004, due to severe drought, 7 of these tanks were in a bad shape being totally dried up These were used for sheep and cattle grazing, temporary vehicle parking places!! Dumping of debris were noticed at the tanks Winged visitors (Painted Storks, Open-billed Storks, Spot-billed Pelicans and other birds) were dependent on the remaining 4 (Puttenahalli, Madhurekere, Nagavara, Hebbal) tanks that had considerable amount of water

8. Findings: In 2003,Madhurekere had 190 Painted Storks and other birds such as Spoonbill, White Ibis, Grey Heron, Black-winged Stilt, Sandpipers, River Tern, Pin-tailed Duck, Spot-billed duck But in 2004, not even an Egret or a Pond Heron were noticed in the same tank Hebbal tank was as usual rich with Pin-tailed duck, Spot-billed duck, Common Pochard, Garganey Teal, Sandpipers, Black-winged Stilt, River Tern, Grey Heron, Purple Heron, Kingfishers, Purple Moorhen, Common Coot and other birds

9. Findings: 4th June 2003 The tank was 95% dry due to drought Many birds were found dead at the Hebbal tank The death remains unsolved though it could be due to drought, lack of water, food availability, increase in temperature and poisoning Sparse water at very small area congregated many fishermen and water birds competing for fish

10. Findings: 2005- 2006 was fair enough for the winged visitors as the tank condition was better with sufficient water and thus getting back most of the water birds back to the garden city The bird survey proved rich at Puttenahalli, Madhurekere, Hesarghatta and Hebbal tanks But Nagavara tank, being leased (2005) to Lumbini gardens, developed into a ‘swimming pool’ rather than a ‘live’ tank! Hardly very few birds like Little Cormorants, Pond Herons and Common Coots This year yet another tank is being leased to Oberoi- Hebbal tank!

11. Findings: Traditionally community based organizations were protecting the catchments and regular maintenance including desilting these tanks With low population densities and little industry, pollution was no threat, nor had many exotic weeds been introduced Many pressures on land have led to encroachment of tanks and tank beds Such kind of ongoing changes will definitely block the water draining pathways, leading to floods Tanks- sinks for sewage and industrial wastes

12. Conclusion: Protecting of remaining tanks from being ‘sacrificed’ for developmental purpose Flooding will be common phenomenon as all the catchments areas and tanks would be encroached, thus failing water drain War for Water could be predicted in 2025, as almost all tanks would be sacrificed and converted landfills and further developed Water birds, being good indicators for best wetland ecosystem might permanently shift their roost to other states

13. Recommendation: • Re-trace the water draining pathways, map them and provide the lost links • Clear the already encroached areas by providing the alternatives and make the water draining pathways free from disturbance • Alternative measures to divert the inflow of effluents • De-weeding of aquatic weeds • Afforestation programme to be undertaken by planting native species • Transfer the tank rights to the local villagers, organization and build the bridging gap between the decision makers and the stake holders for the betterment of remaining tanks