Status of water birds in the tanks

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Status of water birds in the tanks of North
Bangalore
Harish R. Bhat Centre for Ecological
Sciences Indian Institute of Science Bangalore
560 012
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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!!!
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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, people sacrificed their lives for
the sake of building tanks,But now a days many
tanks are sacrificed in the name development 
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•  Water Birds and Wetlands
• Indicators of lively wetland ecosystem
• Depend for food, shelter
• Aesthetic value to the wetland
• Ecological Importance
• Haven for bird watchers

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  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
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• 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
•  

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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

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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

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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
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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!
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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
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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
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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