CONTENTS-
Introduction
Study Area
Methodology
Results
Discussion
Conclusion

The need to maintain and enhance the urban and suburban populations of wild life has greatly increased in recent past due to a desire to observe wild life closer to home and a concern to protect the habitat from rapid urbanisation.   There is an urgent need to foster wild life awareness among the urban dwellers so that policies on wild life and protection issues can be better evaluated. Planners who take environmental decisions based on limited information available on biological components of the area to be impacted also become misleading.   Therefore I strongly feel that habitat requirements of individual species must be known before the implementation of management or planning schemes.   Many studies have discussed the necessity for information about the habitat components that are important in the urban areas and have emphasised that there is a need for more research on wild life in areas to obtain detailed knowledge on the characteristics of urban fish and wild life population. Planning for wild life in urban areas is often stifled by inadequate support and lack of collaboration from resource agencies and awareness of importance of lakes and expertise in wild life matters by urban planners.   City planners have ultimate responsibilities for incorporating wild life issues in to the planning process. But the results are not encouraging.

The solution to this dilemma is either to encourage greater collaboration between wild life regulatory agencies, municipal planners or to familiarise the planners with wild life resources through literature relevant to both the disciplines.   This study is a humble attempt to identify life forms in a city lake and to learn and recommend the habitat requirements of the animals. The major water bodies of India are facing serious threats of aquatic pollution consequent to urbanisation and industrial growth.   Domestic, agricultural and industrial wastes are being indiscriminately discharged into aquatic ecosystems.   At present environmental studies seem to be focused more on water quality parameters than on the total ecological changes brought about in the aquatic systems.   It was therefore thought it would be interesting to make a preliminary survey of the pattern and impact of various industrial and other effluents   on the Madiwala lake.

Madiwala Lake is a fresh water lake extending to about 114.16 hectares in the B.T.M. layout   on the Bangalore - Hosur highway about 8 kms from the heart of the city.   The total water-spread area of the lake is 750803 sq. m and the total wetland area in 24.74 acres.   The water holding capacity of the lake is 2236737 cubic meters. Residential areas surround the lake and there is a small island in the centre with moderate vegetation of bushes and under growth of tall grass and even ornamental plants.   The lake is almost fully covered by Eicchornia except for about 30 to 40 hectares towards the north-eastern side where the Bangalore City Corporation has cleared the weeds under the Indo-Norwegian environment programme.   Towards the northeast corner to the lake, a dhobi-ghat is functional .

The study area was visited four times during the month of October.   Location, boundaries and zoogeography of the area were noted down.   Household   garbage, plastic bags, paper, detergents etc. are thrown into the tank.   The lake is also contaminated by faecal matter. Physical examination of the water samples was done for clarity, weed growth etc.   Life forms in the area was observed and noted through naked eyes and also with the aid of an 8 x 40 Zenith prismatic binocular.

This vast expanse of freshwater ecosystem in addition to its aesthetic beauty and recreational value is a potential habitat for various forms of invertebrates and vertebrates but the main threats to the system include the direct or indirect influence of various types of human activities.   Domestic sewage, Industrial wastes, detergents, etc. that are indiscriminately dumped into the lake results in eutrophication, oxygen depletion and consequent reduction in aquatic life especially fishes.   The organic wastes dumped into the system also accelerate the multiplication of floating weeds affecting light penetration into the deep water.   Faecal contamination of water by the slum dwellers in the bank of the lake in addition to making the whole place stinking    also enhances the multiplication of coliform bacteria.

Immediate restoration strategies include:

1.             Cleaning the water of all floating weeds, which prevents light penetration.   At present this is carried out in phases since Eicchornia multiplies very fast and its removal has to be done at a single stretch.   Otherwise it will result only in huge loss of money.

2.          Washer men in the bank of the lake should be rehabilitated and provided with alternate source of water.

3.             Management strategies should focus on bank vegetation that supplies    cover and food to birds, amphibians etc.   A natural buffer of vegetation should be developed along the wetland margins.

4.          The slum dwellers along the banks of the lake should be rehabilitated or provided proper toilet facilities.

5.          As an effective measure for further diversity, detritivorous fishes, turtles etc. could be introduced in the lake.

Christ College, Bangalore, India.