FRESHWATER COMMUNITY ECOLOGY AND CONSERVATION

Over the last century, an ever-increasing pressure on freshwater and its resources is driving many of our freshwater ecosystems and their fauna into decline. An understanding of the processes and mechanisms that structure and regulate stream fish assemblages is crucial. Therefore, conservation priorities for specific streams and their fish fauna should be based on a clear knowledge of the ecological factors that determine spatial and temporal patterns of species diversity and distributions.

Our research is currently based on fish communities of medium to small sized streams located in central India and north Bengal regions of the Indian subcontinent. Regular fish and ecological data are being collected from selected sites in these streams and these are used to address several questions.

Species diversity and distribution patterns are known to be driven by local as well as regional processes. Specifically, local processes such as immigration, extinction, microhabitat characteristics, along with disturbance from human activities can drastically affect community structure. At the regional scale, factors such as stream discharge rates, rainfall patterns, land-use changes along riparian regions can further affect species diversity and composition.

Questions we ask- What are the key ecological factors that determine fish diversity and composition patterns in streams along human impacted ecosystems? How do these factors differ across eco-regions? How do local processes such as immigration and emigration rates, disturbance etc. affect community structure?

Our understanding of the processes that play key roles in shaping fish communities in our study areas can be used for conservation studies of vulnerable and endangered habitats and their fish fauna. Predictive models based on generalized modelling and artificial neural network methods are being used to select important ecological factors. There can then be used for developing conservation prioritization strategies.