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Migratory Fish, Dams, and Ecosystem Service Tradeoffs


Speaker: Dr. Alexander Flecker, Cornell University

Hydropower is proliferating rapidly in some of the largest and most biodiverse rivers in the world. For example, in the Amazon basin, more than 150 large dams have been built and some 350 large dams have been proposed. Dams can have many adverse environmental and social consequences including blocking migrations of fish that people rely on as sources of protein and micronutrients.

This talk will first address the functional significance of migratory fish in tropical river systems, and how dams can result in a loss of migratory species that help shape the structure and function of riverine ecosystems. The talk will then explore strategic river basin planning, and some of the tradeoffs between hydropower, river connectivity, and other ecosystem services in two large South American river basins, the Amazon and the Magdalena.

Results of this research show the importance of considering a broad suite of environmental criteria for assessing where to locate dams with the least amount of environmental damage. Work in the Amazon reveals the importance of strategic planning at the whole-basin scale, and points to the critical need for international cooperation for reducing adverse impacts of hydropower expansion in transboundary basins.

This event is free and open to all.

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