Sustainable hydropower development in the Mekong River

Background/Question/Methods

Hydropower development plans threaten the large fish biodiversity of the Mekong River. In particular, the conservation of over 90 migratory species depends on maintaining connectivity between upstream spawning sites and feeding regions in the downstream floodplains. To analyze impacts of dam construction, we develop a model in which one migratory species travels between two habitats, co-populated by a resident species.

Results/Conclusions

The model shows that costly migration can be compensated by moving to a better habitat for part of the year. Flow modifications reduce migration success, and can cause species extinction even if fish passes are constructed. Some implications relevant to the Mekong River would be discussed.