The river floodplain ecosystems of the Sahelian region have recently undergone two major hydrological changes: (i) increased interannual variation in rainfall and (ii) a steep reduction of flood peaks and floodplain inundation following the construction of a number of dams and increased water abstraction. Fishers have little freedom of movement within the delta to help them cope with environmental changes. The only new opportunities are those offered by new reservoirs. Most fisherfolk farm traditional rice as a secondary activity, but farming cannot replace fishing, which brings in steady, substantial cash income for much of the year. Fishing and rice farming are complementary, but fishers cannot shift completely from one to the other. Although migration and diversification are often presented as strategies to reduce vulnerability, recent data from the Inner Niger Delta demonstrates that these strategies alone are insufficient to cope with the worsening constraints that come with changes in hydro-climatic conditions.