Delta smelt

Delta smelt (Hypomesus transpacificus) is an endangered slender-bodied smelt, about 5 to 7 centimetres (2.0 to 2.8 in) long, in the family Osmeridae. Endemic to the upper Sacramento-San Joaquin Estuary of California, it mainly inhabits the freshwater-saltwater mixing zone of the estuary, except during its spawning season, when it migrates upstream to freshwater following winter "first flush" flow events (around March to May). It functions as an indicator species for the overall health of the Delta's ecosystem.

Delta smelt

Delta smelt (Hypomesus transpacificus) is an endangered slender-bodied smelt, about 5 to 7 centimetres (2.0 to 2.8 in) long, in the family Osmeridae. Endemic to the upper Sacramento-San Joaquin Estuary of California, it mainly inhabits the freshwater-saltwater mixing zone of the estuary, except during its spawning season, when it migrates upstream to freshwater following winter "first flush" flow events (around March to May). It functions as an indicator species for the overall health of the Delta's ecosystem.