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Creature Feature: Decline of Small Delta Fish Predicts Health of Environment

The Delta smelt (Hypomesus transpacificus) may be a tiny fish, but this indicator species’ lack of presence looms large in California’s water allocations as it nears closer and closer to extinction despite being protected by the Endangered Species Act.

An indicator species is defined as a species whose presence or absence in a specific environment is a direct correlation to that environment’s health and condition. In this case, the Delta smelt, which is considered threatened, is an indicator species for the Sacramento-San Joaquin River Delta.

See the Creature Feature card below to learn more about the Delta smelt and what's causing the population decline.

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