Why should I care about a smelt?

The Delta smelt is a two- to three-inch fish native to the Sacramento-San Joaquin Estuary, where it lives in the freshwater-saltwater mixing zone except when it migrates upstream to freshwater to spawn.  It has a short (one-year) life cycle and is very sensitive to changes in flows and other habitat conditions.  Thus, adverse conditions that could later affect other aquatic species may affect Delta smelt first.  While the Delta smelt is not as well-known or useful to humans as the Chinook salmon that also depend on adequate Delta flows, the health of the smelt is an indicator of the health of the estuary as a whole.  It is somewhat like a caged bird in a coal mine that dies first if there are dangerous gases present that could kill miners.

Reductions in the numbers of Delta smelt have coincided with increases in water exports over the past 40 years that have dramatically altered freshwater flows.  Delta smelt have been listed as threatened under the Endangered Species Act since the 1990s, and exports have been reduced on numerous occasions in attempts to protect them.  No one disputes that millions of smelt have been killed at the export pumps in the south Delta, and other stressors such as predation and poor water quality have also contributed to their decline.

In an effort to maintain preferred levels of exports for the State and federal water projects, the Bay Delta Conservation Plan (BDCP) has focused on changing where or when freshwater is taken from the Delta and on creating habitat in hopes that it will compensate for changed environmental conditions that harm Delta smelt and other species.  However, no planning effort has seriously considered reduction of water exports to levels that can be sustained through both wet and dry years so that all fish have enough freshwater to recover and thrive.  Without that, no other efforts to protect the environment for fish and other species will be successful.