Replacing Something That Doesn't Exist: Regulatory, Social, and Biological Issues for Reintroduction of Chinook Salmon into the San Joaquin River

Spring-run Chinook salmon (Oncorhynchus tshawytscha) were extirpated from the San Joaquin River over 60 years ago when Friant Dam operations were brought fully on line and large stretches of the river became dewatered.  Remaining Central Valley spring-run Chinook salmon populations are listed as threatened under the Endangered Species Act (ESA). Fall-run Chinook salmon persist in dwindling numbers in the large tributaries to the system, but are not listed under the ESA. A legal settlement calls for the reintroduction of these salmon runs.  The enabling statute requires use of the ESA experimental population designation and 4(d) rule to avoid impacts to third parties that could result from such reintroduction.  The first use of an experimental population designation for an anadromous fish has been proposed in 2011. Significant challenges exist to address these requirements while successfully establishing the new runs. Various methods are being employed to obtain sensitive information needed for crafting these rules, while protecting proprietary information, and creative approaches are required. These methods may be useful to other efforts to develop safe harbor or experimental population rules for highly migratory and anadromous fish species.