Protecting fish from California's extreme drought
It seems intuitive that fish need water, but with California facing its driest two-year period on record, water is becoming harder and harder to come by. To ensure California’s threatened and endangered fish populations survive the drought, NOAA is working hand-in-hand with the state and other federal agencies on water, fisheries and wildlife strategies.
Historically, salmon and steelhead populations were geographically widespread throughout the central and northern California coast. Their habitats were pristine, connected, and better able to withstand natural drought cycles. Today most populations stand at a mere fraction of their historical size due to habitat degradation and other factors. They are more vulnerable to extreme weather conditions than ever before.
The impacts of the current drought are widespread and include low river flows, reservoir levels, and snow packs. The limited water supply poses challenges for water managers tasked with balancing the needs of ranchers and farmers with bustling urban centers. It also requires fish and wildlife managers, including NOAA, to revisit protections for vulnerable fish species.
NOAA’s efforts to safeguard threatened and endangered salmon and sturgeon are guided by the Endangered Species Act, typically through two main vehicles: 1) biological opinions, which provide guidance to federal agencies to ensure their actions avoid harming listed species; and 2) species recovery plans, which include longer-term strategies to recover the species to healthy numbers, at which point they no longer need ESA protections. The protective measures contained within both these documents account for inherent variability in annual conditions.
Lake Shasta, January 2014. Photo courtesy of California Department of Water Resources
In the Central Valley, for example, a long-term recovery plan outlines strategies to protect endangered and threatened salmon and steelhead runs so that droughts do not inhibit their long-term recovery. This includes increasing the distribution of the populations into historical spawning and rearing habitats. By doing so, populations are not constrained geographically and thus at greater risk of a catastrophic event, like drought, causing their extinction. For instance, NOAA is currently working with partners to reintroduce a population of spring-run Chinook into the San Joaquin River Basin which, over time, will support a greater geographic distribution of the species and ensure it’s able to tolerate environmental variations.
Water pumping operations at federal and state facilities impact Central Valley winter and spring-run Chinook salmon and steelhead, as well as other species. A 2009 biological opinion issued to the U.S. Bureau of Reclamation prescribes ways in which to operate the water system to minimize harm to these species. Measures included increasing the cold water storage and flow rates to enhance egg incubation and juvenile fish rearing; as well as improving spawning habitat and migration conditions.
Oroville Lake, January 2014. Photo courtesy of California Department of Water Resources
Providing sufficient and cool water flows in warm, critically dry years such as this is difficult. Each year, federal, state, and local agencies examine water conditions, including demands, to modify releases. The federal agencies are coordinating efforts to accelerate water transfers and exchanges, provide operational flexibility to store and convey water, expedite environmental review and compliance actions, and pursue new or fast-track existing projects that might help stretch California’s water supplies. The agencies are seeking maximum flexibility in carrying out water supply operations, investing in conservation measures and coordinating with the California State Water Resources Control Board to implement any new operational standards.
Operations are also being affected by the drought in the Klamath River Basin. The Klamath Project consists of an extensive system of canals, pumps, diversion structures, and dams capable of routing water to 200,000 acres of irrigated farmlands in the upper basin. Water diversions from Upper Klamath Lake affect river flows downstream of Link River and Iron Gate dams, which in turn affect threatened coho salmon. To protect fish and provide for irrigation, the Bureau of Reclamation manages flows based on real-time climate and hydrologic conditions. During drought years, Reclamation operates the Klamath Project to provide minimum flows at Iron Gate Dam to ensure adequate instream flows for coho salmon.
Due to the extremity of the current drought, NOAA Fisheries is working with the California Department of Fish and Wildlife to rescue fish stranded upstream by lack of water. Recently, volunteers took endangered coho, one by one, from Scott Creek near Monterey Bay, and relocated them to a nearby hatchery. The fish will remain there as captive broodstock so their eggs will be available to boost future runs and assure genetic diversity in the population. In this year of extreme drought, other such fish rescues are likely.
The many challenges salmon face this year also affect their out migration to the ocean, where they will continue to grow for two to three years. We will only feel the full impact of the drought in several years when the fish are due to return as adults, and when the ocean fisheries would take place. At this time, it is difficult to predict exactly how the drought while shape future commercial and recreational fishing.
Responding to the year’s drought requires federal, state, and local partners to work together in a coordinated manner. Many of the actions to protect salmon will also benefit other fish and wildlife species. In addition, NOAA’s expertise in weather forecasting and climate monitoring allows state and federal fishery managers to make well-informed decisions using the latest observations of river levels and mountain snowpack gathered by satellites, radar, on-land and offshore systems.
To view current drought conditions, visit NOAA’s drought portal—www.drought.gov.
Home page photo of Folsom Lake's dry lake bed courtesy of the California Department of Water Resouces.