By now most everyone has seen the newspaper articles on the catastrophic decline in Winter Run Chinook salmon production in the Sacramento River below Shasta Reservoir in 2015. The number of Winter Run juveniles passing downstream past Red Bluff is down substantially from last year, when the estimated survival rate was 5%. Many blame the drought – the fourth year of drought. I have blamed poor water management and the weakening of water quality standards prescribed to protect the salmon (see previous posts).
It is now time for extreme actions to save these fish. This coming year’s winter adult run will be made up primarily of the 2013 spawn, with some from 2012. These spawns were marginally successful and could produce enough spawners next summer to help fix this debacle.
The responsible agencies plan to take more eggs and increase smolt production at the Livingston Stone Hatchery near Redding. They also plan to truck these hatchery smolts to the Bay to maximize their survival. They will likely severely limit commercial and recreational fisheries that may harvest Winter Run. They plan to again start raising a rescue population in captivity to ensure they have some fish in the future to draw on for recovery. A new drought plan will again address how flows and water temperatures will be managed below Shasta. The State Board may resist weakening Sacramento River and Delta water quality standards designed to protect Winter Run, unlike what they did in the last two years. All of these actions together will indeed help Winter Run from further decline, but it will not be enough even if the El Niño brings abundant rain and snow.
What else? The answer to that question should be everything that is reasonably possible to increase production and survival. Here are some suggestions:
- Do not weaken Sacramento River and Delta water quality standards that protect Winter Run. (This alone would have averted the catastrophes below Shasta the past two years.)
- Minimize warm water inputs to the Sacramento River in summer from the Trinity River to keep Sacramento River temperatures lower and save Shasta’s cold-water pool.
- Alter peaking hydropower management and system infrastructure in Shasta-Trinity CVP system to improve water temperatures in the Sacramento River and the conservation of reservoir cold-water pools.
- Further limit Shasta-Trinity reservoir releases to water contractors to conserve cold-water pools and maintain flow requirements for salmon.
- Enhance natural winter and spring flow pulses from tributaries below Shasta with flow releases from Shasta to increase survival of emigrating wild juvenile salmon migrating downstream in the Sacramento River, to and through the Delta, and to and through the Bay to the ocean.
- Conduct an aggressive rescue program of adult Winter Run that migrate into Sacramento Valley bypasses only to be blocked below overflow weirs, or that migrate into dead-end basins, or that stray into other tributaries including Battle Creek, Feather River, and American River salmon hatcheries.
- Capture wild juvenile Winter Run in an enhanced trapping program at fish screen bypasses, screw traps, and other techniques in the Sacramento River in fall and winter migration period, and transport these juveniles to the Bay to avoid lower river and Delta sources of mortality.
- Modify Delta operations to maximize juvenile Winter Run survival through the Delta. This may involve further changes to Delta Cross Channel operations and Delta export schedules, as well as Delta inflow and outflow.
- Maximize egg taking and rearing capacity in hatchery system.
- Barge wild and hatchery young from the Sacramento River through the Delta for release in the Bay to avoid future straying problems associated with trucking fish.
- Raise juvenile hatchery salmon in floodplain habitats in winter in the Sacramento Valley (e.g., Sutter and Yolo Bypasses).
- Conduct egg injection or fry releases in appropriate locations in Battle Creek to jumpstart its prescribed new population; this can be managed at the Battle Creek hatchery.
- Develop and implement an emergency comprehensive plan with appropriate agencies with the necessary authority to carry out these actions. Include stakeholders in the plan development and review process. Obtain necessary funding from available sources.