“Epic” Salmon Fishing this Summer

Reports on the July 15 opener on the lower Sacramento fall-run salmon season are good.1 Reclamation and Sacramento River farmers have provided the flows needed to keep water temperatures down (Figure 1), allowing what appears to be a good run up the river from the Golden Gate. Openers in recent years have been poor because of low flows and high water temperatures, as well as low salmon numbers. Numbers are up, and water temperatures are down – good for fishing.

Figure 1. Higher flows in July have cooled the river despite many 100+ degree days. Source.

Sacramento Valley Salmon Resiliency Strategy

The Sacramento Valley Salmon Resiliency Strategy, June 2017, is the state’s strategy to improve the resilience of listed salmon to its activities, including water rights permits, State Water Project actions, CESA implementation, and CDFW management.

The document states on page 2:

Specific biological objectives have been identified for the Sacramento River that support the general need to increase survival and productivity of salmonids in the Sacramento Valley and to increase life history and genetic diversity. A summary of these biological objectives:

  1. Increase productivity by improving spawning and incubation conditions (habitat and water quality).
  2. Increase productivity by increasing juvenile salmonid survival.
  3. Support the full range of juvenile migration conditions to maintain life history diversity.
  4. Support the full range of adult migration conditions to maintain life history diversity.
  5. Maintain genetic integrity by limiting genetic influence from hatchery-produced fish and interbreeding of genetically or behaviorally distinct runs.

The Strategy is an aggressive approach to improving species viability and resiliency by implementing specific habitat restoration actions. (Emphasis and bullet numbering added)

The Strategy is defined as a “resiliency” strategy and not a recovery strategy for a reason. It does not include the actions necessary for recovery. It won’t fix the activities that caused the crisis in the first place. Over the past several decades, much restoration has occurred, yet fish populations continue to decline. Much stronger and more immediate management actions are needed to save the salmon populations. Habitat restoration alone will simply not suffice.

So what is missing?

  1. Spawning and incubation conditions – Missing are actions to maintain cold water temperatures and sufficient spawning flows in the reaches below all the major dams during spawning and incubation. A. Eliminate the water temperature increases caused when water from Whiskeytown Reservoir is routed through Spring Creek Powerhouse to Keswick Reservoir. B. Maintain cold water in the Sacramento River downstream to Red Bluff, not just to Redding. C. Eliminate dewatering of winter, spring, and fall–run salmon redds in the Sacramento River. D. For the American and Feather rivers, take actions similar to A through C that maintain cold water and eliminate redd stranding. E. Better manage reservoirs to place more emphasis on cold water pools and less on water deliveries.
  2. Juvenile salmon survival – Maintain adequate flows and water temperatures in rearing reaches to sustain growth and to reduce stress and predation.
  3. Full range of juvenile migration conditions – Maintain adequate flows and water temperatures in the lower rivers and the Delta throughout emigration seasons. Do not shave off early and late seasons.
  4. Adult migrations – Maintain adequate flows and water temperatures to assure adult survival, egg survival and gonad development during migration. Do not shave off early and late seasons.
  5. Genetic integrity – Move more toward conservation hatchery activities, reduce straying by barging smolts, implement natural floodplain rearing, mark all hatchery smolts, and introduce mark-selective recreational fisheries.

As for other planned actions like completing projects on Battle Creek and reintroducing salmon upstream of Central Valley rim reservoirs, let’s get on with it. If we keep the present snail’s pace, there is little hope for future salmon generations.

Would WaterFix Tunnel Intakes be Protective of North Delta Fish? You Judge!

The Department of Water Resources’ consultant on in the WaterFix tunnels hearing testified:

“But for those Smelts that are occurring in that area, the North Delta diversions will be designed to fish agency protective standards”… “That opening, based on analyses, would prevent entrainment of Smelts that are greater than about 21 to 22 millimeters.”1

“In the EIR/EIS, the only significant and unavoidable impact that we found was for Striped Bass and American Shad. This is because of entrainment of early life stages at the North Delta diversions. These are species that spawn upstream of the North Delta diversions, in large part…..2

For American Shad, studies suggest that many American Shad were upstream of the Delta and, therefore, when they’re coming down into the Delta, they would be sufficiently large to be screened by the North Delta diversions.”

Delta Smelt

Delta smelt spawn in the north Delta in late winter and early spring. Their juveniles occur through summer. Their young would be highly susceptible to entrainment throughout spring (Figure 1).

White Sturgeon

Sturgeon, both green and white, spawn above the Delta in the lower Sacramento River in early spring. Their larvae and early juvenile stages reach the Delta in spring at a size highly vulnerable to entrainment (Figure 2).

American Shad

American shad spawn in the lower Sacramento River and tributaries in late spring and summer. Their larvae and early juveniles are prevalent in the north Delta in late spring and would be highly vulnerable to entrainment (Figure 3).

Striped Bass

Striped bass spawn predominantly in the lower Sacramento River in spring. Their larvae reach the north Delta in May and June, and would be highly vulnerable to entrainment (Figure 4).

Splittail

Splittail spawn in the lower Sacramento River floodplain in spring. Their early juveniles reach the north Delta usually in May and would be highly vulnerable to entrainment (Figure 5).

Prickly Sculpin

Prickly sculpin, an abundant native Delta fish, spawn in the lower Sacramento River in late winter and their larvae are found in the north Delta in early spring and would be highly vulnerable to entrainment (Figure 6).

Sacramento Sucker

Sacramento sucker spawn in Valley rivers in spring. Their larvae and early juveniles are present in the north Delta throughout spring and would be highly vulnerable to entrainment (Figure 7).

Threadfin Shad

Non-native threadfin shad, the most abundant forage fish in the Delta, spawn from late spring into summer throughout the Delta and lower rivers. Their larvae and early juveniles are prevalent in the north Delta in late spring and early summer, and would be highly vulnerable to entrainment (Figure 8).

Summary and Conclusions

Larval and early juvenile lifestages of many Delta fishes would be highly vulnerable to entrainment through the screens of the proposed WaterFix north Delta intakes. Juvenile/fry of these and other species (salmon3) would be highly vulnerable to impingement and predation at the screens.

Figure 1. Length frequency of Delta smelt captured in the California Department Fish and Wildlife’s annual Delta-wide 20-mm Survey. For each sub-graph within this figure and each of the following figures, the x-axis shows the length in millimeters of captured fish, and y-axis shows the number of captured fish of each length. Note that most of the early spring post-spawn larvae and juveniles are of a size highly vulnerable to entrainment (<20 mm).

Figure 2. Length frequency of white sturgeon captured in the 20-mm Survey . Note larval sturgeon were captured soon after their spawning period in spring at a highly vulnerable size to entrainment. Many larvae of the main lower Sacramento River population of white sturgeon would pass the proposed WaterFix intakes.

Figure 3. Length frequency of American shad captured in the 20-mm Survey . Note that most of the shad would have to pass the proposed north Delta intakes in spring at a size highly vulnerable to entrainment (<20 mm).

Figure 4. Length frequency of striped bass captured in the 20-mm Survey . Note that most of these striped bass larvae would have had to pass the area of the proposed north Delta WaterFix intakes at a size would be highly vulnerable to entrainment (<20 mm).

Figure 5. Length frequency of splittail captured in the 20-mm Survey Note that many splittail spawn in the Sacramento Valley floodplain just upstream of the proposed north Delta WaterFix intakes, and that many of the juvenile splittail emigrating back to the Delta would pass the proposed WaterFix intakes at a size vulnerable to entrainment (<20 mm).

Figure 6. Length frequency of prickly sculpin captured in the 20-mm Survey . Note that the larvae of winter-spring spawning sculpin would be highly vulnerable to entrainment (<20 mm).

Figure 7. Length frequency of native Sacramento sucker captured in the 20-mm Survey . Note that the juveniles of late winter-early spring river spawning suckers return to the Delta at a size vulnerable to entrainment (<20 mm).

Figure 8. Length frequency of threadfin shad captured in the 20-mm Survey . Note the late spring-early summer spawning threadfin shad are highly vulnerable to entrainment (<20 mm).

  1. WaterFix hearing transcript, 2/23/18, Page 124, line 2:  Dr. Greenwood testimony at State Board WaterFix hearing.
  2. Id., Page 156, line 6.  Note that many shad and striped bass spawn their buoyant eggs in the area of the proposed intakes and immediately upstream, as well as in the lower Feather, Sacramento, and American rivers.  Nearly all the eggs and newly hatched larvae would pass the proposed CWF intakes.
  3. Much of the wild salmon production from the American and Feather rivers’ fall-run populations comes from fry (30-50 mm) leaving these rivers in winter.  Winter is the peak period of proposed north Delta diversions of the WaterFix project.  These fry would not be protected by the proposed WaterFix screens.