Author Archives: Tom Cannon

Splittail – Native Delta Minnow

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Splittail – Native Delta Minnow

Splitail Indices Graph

Splittail, formerly listed as threatened under the federal Endangered Species Act (1994), were delisted in 2003 after nearly a decade of wet years that brought about apparent recovery.1 Dr. Moyle’s recent warnings about other Delta native fish2 after nearly a decade of drought surely apply to splittail. Once the most abundant fish in late spring and early summer salvage collections at the south Delta export facilities, splittail are now rarely collected3. Once common in dry periods (1987-1992) and prone to abundance in wet periods (1993-2001), they are now rare in dry periods (2007-2009, 2012-2015). Because they live 5-8 years, they are able to spawn successfully in infrequent flood years, 2011 being a good example. The modest production from 2011 will be five years of age in 2016. One can only hope that 2016 will be a wet year.

I argued at a January 2001 CALFED workshop on splittail4 for retaining the listing of the species as threatened; however the consensus was “statistical power to detect real population trends in the past 30 years is low, thereby undermining confidence in any estimates of extinction risk based on abundance”. The 15 production years since the workshop have clearly added to the “statistical power”. I would argue for relisting splittail, if only for the reason they are now far less abundant then they were prior to the original listing, and to ensure something is done to protect them over the next several years so they indeed do not go extinct.

Predator Fish Control Again Rears Its Ugly Head

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The predator-control movement in the Delta got started around the turn of this century when efforts were initiated to reduce the Central Valley Striped Bass population by removing them from Clifton Court Forebay in the South Delta and by stopping the hatchery and pen rearing supplementation programs. Efforts under the Central Valley Project Improvement Act of 1992 (CVPIA), specifically the Anadromous Fish Restoration Program (AFRP), were beginning to make progress at restoring Central Valley fish populations including winter, spring, fall, and late-fall run Chinook, Steelhead, sturgeon, and Striped Bass. Of course, these efforts had been enormously aided by Mother Nature in the form of a series of wet years following the disastrous 1987-1992 drought that precipitated the CVPIA (and many of the endangered species listings).

Striped Bass supplementation had reached its apex. Hatchery raised yearlings were stocked by the millions. Millions of wild young stripers salvaged at South Delta federal and state pumps were placed in pens in the Bay and fed for one to two years and then released.

The end of the wet years and the beginning of the Pelagic Organism Decline in the early 2000s brought out “predator control” for the Central Valley. Federal and state water contractors planted the seed as their Delta diversions reached record levels of 6 million acre-ft. The first effort was to develop a predator removal program at the State Water Project’s Clifton Court Forebay in the south Delta. A further effort forced California Department of Fish and Wildlife (CDFW) to prepare a Habitat Conservation Plan (HCP) for its Striped Bass Supplementation Program (which was approved and the program continued for several years). CDFW did not undertake predator removal in the Forebay.

The 2007-2009 drought brought a water contractor sponsored lawsuit against CDFW, and when that failed, an approach to the California Fish and Game Commission to eliminate sportfishing regulation restrictions on Striped Bass. Relying on sound science, the Commission unanimously rejected their efforts.

The recent Bay Delta Conservation Plan (BDCP) included predator control at “hotspots” in the Delta. But BDCP has been cast aside in favor of Governor Brown’s “water fix.”

This past week FISHBIO Inc., a major contractor for the water districts in the Central Valley, posted “Can Predator Control Help California’s Native Fishes?”1 The post relates the passage of a bill in the House specifically regarding predator control to protect endangered species. While most (hopefully the Senate) will see the bill as part of the water contractors’ “smoke screen”, the bill exemplifies continued efforts on the part of water contractors in the Central Valley to place the blame and solution elsewhere. The post relates about a recent San Joaquin restoration program meeting where information on predators was presented. No mention was made of the recent record low flows in the San Joaquin or the fact that salmon numbers are directly related to flows, or that salmon cannot survive their migrations in the warm polluted waters of the San Joaquin in drier years.

The post mentions a modeling study that shows Striped Bass could eat all the San Joaquin salmon. However, it fails to mention the abundance of young hatchery salmon prey dumped into streams at the same time that Striped Bass and other predators are attracted into the cooler tributaries by the same warm polluted waters of the San Joaquin that block young salmon from moving to the ocean. It fails to acknowledge that upstream dams intercept the early natural pulse flows of cold water that would enable wild salmon fry to move out of the tributaries before waters warm sufficiently for predators to become active. It fails to mention that Striped Bass are also at record low levels. It fails to mention that hundreds of thousands of recovery program hatchery smolts have been dumped into the San Joaquin that serve to encourage predators to switch to salmon (these hatchery fish should be barged to and through the Delta to the Bay – an action that should be funded by the water contractors). And, for the record, it ignores the fact that aquatic life is a mutual eating society and hatchery salmon and steelhead smolts prey on wild salmon fry.

The post concludes with “This month’s actions to amend the Commerce, Justice and Science Appropriation Act may finally open the door to predator control programs in California – a hopeful step towards remedying a long-term problem that continues to spin out of control.” FISHBIO had better prepare for interviews on FOXNEWS.

(AUTHOR’S NOTE: predators including native fishes, birds, and marine mammals, as well as non-native fish like the Striped Bass and other state protected gamefish, take a huge toll on our native endangered salmon, steelhead, trout, smelt, and sturgeon. Predation is probably a primary causal factor as an indirect effect of water diversions on native fish. What is needed is a comprehensive recovery program like that on the Columbia River2. That program addresses the full spectrum predators like pikeminnow, terns, cormorants, marine mammals, and even non-native shad, stripers, smallmouth, walleye, and northern pike. However, unlike California erratic efforts to manage fisheries, the Columbia success-story, at least to date, can be attributed to progressive water management and hatchery-wild fish, science-based, recovery programs.)

Summer 2015 Temporary Urgency Change Petition: Deadly for Delta Smelt

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What does the May 21 TUCP mean for the Delta if the State Board adopts it for the summer? What would be the consequences of weakening the outdated standards for outflow and salinity do to the Bay-Delta ecosystem?

letter

Location of X2 and Delta Outflow

The location of X2, the critical location of the Low Salinity Zone center where salinity is 2 parts per thousand (ppt), is shown below for various Net Delta Outflow Indices (NDOI). The existing standards and proposed changes are as follows:

  • 4000 cfs NDOI in July – 3000 cfs proposed
  • 3000 cfs NDOI August – 2500 cfs proposed for September
  • X2 (2.78 mmhoes EC) required at Emmaton (EMM) moved upstream to Threemile Slough (TMS) through August 15 (no limit thereafter)
Location of X2 in Bay-Delta at various Delta outflows (NDOI cfs).

Location of X2 in Bay-Delta at various Delta outflows (NDOI cfs).

Effect on Water Temperature

In June weakened standards from a previous TUCP were 4000 cfs NDOI, with X2 allowed at TMS. Water temperature at X2 location by mid-June reached 70-73°F, levels considered sublethal but stressful on Delta Smelt.

stressful on Delta Smelt. Early June 2015 water temperatures in X2 region.

Early June 2015 water temperatures in X2 region.

On June 12, 2015, X2 reached Rio Vista Bridge (for first time this year) on high tide after midnight at 72°F (NDOI was 5200 cfs). Afternoon water temperatures at bridge at low tide had been >74°F. When EC was 2000 at TMS, the water temperature was 72°F. On this date in 2012, the X2 location was downstream of EMM, with an NDOI of 7100 cfs and a water temperature of 69°F. On this date in 2013, X2 was downstream of EMM, with an NDOI of 7500 cfs and a water temperature of 68°F. On this date in 2014, X2 was upstream of EMM, with an NDOI of 3150 cfs and a water temperature of 72°F. The pattern is consistent with the hypothesis that the further X2 is east, the warmer the water temperature will be. The pattern also indicates that the normal standard of 7100 cfs keeps water temperatures at X2 below 70°F, at least in late spring.

My prediction for water temperature for July through September in the X2 region is shown below. This conservative prediction is based on June 2015 and June-September 2014 data.

Predicted summer water temperatures in X2 region of the Delta under proposed weakened standards.

Predicted summer water temperatures in X2 region of the Delta under proposed weakened standards.

Consequences to Smelt and Salmon

Delta Smelt, already on the brink of extinction, will be further stressed by near lethal water temperatures in the X2 region. We can assume that only a small number of smelt remain in the X2 zone going into summer 2015, as compared to 2012 (see following charts). Any remaining smelt in the X2 zone must be protected at least at the normal standards as in 2012. Any weakening of the critical year standards will jeopardize the existence of the species.

No Delta Smelt were collected from the X2 zone in late May 2015. Only 5 were collected at the northern Deep Water Ship C

No Delta Smelt were collected from the X2 zone in late May 2015. Only 5 were collected at the northern Deep Water Ship Channel station.”

In contrast to 2015, the distribution of Delta Smelt in late spring 2012 shows higher numbers collected in the X2 zone below Emmaton under NDOIs of 8000-10,000 cfs. Water temperatures at that time in the X2 zone were <70°F.


In contrast to 2015, the distribution of Delta Smelt in late spring 2012 shows higher numbers collected in the X2 zone below Emmaton under NDOIs of 8000-10,000 cfs. Water temperatures at that time in the X2 zone were <70°F.

Fall Run Chinook Salmon enter the Bay-Delta on their spawning migrations from the ocean in August-September. Expected near -lethal water temperature (>77°F) will delay and stress these fish. Expected water temperatures greater than 70°F will stop migrations and degrade subsequent adult salmon pre-spawn survival and egg viability. The proposed 2500 cfs outflow standard for September will result in water temperatures of 73-75°F in the X2 zone near Rio Vista in mid-September. In contrast, in mid -September 2012, outflow was 7100 cfs and water temperatures at Rio Vista and the X2 zone near Emmaton were <70°F.

Are Winter and Spring Run Salmon being protected below Shasta? Absolutely Not!

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By now it is common knowledge that 95% of last year’s endangered Winter Run Chinook salmon production in Sacramento River below Shasta-Keswick Dams was lost due to low flows and high water temperatures in summer. Large losses also occurred to Spring Run and Fall Run salmon. As they did last year, the US Fish and Wildlife Service, National Marine Fisheries Service, US Bureau of Reclamation, California Department of Fish and Wildlife, and California State Water Resources Control Board are managing water releases from Shasta Reservoir to ensure flows and water temperatures are adequate for Spring Run and Winter Run salmon spawning adults and eggs and alevins in gravel beds. This year they all assured us they had adequate water and cold water pool to maintain flow and cool water temperatures to protect the salmon in the upper spawning reach near Redding. They acknowledged there was insufficient water to protect the lower spawning reach below Redding (down to Red Bluff).

Already two months into the irrigation season and after a quarter million acre-feet of water released to water contractors (about 10% of Shasta storage and 25% of the cold water pool), Reclamation has determined they overestimated the available amount of cold water pool and their ability to maintain flow and water temperatures for salmon into the fall. Fearing the worst, storage releases have been reduced, and protective water temperature limits in the Redding spawning reach have been raised to conserve the cold water pool.

We only have to look at the State Board’s own science review of water temperature effects on salmon1  to see if water management in the spawning reach is protecting salmon.

  1. Mean Weekly Maximum Water Temperature (MWMT) should not exceed 13C (55.4F) – generally referred to as 56°F limit.
    1. Keswick Dam releases have been slightly higher than 56°F MWMT.
    2. Sacramento River compliance point above Clear Creek has MWMT of 60°F.
    3. Clear Creek upstream of mouth has a MWMT greater than 60°F.
    4. Sacramento River below Clear Creek at Anderson has MWMT OF 62°F.
  2. Daily maximum water temperature should not exceed 13.5-14.5°C (56-58°F) from fertilization through fry development.
    1. Keswick releases have reached 56°F.
    2. Sacramento River at compliance point above Clear Creek has reached 60.7°F.
    3. Sacramento River below Clear Creek at Anderson has reached 62°F.
  3. Optimal temperatures for egg incubation is <13°C (55°F).
    1. Exceeded throughout spawning reach.
  4. Water temperature when pre-spawning mortality of adult Chinook becomes pronounced in ripe adult salmon – 13-15.5°C (55-60°F)
    1. Exceeded throughout spawning reach.

Obviously the 56-60°F maximum daily water temperatures in the primary spawning reach above the mouth of Clear Creek at Redding are a concern. The State Board has raised compliance from 56°F to 58°F in attempt to conserve cool water through the summer. They have also reduced allowed Keswick releases from 8000-9000 cfs to 7500 cfs for the summer to save storage and the cold water pool. Reclamation is keeping Keswick releases near 7000 cfs.

Our concern is for pre-spawn ripe adult mortality and egg viability, as well as egg viability and embryo survival in redds. The agencies seem to think maximum daily temperatures near 60°F are ok, when they are not. Destroying this year’s egg production before the cold water pool is exhausted should not be the approach. Maximum temperatures should not exceed 56°F above Clear Creek. A maximum temperature of 58°F should be the absolute limit.

Far more important is the water temperatures in the redds, which tend to occur in shallow pool tailouts that are often warmer than average river temperatures. There must be a margin of protection for this difference. Redd temperatures should also be carefully monitored.

Clear Creek at Redding Tempratures

Hatchery Reform – Part 4

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Previously… Part 1: Central Valley Salmon and Steelhead Hatchery Program Reform, Part 2: Hatchery Reform, & Part 3: Hatchery Reform

Golden Gate Salmon Association (GGS) Project D.3 Improve Trucking Techniques for Hatchery Salmon Background and Scientific Analysis December 4, 20131

The goal of this project is to improve trucking results especially at the Federal Coleman Hatchery on Battle Creek where there are poor hatchery returns and high straying rates from trucking… The survival of trucked and acclimated fish was substantially higher than that of fish released at the hatchery basin. The combined average trucking improvement from all the hatcheries was 3.49 to 1. The improvements ranged from a high of 71 to 1 at the Feather River hatchery to a low of 1.8 to 1 at Coleman. These figures mean trucking produces many thousands of additional adults for harvest or for return. But, the returns are still very low when compared to the losses that are avoided by trucking the fish around the rivers and the Delta. Studies of the mortality of juveniles migrating down the Sacramento River and through the Delta range up to 90%. Avoiding this loss indicates that the survival of trucked fish should be more in the order of 10 to 1 over basin released fish. Current science cannot explain this difference. More research is needed.

Clearly, their Exhibit 1 below depicts the benefits of trucking in avoiding the many risks in the up to 200 mile trip to the Ocean for Central Valley salmon. Trucking bypasses much of risk, but results in high straying rates. As described previously, barging and out-planting offer potential reduction in straying without giving up the huge advantage in survival and production.

Exhibit 1

Smolt Production from hatchery adults. Kathryn E. Kostow , Anne R. Marshall and Stevan R. Phelps. 2011.2 Naturally Spawning Hatchery Steelhead Contribute to Smolt Production but Experience Low Reproductive Success

Our data support a conclusion that hatchery summer steelhead adults and their offspring contribute to wild winter steelhead population declines through competition for spawning and rearing habitats.

There is considerable scientific study that indicates that the offspring of hatchery salmon and steelhead have lower reproductive success than wild native fish. Wild native fish have many general and locally adapted traits that are often missing in hatchery fish. For Central Valley salmon and steelhead, many of these native traits were lost long ago. Tribes in northern California hope to bring some traits back from wild salmon sent from California to New Zealand a hundred years ago. Recently, special traits involving greater growth and longevity of Lahontan Cutthroat Trout were restored to Pyramid Lake in Nevada from an outside source.

In the end, we can only hope that restored “wild” populations will begin the natural selection process in restoring traits that contribute to higher survival and production. At minimum, hatcheries should discontinue practices that degrade natural diversity and genetic inheritance, and should focus on improving diversity and traits that enhance the ability to survive Valley conditions now and in the future.