Are Delta Smelt Starving?

Posted on October 7, 2016 by Tom Cannon

The Sacramento Bee reported on August 31, 2016 that Dr. Ted Sommer at the California Department of Water Resources says that Delta smelt are starving. Dr. Sommer related recent success in stimulating the north Delta food web (Figure 1) by increasing flow through the Yolo Bypass in July as part of the state’s new strategy to help Delta smelt. I had reported earlier on the experiment and the strategy.

While Dr. Sommer was not implying that just adding some fertilizer to the north Delta would save the smelt, he was deflecting discussion and treatment away from the overriding cause of the collapse of Delta smelt: lack of spring-through-fall outflow to the Bay.

During August of this year, the normal heavy hand of Delta exports again reached out to degrade the critical habitat of what few smelt are left (Figure 2). In summer, Delta smelt concentrate near X2, the area of the estuary where brackish water of about 2 ppt salinity occurs. Food concentrates at X2, as shown in Figures 3 and 4. Chlorophyll levels at X2 are an order of magnitude higher than at Rio Vista (Figure 1), where Dr. Sommer observed the increase in chlorophyll from the recent experiment.

X2 also has cooler water temperatures and higher turbidities preferred by smelt (Figures 5 and 6). It is at X2 where smelt are meant to be so they do not starve, do not get eaten, and do not die from high water temperatures. The problem is that X2 habitat readily degrades when summer outflow is low (4000 cfs) and exports are high (11,200 cfs). Under these conditions, low-salinity habitat and food (plankton) are siphoned off with each tide into False River, into Dutch Slough, and further upstream into the San Joaquin River channel (also shown in Figure 2).

Smelt did fine in summer 2011, the year with the last decent fall smelt index. X2 was much further downstream, and Delta outflows were high (15,000 cfs). If X2 stays out of the Delta, and smelt can get to X2 and stay there, they and their food supply will be far better off. This requires about8,000-10,000 cfs outflow in July and 6,000-8,000 cfs outflow in August. The present 4,000 cfs outflow index (real outflow, as opposed to the index, is closer to zero – see Figure 2), while exports are11,200 cfs just does not meet their needs.

Figure 1. Chlorophyll concentrations at Rio Vista in the north Delta July 23 to August 31, 2016.

Figure 2. Net Delta hydrology (flow in cfs) on August 25/26 during a spring tide. Net Delta outflow is near zero with positive net flow in the Sacramento channel (north) and negative net flows in the San Joaquin channel (south). Exports were near maximum at 11,200 cfs. The location of X2 (2 ppt salt) at high tide is shown as magenta line.

Figure 3. Chlorophyll concentrations in summer 2016 at Blind Point in the lower San Joaquin channel (magenta line in Figure 2). Red circles denote periods when X2 moved upstream to Blind Point.

Figure 4. Salinity in summer 2016 at Blind Point in the lower San Joaquin channel (magenta line in Figure 2). Red circles denote periods when X2 approached Blind Point.

Figure 5. Water temperature in summer 2016 at Blind Point in the lower San Joaquin channel (magenta line in Figure 2). Red circles denote periods when X2 approached Blind Point.

Figure 6. Turbidity at Blind Point in the lower San Joaquin channel (magenta line in Figure 2). Red circles denote periods when X2 approached Blind Point.

Figure 7. Concentrations of Delta smelt in the Summer Townet Survey July 2011. Magenta line is location of X2.

Predation

Posted on September 24, 2016 by Tom Cannon

“While state and federal wildlife agencies, university researchers, and water users all agree that predation from non-native fishes is a major stressor on salmon populations, we have done nothing to try to directly curb its impact.”

This statement in a recent Fishbio blog post is simply not true.

In 1995, the state removed limits on summer Delta exports that had been in place for decades to protect young striped bass. Stocking of striped bass ended at the beginning of this century. Both actions contributed to record low production of striped bass over the past decade. ¹ The Bay-Delta population of striped bass is now greatly depressed. The river population is sustained by the continuing policy of releasing hatchery salmon smolts in the spring at the hatcheries, an unnatural process that simply feeds the river stripers.²

The real problem is spring water management in the Sacramento and San Joaquin rivers that brings unnaturally low flows and warm, clear water that favors the predators. All the salmon runs naturally have juveniles migrating to the Bay in high cold flows from late fall to early spring when predators are inactive and ineffective. But with dams holding the water from winter rains and snows, the rivers lack natural winter flows and spring snowmelt.

Largemouth bass production in the Delta has increased because of habitat changes from water management, droughts, and invasive aquatic plants that have turned the Delta into an “Arkansas lake.” Smallmouth bass production has increased in the rivers with lower, warmer flow conditions from spring through fall.³

The native pikeminnow also benefit from the habitat changes in the rivers and Delta, as well as the abundance of spring hatchery smolts. Huge schools migrate from the Delta into the rivers in spring and summer to spawn. The tailwaters downstream of dams favor pikeminnow. The adults feed on young salmonids and the juveniles compete with juvenile salmonids. Juvenile pikeminnow that return to the Delta feed on smelt.

It is these habitat changes that have resulted in more effective predation on native salmon, steelhead, and smelts. Ignoring the cause won’t solve the problem. Focusing on the predators will not work. The basses and native pikeminnow have prolific reproductive systems. Killing more of them by removing regulations on their harvest or even putting bounties on them (like pikeminnow on the Columbia River) will not solve the root problem – habitat change. And without the predators, what would be left to control all the non-native forage and “trash-fish” that already plague the Delta and rivers?

In the future, if we continue to take more of the river flows and further degrade habitats, there will always be the temptation and the drumbeat to directly remove predators or inhibit their migrations. We can stop salvaging millions of these predators every year at the South Delta export facilities, stop returning all the bass caught in fishing tournaments, and truck all the remaining salmon produced only in hatcheries to the Bay. In the end we will still have abundant predators, an “Arkansas-like lake,” hatchery salmon, and at best novelty populations of endangered wild salmon, steelhead, sturgeon, smelts, complemented by likely newly listed species of native fishes like splittail, blackfish, hitch, etc.

Smallmouth Bass Expansion (Hypothesized)

Posted on September 21, 2016 by Tom Cannon

One of the major salmon predators on the Columbia River is the smallmouth bass. Long protected because of its contribution to a highly popular sport fishery, that protection is now gone because of the predation threat to Columbia River salmon recovery. Smallmouth and walleye are highly regarded game fish, but are not native to the Columbia River. They compete with and prey upon salmon. The Columbia states recognized this and no longer regulate these fisheries. This change will help prevent expansion of these species as global warming provides more favorable conditions for these cool-water non-natives than for the cold-water salmon, sturgeon, and steelhead.

Smallmouth bass have long been present in the Central Valley, especially in the lower Sacramento River and the rim dam reservoirs. Recent changes in the management of water in the lower Sacramento River will accelerate expansion of smallmouth and their preferred habitats over that of global warming alone. Smallmouth have historically been constrained by Basin Plan’s 56°F water temperature limit at Hamilton City (or Red Bluff) and the 68°F limit below Hamilton City to the Delta. However, smallmouth are highly likely to expand their population and range in the lower Sacramento River due to recent changes in flow management strategies that provide lower flows, warmer waters, and less turbidity to nearly 200 miles of the lower Sacramento River.

Ironically, the strategy changes meant to save water and cold-water reservoir supplies for salmon will actually benefit smallmouth, a key predator on salmon. The changes have already benefitted striped bass by enhancing their opportunities for predation. ¹ An expansion of the smallmouth population is now likely because of warmer spring water temperatures (Figures 1 and 2) caused by lower river flows in the spring (Figure 3). The more days water temperatures exceed 60°F, the more successful spring breeding and survival of smallmouth will be. ²

Removing fishery protections will not solve the potential population enhancement or predation problems of smallmouth in the Central Valley. It would be a purely symbolic measure because smallmouth are so abundant and widely distributed. It is limitations on their habitat that have held back their expansion and the impact of their predation on salmonids. With the habitat limitations lessening, the smallmouth population will expand and contribute more to the predation problem. The solution is to restore former habitat limitation on smallmouth by sticking to the Basin Plan standards.

For more on smallmouth life history see this excellent YouTube video: https://www.youtube.com/watch?v=hoZ81au_YZg. Note in the video the strategy of smallmouth feeding heavily in the fall on small fish to store energy for the coming winter. Fall is when the winter-run salmon juveniles produced over the summer start their 200-mile downstream journey from the upper river spawning grounds to the Bay. All 200 miles have smallmouth bass.

Figure 1. Water temperature in Sacramento River at Red Bluff (RM 243) in spring 2016. Red line depicts Basin Plan limit of 56°F for river at Red Bluff.

Figure 2. Water temperature in Sacramento River at Wilkins Slough (RM 125) in spring 2016. Red line depicts Basin Plan limit of 68°F for lower river.

Figure 3. Sacramento River daily flow for years 2008 to June 2016. Red line depicts normal flow of 5000 cfs. Circles depict the tendencies for lower flows in recent years including spring 2016.

My comments on: “SLDMWA Response to Environmentalists’ August 9, 2016 Request to the SWRCB for Even More Water Aimed at Protecting Delta Smelt”

Posted on September 15, 2016 by Tom Cannon

On August 11, Jason Peltier, executive director of the San Luis-Delta Mendota Water Authority, offered comments on a letter from environmental groups to the State Board that requested more water for Delta Smelt. Below, I provide some of Mr. Peltier’s statements, and a response to each:

1. “As environmental special interests request the State Water Resources Control Board expand failed policies on Delta Smelt, Californians are calling on the Board to implement new science-based, common sense approaches to protect the species. It is disheartening to see once credible environmental organizations calling for a “more of the same” approach – one that has so miserably failed for a quarter century – in a misguided attempt to help the imperiled delta smelt.”

Comment: The environmental organizations were proposing what the state has also offered as its new strategy for the Delta Smelt. It is not the old misguided “failed” strategy of diverting more and more water and providing less and less Delta outflow to the Bay. The state’s new strategy derives from some of the same actions suggested in this past April’s science workshop on Delta Smelt held at UC Davis, which Mr. Peltier attended.

2. “[t]he Projects have compensated for Mother Nature’s stinginess with water released from reservoirs, making the Delta far fresher than it would have been naturally.”

Fact: Just the “natural” summer inflow to Shasta Reservoir in the past four years of drought nearly equaled the amount allocated for summer Delta outflow. If you add up all the Central Valley’s “natural” inflow it would far exceed the Delta outflow allotted, even without accounting for use above the rim reservoirs.

3. “This dedication of water for fish from what was stored for drought relief has resulted in unprecedented socio-economic and environmental harms to towns, farms, and numerous species living in the largest wetlands in the West.”

Fact: Most of the water stored is for agriculture and released for agriculture. Mr. Peltier’s organization is simply last in line for stored water and thus gets less water allocated during droughts. In June and July, nearly 30,000 cfs of water was released on average from Central Valley reservoirs, but only 7000-8000 cfs reached the Bay to repel salt intrusion. Because Shasta releases were reduced to protect salmon (not smelt), Mr. Peltier’s organization was unable to receive more than a minimal allocation. Again, this is because its water rights are junior to those of other users, not because of water allocated to smelt (none).

4. “Since the most severe cuts were imposed on the Projects nine years ago, less water has been diverted, and thus more Projects’ water has gone out to the ocean, than at any other time in the past 35 years.”

Fact: Seven of the last nine years were drought years. The only water consistently reaching the ocean in large amounts during those seven years was uncontrolled river flows and reservoir spills during and after sporadic winter storms. The only reservoir water that reached the ocean (Bay) in those seven dry years was the water necessary to hold back salt intrusion into the Delta so Delta diversions and exports remained possible.

5. “Farmers, fishermen, and environmentalists – everyone that truly cares about the status of our imperiled fisheries – should be furious.”

Comment: The fishermen and environmentalists are “furious” because of government mismanagement of the Shasta Reservoir cold water pool that has nearly wiped out the Sacramento salmon runs, and because of the weakening of Delta water quality standards in 2014 and 2015 that allowed excess salt into the Delta and just about exterminated the Delta smelt population.

6. “Decades old state and federal policies have failed and brought delta smelt and salmon to the brink of extinction. The last thing we need is more of the same.”

Comment: Yes, decades-old policies of increasing exports from the Delta has brought near-extinctions. It started with the massive State Water Project that came on line in the 1970’s. Yes, the last thing we need is “more of the same” – increasing exports promised with the WaterFix.

7. “Like delta smelt, we need shelter, we need food, and we need safety from predators, toxics, and invasion. The state and federal regulatory agencies have ignored for far too long the full needs of delta smelt, only willing to do what is easy, and we have all suffered for it.”

Fact: Delta smelt need the cool, brackish, wind-blown turbid waters of Suisun Bay provided when Delta outflow is sufficient to keep the low salinity zone out of the warm, confined channels of the Delta and away from its massive export pumps.

8. “We can continue to ignore decades of sound scientific advice, or we can embark on a bold new initiative, one that is transparent and inclusive of stakeholders working with state and federal agencies to save delta smelt.”

Comment: We have ignored the scientific advice. It has always been there. What “bold new initiative?”

9. “Now is not the time for desperate action, it is the time for thoughtful action.”

Fact: Giving the Delta Smelt 1000 or 2000 cfs in June and July this year – instead of nothing (Delta outflow was allocated to repel salt) – would entail only 3-6% of the water released from reservoirs and 5-10% of Delta inflow. After all, the Delta Reform Act of 2009 mandates that the state must implement the “co-equal” goals of providing a reliable water supply and protecting, restoring and enhancing the Delta ecosystem.

American River Salmon and Steelhead

Posted on September 10, 2016 by Tom Cannon

Sacrificed and Unprotected

Where are the newspaper articles about the American River “trout?”¹ Water supplies and fish are suffering all across the Central Valley, but there is no mention of American River salmon and steelhead being sacrificed so that southern California reservoirs can be filled.

The Santa Clarita Valley Signal reported on August 31, 2016:

“Castaic Lake’s water levels increased due to a rainfall and snowpack in Northern California. Castaic Lake is part of the California State Water Project and is maintained by the California Department of Water Resources as one of the state’s 34 storage facilities. Water collected by the agency is moved around the state to provide drinking and agricultural water to two-thirds of California’s inhabitants. On average, Castaic Lake holds 264,908 acre-feet of water during this time each year. It is currently holding 241,689 acre-feet of water, which is 120,467 acre-feet more than the lake was holding this day in 2015.” ²

Yes, Southern California reservoirs are being filled at the expense of northern California reservoirs (Figure 1). Folsom Reservoir in particular was drained of over half its water over the summer, which has put this year’s steelhead and salmon spawns at great risk, not to mention future water supply and hydroelectric production needed by the Sacramento region.

Figure 1. Reservoir levels in acre-feet of storage from May-August 2016.

While regional water districts are screaming foul about the declining level of storage in Folsom and San Luis reservoirs, no one seems concerned about the American’s salmon and steelhead. We can understand (but not accept) the sacrifices in the extremes of the 2012-2015 drought (Figure 2), but not in 2016 a normal water year for the American River (Figure 3). Because Reclamation has drawn down Folsom Reservoir too far even in 2016, it lost the ability to use the available cold-water pool to maintain downstream cool river water temperatures (Figure 4). Also because Reclamation drew down the reservoir level, it allowed a provision for extreme conditions to kick in: an allowed increase in the water temperature requirement from 65°F to 68°F at Watt Avenue (Figure 5). That change in the federal biological opinion for operation of Folsom Reservoir (Figure 6) is designed for extraordinary circumstances and should not have occurred in 2016.

Reclamation has also made little progress toward other requirements to fix the Folsom problem (as shown in Figure 7).

After four years of drought and the mismanagement of Folsom Reservoir this summer by Reclamation, we can expect greatly reduced natural production of salmon and steelhead from the American River in the coming years.

For more information on this subject check out: http://www.safca.org/protection/NR_Documents/LARTF_2014_09_ Folsom_TCD_VPD_Ghoring.pdf .

Figure 2. Water temperature in the American River at William Pond Park at the downstream end of the river’s spawning reach in 2015. Red lines depict water temperature objectives set for salmon and steelhead spawning and rearing.

Figure 3. Water temperature in the American River at William Pond Park at the downstream end of the river’s spawning reach in 2016. Red lines depict water temperature objectives set for salmon and steelhead spawning and rearing.

Figure 4. Water temperature of water released from Folsom Reservoir April-August 2016. Red line is maximum temperature objective. Note July 13 attempt to release water from lower colder-water level outlet.

colder-water level outlet. Figure 5. Water temperature in the American River at Watt Avenue in 2016. Green line is normal objective. Red line is relaxed standard for drought years.

Figure 5. Water temperature in the American River at Watt Avenue in 2016. Green line is normal objective. Red line is relaxed standard for drought years.