Category Archives: Steelhead

Stanislaus Trout (Steelhead)

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An August 18, 2016 article in the Calaveras Enterprise (“Trout population plummets”) and an August 15, 2016 post on the Fishbio blog describe a recent decline in numbers of trout in the lower Stanislaus River. Fishbio pegged the cause of the problem on to four years of drought and to the fact that the Bureau of Reclamation allowed New Melones Reservoir to fall in storage so far as to lose its cold water pool needed for trout production. As reported in the Enterprise, the Oakdale Irrigation District and South San Joaquin Irrigation District issued a statement arguing that “flawed science” in the National Marine Fisheries Service’s 2009 biological opinion issued for the operation of the Central Valley causes federal dam operators to release water in ways that do not benefit steelhead and trout. The Enterprise quotes the Districts as stating: “The current flow standards are destroying the fisheries that they are intending to protect and doing so at the expense of Central Valley agribusiness and urban interests, who also depend upon a healthy and sustainable river.” 

The irrigation districts would prefer that the water released for fish be allocated instead to their constituents. Lost in the discussion is the notion that reducing river flows is not the only way to maintain storage levels in New Melones Reservoir. If the irrigation districts had taken less water over four years of drought, the cold water pool in New Melones could have ended up, in 2015, in much better shape. But the Districts lay the decline of “trout” at the feet of the biological opinion. The fish flow prescriptions biological opinion are not designed for “trout.” They are designed for steelhead migration to the Bay-Delta and ocean. The biological opinion prescribes multi-day spring pulses in flow up to several thousand cubic feet per second to stimulate steelhead (and juvenile salmon) emigration toward the ocean. It states in part:

Objective: To maintain minimum base flows to optimize CV steelhead habitat for all life history stages and to incorporate habitat maintaining geomorphic flows in a flow pattern that will provide migratory cues to smolts and facilitate out-migrant smolt movement on declining limb of pulse. 1

Steelhead need stimulus to migrate. They need the benefits of higher velocities and more turbid water to migrate successfully. Without stimulus, potential steelhead will stay and become resident trout. Mother Nature has given them the inherent knowledge that to go without the flow is to die along the way.

Flow in the Stanislaus River is controlled by operations of New Melones Reservoir (Figure 1). The premise of the article and post is that reservoir drawdown from pulsed flow releases caused the high water temperatures in the lower Stanislaus River that resulted in high trout mortality and the low numbers of trout observed in the snorkel surveys. There is no doubt that low reservoir levels led to warmer water being released into the lower Stanislaus from Goodwin Dam. The information presented in the Fishbio post and report shows clearly that water temperatures were 5 to 10°F higher than normal in the lower Stanislaus, reaching the stressful level of 65°F or even higher downstream of Goodwin Dam at Orange Blossom Bridge (Figure 2). The water temperature criteria prescribed in the biological opinion for the summer at Orange Blossom Bridge is 65°F. The reservoir did fall dangerously low in 2015 (Figure 3).

Figure 1. Map of lower Stanislaus River with USGS gaging stations.

Figure 1. Map of lower Stanislaus River with USGS gaging stations.

Figure 2. Daily average water temperature (°F) in the lower Stanislaus River at Orange Blossom Bridge 2011-2016

Figure 2. Daily average water temperature (°F) in the lower Stanislaus River at Orange Blossom Bridge 2011-2016

Figure 3. New Melones Reservoir storage in acre-feet 2011-2016.

Figure 3. New Melones Reservoir storage in acre-feet 2011-2016.

The Fishbio report relates that water temperature becomes a problem when summer storage falls into the 300-500 thousand ac-ft range.  It would also appear that levels of 500-600 thousand acre-feet, such as those that occurred in summer 2014 and 2016, also lead to elevated water temperatures based on a close look at Figures 2 and 3.

A factor not mentioned by Fishbio is that streamflow in the lower Stanislaus in summer 2015 was lower in 2015, 150-200 cfs, compared to 200 cfs or higher in other summers of the 2011-2016 period (Figure 4).  Such lower flows can also contribute to higher water temperatures.  Lower flows can also affect “trout” survival by significantly reducing rearing space and quality.

A factor that Fishbio did mention was a possible “increase in downstream migration.”  After all, the flow pulses were prescribed to stimulate steelhead smolt emigration.  Flow pulses in combination with higher water temperatures may have stimulated outmigration resulting in lower total numbers.

The main theme of the irrigation districts and Fishbio is that by not providing the pulse flows in spring, it would save up to 100 thousand acre-feet of storage, thus keeping the reservoir higher and water temperatures lower in the river below.  But again, what is missing from the discussion is the effect of reservoir operation on the whole process, and especially on storage.  That effect can be seen in Figures 5a and 5b.  The natural flow regime is highly modified.  The natural winter high flows are retained by the reservoir and released in spring and summer.  Releases to irrigators from storage in 2015 over the April – September irrigation season amounted to approximately four hundred thousand acre-feet (see Figure 3), most of which came from storage carried over from previous years, which made up much of the cold water pool.  This repeated the pattern of previous years, when in fact deliveries to the districts were even higher.  With so little water left in storage by 2015, the districts had no one left to take water from but the fish.

Figure 4. Daily average streamflow (cfs) in the lower Stanislaus River at Orange Blossom Bridge from 2011-2016.

Figure 4. Daily average streamflow (cfs) in the lower Stanislaus River at Orange Blossom Bridge from 2011-2016.

Figure 5. New Melones Reservoir inflow (blue line) and outflow (orange line) in water year 2015 (top) and 2016 (bottom). Note prescribed fall and spring pulse flow releases for salmon and steelhead.

Figure 5. New Melones Reservoir inflow (blue line) and outflow (orange line) in water year 2015 (top) and 2016 (bottom). Note prescribed fall and spring pulse flow releases for salmon and steelhead.

Low Flows – Deadly Water Temperatures

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Low flows in the Sacramento River and Delta lead to deadly water temperatures for Central Valley salmon, steelhead, sturgeon, and smelt, including six state or federally listed endangered species. Water quality standards and operating requirements for the state and federal water projects should include new flow limits to protect fish.

Sacramento River

Salmon, steelhead, and sturgeon are subjected to deadly spring and summer water temperatures when lower Sacramento River flows fall below 5000 cfs as measured at Wilkins Slough (Figure 1). Low flows and high water temperatures lead to poor survival and increased predation, and block migrations of adult salmon.

Delta

Low flows through the lower Sacramento River channel in the Delta also lead to deadly water temperatures for salmon and smelt. When Delta inflow falls below 10,000 cfs, water temperatures become deadly for Delta Smelt (Figure 2) and salmon (Figure 3).

Figure 1. Daily average water temperature and river flow in the Sacramento River at Wilkins Slough (RM 125) 2007-2016. Water temperatures greater than 75°F are lethal to salmon and sturgeon, and block salmon migration. The water quality standard for the lower Sacramento River is a limit of 68°F. Temperatures above 68°F are stressful to salmon, sturgeon, and steelhead, and lead to increased risk of predation, lower survival, and poor reproductive success.

Figure 1. Daily average water temperature and river flow in the Sacramento River at Wilkins Slough (RM 125) 2007-2016. Water temperatures greater than 75°F are lethal to salmon and sturgeon, and block salmon migration. The water quality standard for the lower Sacramento River is a limit of 68°F. Temperatures above 68°F are stressful to salmon, sturgeon, and steelhead, and lead to increased risk of predation, lower survival, and poor reproductive success.

Figure 2. Daily average water temperature and river flow in lower Sacramento River near Freeport. Water temperatures greater than 73°F are lethal to smelt and block salmon migrations.

Figure 2. Daily average water temperature and river flow in lower Sacramento River near Freeport. Water temperatures greater than 73°F are lethal to smelt and block salmon migrations.

Figure 3. Daily average water temperature in the south Delta at Clifton Court 2009-2016. Water temperatures greater than 25°C (77°F) are lethal to salmon and smelt.

Figure 3. Daily average water temperature in the south Delta at Clifton Court 2009-2016. Water temperatures greater than 25°C (77°F) are lethal to salmon and smelt.

Puget Sound Salmon Fishing – Closed Until Further Notice

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For the first time in almost 30 years, there may be no salmon fishing in Puget Sound in 2016.  Several reasons are apparent for this situation.  First, the Coho salmon returns this year are projected to be very poor as a result of unfavorable ocean conditions and the drought in many Washington streams that occurred last year.  The projected returns of adult Coho salmon are very low (particularly for non-hatchery or wild fish that are listed as “threatened” under the Endangered Species Act).  There are also concerns about low returns of wild Chinook salmon.

Seasons in Washington are set on an annual basis by the co-managers of the resource.  These co-managers are the Washington Department of Fisheries (WDFW), which represents the non-Indian sport and commercial fishermen on one side and the Indian tribes in Puget Sound, which represent the interests of about 20 different tribes.  This co-management approach evolved after the Judge Boldt decision in 1974 that established the 50/50 split on harvest between the two entities.  Initially, the court system set regulations, but the co-management approach evolved shortly thereafter to let the resource managers set the seasons rather than the court system.

Under the co-management process, seasons have been negotiated and set in the early spring each year.  The co-managers meet, present their positions based on the information each has (including models of the fish returns), discussions are conducted, and the seasons are mutually agreed upon.  These negotiated regulations are then forwarded to the North Pacific Fisheries Management Council, which then provides final review and approval.  Then the National Oceanic and Atmospheric Administration (NOAA) issues permits for the seasons.

This process has worked in finalizing the seasons, until this year.  When the co-managers first met in late April, the WDFW proposed a restricted season that would allow a “selective fishery” for hatchery Chinook salmon along with possible fishing for hatchery Coho.  (Hatchery fish are marked by the removal of their adipose fin).  The Tribes, however, proposed a total closure for all salmon fishing in Puget Sound to protect wild Coho and all Chinook salmon.

In the first two meetings, the co-managers showed no movement toward an agreement on the Puget Sound situation.  (However, agreement was reached on seasons for the Columbia River and the outer coast of Washington and included severely restricted quotas accompanied with selective fishing for marked fish.)   WDFW walked out of the meetings regarding Puget Sound.   Although the two sides have been in further discussion, as of this date – May 19 – no agreement has been made.

To further complicate the situation, WDFW and the Tribes have decided to submit separate proposals to the NOAA in order to obtain separate permits for their proposed seasons.  (NOAA issues the final permits as part of the Endangered Species Act).  NOAA’s response to this has been “WDFW and the Tribes must come to agreement with NOAA offering assistance to the process, but it will not make a decision on the proposals”.  To process these permit submittals, NOAA has estimated that the Tribal proposal (which does include some limited fishing in some isolated situations) could possibly be processed in time for this co-manager’s reduced seasons to go forward.  However, NOAA has indicated that the WDFW proposal could be lengthy (due to the need for public review and comment) and likely could not be processed this year.

In general, the salmon seasons for both Tribal and non-Tribal fishermen in Puget Sound have been severely reduced over the past several decades as a result of lower returns resulting from habitat losses, dramatic increases in predators (birds, seals, sea lions, etc.), and the 50/50 split with the Indian Tribes.  If no agreement can be reached in the next few weeks, there will be no sport/commercial fishing for Puget Sound salmon in 2016.  This outcome will likely result in major regional economic impacts (a sporting goods store has already closed).  There are about 200,000 salmon anglers that have held licenses in the Puget Sound region.  If the closures continue, these fishermen would have no opportunity to fish for salmon in the Puget Sound basin – only ardent fishermen will likely travel to the coastal ports of Washington or the Columbia River to participate in their sport.

In a related development, the WDFW has closed all fishing (all species) in all Puget Sound streams, rivers, and lakes accessible to Coho or Chinook salmon.  These closures include large lakes such as Lake Washington where there is a popular fishery for bass and other warm water species.  In addition, the summer-run steelhead season, another very popular fishery in many Puget Sound streams, usually opens in early June (which is only a few weeks from this date).  This fishery is also destined to remain closed if no agreement can be reached.

Although NOAA has been the Federal agency that was presumed to issue the final permits for the Tribal and the non-Tribal sport/commercial fisheries, much to the surprise of many fishermen and non-fishermen, the Bureau of Indian Affairs approved a separate permit for a limited Tribal fishery for spring Chinook salmon in the Skagit River (a major tributary of Puget Sound).  The fishery was conducted and resulted in several demonstrations by non-Tribal fishermen, both on the Skagit River and at the state capitol in Olympia.

Most of the Tribes favor some type of agreement.  However, two of the Tribes do not favor any agreement except no fishing.  This has complicated the entire negotiation process because all Tribes in the co-management process must agree to the final regulations before they can be submitted for approval.

As a result of this convoluted process, the likelihood of a salmon fishery in Puget Sound this year is clearly in doubt.  Many of the non-Tribal fishermen believe the current negotiation process needs to be overhauled.

FISHBIO Strikes Again – Predation Is the Problem, Not Water Diversions – Right or Wrong?

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On Wednesday, February 10, 2016, the Water, Power and Oceans Subcommittee held a one-panel oversight hearing on “The Costly Impacts of Predation and Conflicting Federal Statutes on Native and Endangered Fish Species.” FISHBIO President Doug Demko was invited to provide testimony on the issue in reference to California’s Central Valley.

FishBio photo

FishBio photo

FishBio’s testimony begins: “California resource agencies sink tens of millions of dollars every year into a failing effort to protect native and endangered fish species, while also bolstering introduced top-level predators that are decimating the very fish they are required to maintain.”

  1. Failure to protect native and endangered fish species in the Central Valley has far more to do with water management within the federal Central Valley Project and State Water Project and lack of protections from water quality standards and biological opinions, especially during four multi-year droughts beginning in the late-1970’s. Over a billion dollars have been spent by federal and state agencies on fish recovery, with strongly positive results between droughts.
  2. In no way have the recovery efforts bolstered introduced top-level predators such as the striped bass. As noted in the testimony, stocking of striped bass ceased nearly two decades ago. Striped bass production had declined dramatically over the past three decades along with the native fish. Summer water quality standards that once protected striped bass were removed twenty years ago.
  3. The increases in stocking of hatchery salmon smolts to over 30 million annually in the Central Valley have encouraged and sustained the remaining striped bass, which now focus more on young salmon. Adult striped bass now concentrate in spring below all the Central Valley salmon hatcheries and dams. Remnants of the once prolific striped bass population await the fat hatchery smolts in all 300 miles to the Golden Gate. A shift in prey and location of prey has forced more Striped Bass into the rivers and tributaries for prey.
  4. Yearly Hatchery Steelhead Photo

    Photo: yearling hatchery steelhead smolt fed on wild salmon fry in American River. (Photo by author)

    The stocking of millions of large yearling salmon and steelhead smolts also contributes directly to predation on wild salmon and steelhead fry. (see photo at right)

  5. Research has shown that habitat changes have had more to do with increased predator populations like largemouth bass in the Delta. Controlling habitat change is the proven way to limit predators, rather than direct control of predators, which does not work (logistically impossible and very costly and inefficient).

“However, only recently has the existing body of science on predation been recognized among fisheries managers as a major source of juvenile salmon mortality.” This statement is simply not true. Hatchery salmon smolts have been trucked to the Bay for three decades to avoid the hundreds of miles of predator gauntlet. Predation studies at specific locations such as the Red Bluff Diversion Dam have long indicated predation problems. The dam was removed because it was a recognized predator “hot spot”.

There is no doubt that predation by non-native fish like Striped Bass and Largemouth Bass is a major factor in Chinook Salmon and Steelhead mortality in the Central Valley. However singling them out as the primary cause of native fish declines misses the key factor: water management. Salmon, smelt, and bass got along well until the State Water Project came on line in the 1970s and increased Delta exports from 2 million to 6 million acre-feet per year. There is no doubt that droughts and climate change have added to or sped up changes; however the underlying problem remains water diversions.

“It has now become clear that predation may significantly limit the success of salmon recovery efforts (NMFS 2009b; Dauble et al., 2010).” While this statement may be true under existing conditions where salmon production is limited by water management and habitat degradation (with predation exacerbated by these factors), the solution should be a broader range of risk factor management, not just a focus on predation. For example, spring reservoir releases can reduce predation risk by speeding emigration, increasing turbidity, and reducing water temperature.

“The survival estimate of 7% in 2012 was much lower than the 40-60% previously estimated by mark-recapture studies conducted by CDFW.” In drought years like 2012, reservoirs capture and retain nearly all winter-spring flows. No doubt this creates better conditions for Striped Bass (and resident Rainbow Trout and Pikeminnow) predation on young salmon that are programmed to emigrate when Mother Nature provides appropriate freshets. So is the problem predation or lack of natural flows? (This problem could be partly mitigated through a more comprehensive approach in the worst case drought years by capturing young salmon in migrants traps and transporting them to the Bay, thus avoiding the predators in the river (and Delta). In such dry years adult Striped Bass could also be effectively captured in upstream migrant traps and transported to the Bay where other types of prey are far more abundant.)

“[N]o changes in sportfishing regulations, and, to date, no meaningful actions of any kind have been taken to accept or address the problem.” Changing sport fishing regulations would be a drop in the bucket and alienate most sport fishermen. Why doesn’t CDFW take the hundreds of thousands of young striped bass salvaged each summer at the Delta export pumps (and returned to the west Delta) and stock them in a southern California reservoir? Because that would cripple the Bay-Delta striper fishery – an angler’s Catch-22. Why doesn’t CDFW take the catch from hundreds of bass tournaments each year in the Delta somewhere other than nice spots in the Delta? Because that would cripple the world-renowned bass fishery – another Catch-22. FishBio describes the bounty fishery on Columbia River predators that are less desired as gamefish. It is altogether different to put a bounty on Striped Bass and Largemouth Bass.

FishBio noted that harvest restrictions on non-native sport fish have recently been removed on the Columbia River to protect native salmonids. “A similar policy change in California, coupled with focused removal and suppression efforts, could lead to improved survival conditions for native species as has been demonstrated on the Columbia River.” Columbia River salmonid fisheries are far more valuable and popular than bass and walleye fisheries. Furthermore, there is little else managers can do on the Columbia to benefit salmon. Water diversions in the Columbia are far less of a problem, and managers on the Columbia have already severely limited hydropower production to provide spring spills for salmon. These actions have brought record or near record salmon and steelhead runs.

In conclusion, Striped Bass and Largemouth Bass are two of the top sportfish in the Central Valley. Destroying their populations and sport fisheries, and associated socio-economic benefits, without addressing water management, the real culprit, will not solve or defuse the problem.

More on Mark-Selective Steelhead Fisheries

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Don Beyer and many others are concerned with the recent movement to limit hatchery production and mark-selective fisheries of Steelhead in the Puget Sound and Columbia River regions in Washington State. At the center of the debate have been proposals to eliminate hatchery programs on rivers with wild Steelhead.1 Typically, WA Steelhead fisheries focused on winter hatchery fish (adipose fin clipped), with catch-and-release of wild non-clipped fish in winter and spring. In recent years, popular mark-selective and wild catch-and-release fisheries have been shut down on rivers in WA with seemingly healthy populations of wild Steelhead.2 Will NMFS extend these strategies to California?
Steelhead Catch Photo

Recent catch of a hatchery Steelhead in the lower American River in Sacramento. (Photo by T. Cannon)

Marking of Hatchery Fish for Selective Fisheries

by Don Beyer

Salmon and steelhead hatcheries have been in existence for decades along the Pacific coast. The purpose of these hatcheries has been to maintain or improve fisheries for sport, commercial, and tribal interests. They are also a key factor in providing mitigation for habitat losses due to water resource projects such as dams, urbanization, land use alterations, and pollution which have negatively impacted wild fish populations.

Hatchery fish are utilized for food consumption by not only humans, but by marine mammals (e.g., Orcas, seals/sea lions, porpoise/dolphins), birds (bald eagles/ospreys/herons), and other fish (e.g., bull trout), many of which are protected under the Endangered Species Act (ESA), Marine Mammal Act, or other similar Federal acts. The sport fishing industry that has developed over decades around fish resulting from hatchery programs also has a very large economic impact involving millions of dollars.

As a result of the ESA and its efforts to protect non-hatchery raised salmon or steelhead, it was difficult for fishermen to distinguish between hatchery and non-hatchery fish and it appeared that harvest would need to be strictly curtailed or eliminated. To resolve this challenge, hatchery fish were required to be clearly “marked” so that they could be differentiated from non-hatchery fish. The most widely adopted approach has been to remove the adipose fin (a small non-functional fin near the tail of the fish) in juvenile fish before they leave the hatchery to migrate to the ocean. In this manner, if a fisherman caught a salmon or steelhead with an intact adipose fin, they were required to carefully release the fish (even if the season was open for that species). This approach (termed “selective fishery”) was to allow fishermen to continue fishing while protecting ESA-listed salmon or steelhead. Without this approach, the sport, commercial, and likely tribal fisheries would have ceased to exist. It took many years in all Pacific coast states, along with the efforts of many people, to get the selective fishery approved and implemented.

Other approaches are also being undertaken to minimize or eliminate interactions of ESA and non-ESA listed fish. For example, in the past, steelhead from Washington state hatcheries were released at the hatchery and often at other locations either upstream, downstream, or even other river systems. To minimize potential interactions with ESA-listed steelhead, this practice has been minimized to releases only at the hatchery. This takes advantage of the exceptional homing abilities of adult hatchery fish to return to their place of origin (i.e., the hatchery), thus reducing the interactions with non-hatchery fish.

Without the adipose-marking of fish, current fisheries would not be able to continue because fish protected under ESA could not be differentiated from hatchery fish. As such, a major food source for humans and other ecosystem components (e.g., those mentioned above) would cease to exist along with the loss of a major industry dependent on hatchery production. Without selective fishing, the only possibility for a return to a harvestable level of fish would be for ESA-listed species to recover to a level of sustainability that includes harvest. This is a long-term undertaking and may not be possible in some areas where the habitat would not sustain recovery. However, in some situations such as the Columbia River system, progress is being made through recovery of habitat, improvements in hydroelectric and hatchery programs, and harvest restrictions. On the latter, the selective fishery approach has allowed a very viable sport, commercial, and tribal harvest to continue.