Scott River Coho Salmon Run – Status Fall 2019

The Scott River Coho salmon population is one of the last remaining self-sustaining wild Coho salmon runs in California and in the Southern Oregon Northern California Coho (SONCC) Evolutionarily Significant Unit (ESU).  The SONCC ESU is listed as “threatened” under the federal and California endangered species acts.  The ESU includes the Rogue River in Oregon and the Klamath River in California.

The Scott Coho run is the major wild Coho population in the Klamath River system.  Scott Coho spawn and rear in Scott Valley, once called “Beaver Valley,” located near Fort Jones.  The run has numbered over 1,000 adult Coho spawners as recently as 2013, but numbered less than 100 as recently as the 2008-09 drought years (Figure 1).

Scott Coho include three distinct sub-populations that have developed because the vast majority of spawners are three years old.  One subgroup, the 2007-2010-2013 sub-group, dominated the population in the recent past, but declined sharply in 2016.  The other two sub-groups have increased slightly since 2008 and 2009 lows.

The spawner-recruit relationship (Figure 2) shows a generally positive relationship between the number of spawners and recruits three years later for each sub-group and the overall population with one distinct outlier (the sharply lower 2016 run).  So why was the 2013 run so high and the brood-year 2013 run in 2016 so poor?

1.      2013’s Good Run

The 2013 run (brood year 2010) got off to a great start in wet water year 2011.  Flows for the fall 2010 spawning run were good from November through January [Figure 3), which ensured spawner access and good spawning conditions throughout Scott Valley.  Flows were also good through the spring and fall of 2011 (Figure 4), ensuring good smolt production and a subsequent strong run in 2013.

2.      2016’s Poor Run

The strong run in 2013 spawned in brood year 2013, which got off to a rocky start in dry water year 2013-14.  Flows in fall-winter 2013-14 encountered by the strong 2013 run were very low through the early winter spawning season (Figure 5), leading to an unusually protracted run of adult spawners (Figure 6) and poor accessibility to good spawning areas.  Spawning habitat quality and quantity likely also suffered from low flows.  Flows were then very low from spring through fall of 2014 (Figure 7), likely resulting in poor over-summer survival and low smolt production for brood year 2013.

In conclusion, the Scott Coho salmon population continues to suffer from low seasonal streamflow, especially in drought years like water year 2013-14.  The population would benefit from improved summer-through-fall streamflows.  It will also benefit from the watershed habitat restoration actions being implemented by landowners, CalTrout,  the Scott River Watershed Council, Siskiyou RCD, Scott River Water Trust, California Department of Fish and Wildlife, Quartz Valley Indian Reservation, and other stakeholders.

Figure 1. Escapement of adult Coho salmon to the Scott River from 2007 to 2019. Data source: CDFW, Yreka, CA.

Figure 1. Escapement of adult Coho salmon to the Scott River from 2007 to 2019. Data source: CDFW, Yreka, CA.

Figure 2. Spawner-recruit relationship for Scott River Coho salmon. The number represents recruits (spawner counts) for that year versus spawners counts from three years earlier. For example: “13” represents spawner counts (recruits) in fall 2013 versus spawner numbers three years earlier in 2010. Number color represents different spawner subgroups (blue=subgroup 10-13-16-19). The Red circle highlights significant outlier in 2016. The Yellow line is trend-line for years other than 2016.

Figure 3. USGS gaged daily average flow (log scale) in lower Scott River, Klamath River tributary, 9/1/2010-2/1/2011, with 78 year average daily median flow for that date.

Figure 4. USGS gaged daily average flow (log scale) in lower Scott River, Klamath River tributary, 4/1/2011-11/1/2011, with 78 year average daily median flow for that date.

Figure 5. USGS gaged daily average flow (log scale) in lower Scott River, Klamath River tributary, 9/1/2013-2/1/2014, with 78 year average daily median flow for that date.

Figure 5. USGS gaged daily average flow (log scale) in lower Scott River, Klamath River tributary, 9/1/2013-2/1/2014, with 78 year average daily median flow for that date.

Figure 6. Scott River adult salmon collection weir counts of Coho salmon for fall-winter 2013-14. Data source: CDFW Yreka, CA.

Figure 7. USGS gaged daily average flow (log scale) in lower Scott River, Klamath River tributary, 4/1/2014-10/31/2014, with 78 year average daily median flow for that date.



Klamath’s Shasta and Scott Rivers – Update Fall 2019

In two May 2017 posts1, I discussed the status of fall-run Chinook salmon in the Scott River and Shasta River through the 2016 runs. This post updates the escapement record for the two rivers through the 2018 runs with preliminary data on the 2019 runs.

Scott River

After a slight uptick in the run in 2017, the Scott fall-run 2018 escapement fell below the 2015-2017 runs (Figure 1); all were affected by the 2012-2016 drought. The run total as of mid-October 2019 was 23. It is too early for a coho update, but the run continues at minimum levels2 with a disappointing strong-brood-year 2016 performance3. A poor 2016 run is likely to lead to a poor 2019 run.

Shasta River

In sharp contrast to the Scott, the Shasta River run continues to improve over its historical record (Figure 2). The run total as of mid-October 2019 was 2,722. The Shasta River coho population remains at critically low levels.

The remarkable recent success of the Shasta River Chinook run from habitat restoration and improvements in water management (and the lack thereof on the Scott River) continues to be undermined by misinformation promoted within the agricultural community. A February 2019 article in the news outlet Grist reported:

In 2016, The Nature Conservancy announced plans to sell Shasta Big Springs Ranch. But without its water, which California Fish and Wildlife still owns, the land isn’t of much use for agriculture. And the fish don’t seem to be doing much better, either — though salmon still spawn at Big Springs, their numbers continue to fluctuate wildly from year to year. It seems that in this ecosystem so changed by people, the salmon need some local stewardship to thrive…

The Scott River remains “the most productive coho stream in California,” according to the nonprofit California Trout. When I spoke to Plank last he told me that the river was splashing. “These fish hatched on this ranch during the last drought,” Plank said. “Today, they’re returning.” [emphasis added]

The article asks the rhetorical question: “So how did such similar conservation efforts go so right at Scott River Ranch and so wrong at Shasta Big Springs Ranch?” For fall-run Chinook, at least, the numbers tell a different story. As for coho, there is no evidence that the population is going anywhere but downhill.

The difference in water management between the two rivers is readily seen in the flow records over the last four years (Figures 3 and 4). The Shasta River has improved flows, whereas the Scott River has had historically low fall flows that keep salmon from ascending from the Klamath to the Scott River spawning grounds. Low summer and fall flows (Figure 3) have also led to very poor survival of young coho and Chinook salmon over-summering in the Scott River.

Figure 1. Escapement of adult fall-run Chinook salmon to the Scott River from 1978 to 2018. Data source: CDFW.

Figure 2. Escapement of adult fall-run Chinook salmon to the Shasta River from 1978 to 2018. Data source: CDFW.

Figure 3. Scott River streamflow 2016-2019. Source:

Figure 4. Shasta River streamflow 2016-2019. Source:



Saving Killer Whales By Increasing Salmon Production

In a January 18, 2019 post, I related the state of Washington’s plan to increase the state’s hatchery salmon production to recover salmon populations and help the endangered southern population of killer whales.  In response to an executive order by the governor of Washington, the Washington Department of Fish and Wildlife’s proposed broad measures to increase the numbers of hatchery-raised salmon smolts released into killer whale migration areas that have minimal numbers of wild salmon.  The program would also enhance commercial and sport fisheries for salmon.  Much of the hatchery program would remain committed to recovery of threatened and endangered wild salmon stocks, which would also get a boost in essential habitat restoration.

The proposal in Washington state calls for an additional 30 million smolts for the Puget Sound estuaries (near Seattle) and an additional 20 million for the Columbia River estuaries, 50 and 20 percent increases, respectively.  The proposal recognizes:

 [H]atchery practices can pose serious genetic and ecological risks to wild populations if not managed carefully with full consideration of all that has been learned over the history of salmonid hatchery programs in the Pacific Northwest. However, the design of this proposal strives to minimize such negative impacts and to afford protection to the existing wild chinook populations to the greatest extent possible.

Elements of the program would include releasing hatchery smolts in lower river and estuary areas.  The program is designed to minimize effects on wild salmon by keeping these releases outside of the normal rearing and migration routes of wild salmon.  In some cases, hatchery salmon fry would be transported to net pens in lower rivers and estuaries for rearing and eventual release of smolts near the ocean, thereby further increasing smolt survival.  Returning adult salmon would home in on such sites, creating opportunities for terminal fisheries for hatchery salmon while retaining upriver spawning grounds for wild salmon.

A similar program is being planned and tested in California in the San Francisco Bay Estuary of the Sacramento and San Joaquin rivers.  Central Valley hatchery salmon smolts are already being trucked to the Bay and nearby coastal estuaries.  A new program element under consideration is the trucking of fry to local Bay estuary net pens for rearing.  If successful, this would create new terminal sport and commercial fisheries, while enhancing coastal fisheries and prey for the California Killer Whale populations.

One goal of the program in California would also be to shift hatchery salmon fisheries away from rearing areas and migration routes of wild salmon.  Rearing fry and releasing smolts in areas not frequented by wild salmon should reduce the effects of the hatchery program on wild salmon.  Similarly, terminal fisheries would focus harvest away from migration routes of wild salmon and reduce competition with wild salmon in spawning areas in upper rivers.  Commercial and sport fisheries would be enhanced along the coast.  New terminal fisheries would be created at estuary and coastal release sites that attract adults originally released at the sites as smolts.

If all goes well, such programs will benefit killer whales, sport and commercial fisheries, and wild salmon population (through reduced competition and better harvest management).

For more detail on Oregon and Washington Select Area Fisheries Enhancement programs see




Selective Chinook Salmon Sport Fisheries in Puget Sound With notes on variants for Coho salmon and Steelhead.


The Endangered Species Act (ESA) imposed complex challenges to the management of the sport fishery for Chinook salmon in Puget Sound, Washington State. In order to protect limited stocks of “native or wild” Chinook (i.e., those that are not from hatchery origin and naturally spawn in streams), total closures to sport fishing were strongly considered.

Wild and “hatchery” Chinook (i.e., those that are reared in a hatchery) co-mingle in the same Puget Sound habitat. The hatchery fish are often sufficiently abundant in many areas to allow some level of sport fishing. Total closure of the sport fishery for all Chinook was therefore a major issue for sport fishermen because of the high economic value of the sport, the potential overabundance of adult hatchery fish, and the sport of catching this prized species.

To differentiate hatchery from wild salmon, the adipose fin is removed from hatchery-reared smolts before release. Thus, when an angler brings a Chinook to shore or a boat, the angler can visually determine if it is from hatchery origin, based on the absence of this fin. This allows a mark-selective fishery targeting hatchery fish.

Mark-selective Chinook salmon fisheries are sometimes further constrained by “encounter” quotas. In Puget Sound, quotas for angler “encounters” (a combination of legal-size Chinook, wild Chinook, sublegal hatchery fish, and sublegal wild fish) are established annually for 9 specific marine management areas. For selective river fisheries in the Puget Sound area, the encounter approach is not used.

Current management using quotas on catch and encounters allows sport fisheries on hatchery Chinook salmon. Co-managers Washington Department of Fisheries (WDFW) and Native American Tribes use three major methods to manage the Chinook sport fisheries in Puget Sound:

  1. review of angler punch card data,
  2. creel census surveys supplemented with test boat fishing and aerial surveys, and
  3. quotas on encounters in areas of Puget Sound where sublegal and legal sized Chinook salmon co-mingle.

Punch Cards

In addition to a fishing license, anglers fishing for salmon (all species) and certain other species (e.g., steelhead and halibut) must also purchase a punch card. When one of these species is caught and kept, the angler records the date, location, species, and other information on the card. The punch card must be returned to the WDFW at the end of the recording season. If the cards are not returned, there is a penalty charge made on the next license purchased. The card is used to determine annual harvest and historical trends for the various management areas.

Creel Census

To supplement the punch card information, additional “real time” data are monitored through angler “creel” surveys at various sites. These face-to-face surveys collect information on species caught and kept, number of fish released (including any wild salmon, sublegal fish, others species), hours and management area fished.


Recording encounters involves the reporting during creel surveys of all Chinook kept and released, including whether fish caught were legal-sized and adipose clipped, legal-adipose intact, sublegal-adipose clipped, or sublegal-adipose intact. Information collected during the creel surveys also records Chinook retained and an estimate from the angler of those that have been hooked and released (legal, sublegal, or native). This information is supplemented by test boat fishing and aerial surveys.

During the pre-season, each of the 9 management areas in Puget Sound is assigned specific seasonal encounter quota numbers. If any of the quotas are reached in an area, that area is closed to further fishing for Chinook.


Mark-selective sport fisheries on hatchery salmon in the Puget Sound have been allowed through the use of quotas on angler catch and encounters for specific management areas. The quotas are determined during the pre-season by the fisheries co-managers WDFW and the Tribes. Quotas are derived from a model that includes historical punch card data, spawning surveys from earlier years, and other population and catch data.

The sport fishery for Chinook has severely declined in recent decades. There is a wide array of potential reasons for this decline. These include massive increases in predators (e.g., seals and sea lions), ocean conditions, loss of freshwater habitat, and others. In past decades, fishing for Chinook salmon was open the entire year, with much higher daily limits (up to 3 fish). The fishery has been severely reduced to only a few weeks in summer and limited months in the winter, often with only a 1 fish daily limit. The addition of the encounters approach in recent years has also contributed to large crowds that are condensed into the shortened periods. This, for some, has catching a prized Chinook salmon a lot less enjoyable.

In general, the encounters approach has been useful for allowing Chinook salmon sport fishing to continue on a limited basis while maintaining protections for wild Chinook. There are some drawbacks, however. For example, if the pre-season estimate of Chinook abundance for a particular management area is underestimated, the encounters quota may be reached early and the season closed, even though there may be substantially high survival rates that might have allowed a higher quota value.

Coho salmon and steelhead are also adipose clipped at the hatchery. This allows selective sport fisheries for these species to continue as well, while allowing release of wild spawning adults. However, the encounters methodology is not currently used for these species (capture of sublegal fish is low). In areas where adult Coho populations are low, a selective fishery may occur, in which only hatchery fish are allowed to be retained. However, in areas where populations of “native” Coho are abundant, both wild and hatchery Coho may be kept.

In general, nearly all steelhead management areas in Washington require release of native steelhead, which, in most cases, have a high survival rate when released.

In sum, these mark-selective sport fisheries in Puget Sound allow sport fisheries that otherwise might be banned altogether. Harvest of hatchery fish may also help reduce competition with wild fish for spawning habitat and food resources.


No Funding Help for Central Valley Salmon Hatcheries: Sacramento Valley Salmon Recovery Program and Proposition 3 Strike Out

California’s salmon hatchery programs badly need major projects and upgrades.  The future of wild and hatchery salmon runs, as well as commercial and sport fisheries in California, depends on these programs.  However, hatchery programs are operated and funded under antiquated water project mitigation programs that lack a progressive approach (and funding) for hatcheries in salmon ecosystems in California.  And neither the Sacramento Valley Salmon Recovery Program (SVSRP) nor Proposition 3 includes investments in hatcheries.

California Salmon Hatcheries:

  • Iron Gate Hatchery: Coho, Fall Chinook and Steelhead (Klamath River)
  • Trinity River Hatchery: Coho, Fall Chinook, Spring Chinook and Steelhead (Trinity River)
  • Nimbus Hatchery: Fall Chinook and Steelhead (American River)
  • Mokelumne Hatchery: Fall Chinook and Steelhead (Mokelumne River)
  • Merced Hatchery: Fall Chinook (Merced River)
  • Feather River Hatchery: Fall Chinook, Spring Chinook and Steelhead (Feather River)
  • Coleman National Fish Hatchery: Fall Chinook, Late-fall Chinook and Steelhead (Battle Creek)
  • Livingston Stone National Fish Hatchery: Winter Chinook (Sacramento River)

The California Hatchery Review Project and Hatchery Science Review Group (HSRG)1 identified major problems/issues, goals, and expectations related to California salmon hatcheries:

  • Serious loss and degradation of habitat limits natural production of salmon and steelhead in California.
  • Hatchery program goals have been consistently expressed in terms of juvenile production rather than adult production.
  • Program purposes have not been clearly defined.
  • Hatchery monitoring and evaluation programs and Hatchery Coordination Teams are needed.
  • Program size has been set independent of any consideration of potential impacts of hatchery fish on affected natural populations.
  • Off-site releases promote unacceptable levels of straying among populations.
  • Marking/tagging programs are needed for real-time identification of all hatchery-origin Chinook salmon returning to hatchery facilities.
  • Standards for fish culture, fish health management and associated reporting are inadequate and need to be improved.
  • Populations and population boundaries have not been established for non-listed species and are needed for effective development of integrated hatchery programs.
  • Harvest management of Sacramento River Fall Chinook should account for the productivity of naturally-spawning adults.

Program goals:

  • Improving the efficiency of hatchery operations
  • Reducing the impact of hatcheries on natural populations
  • Supporting commercial, tribal, and recreational fisheries

Expectations from hatchery programs:

  • Reduction in the domestication of hatchery fish
  • Reduction in the negative impacts of hatchery fish on natural spawning populations
  • Improved prospects for the long-term successful coexistence of hatchery and natural fish

NMFS’s Salmon Recovery Plan, in addition to supporting the recommendations of the HSRG, also promotes the following action:  “Develop and implement an ecosystem based management approach that integrates harvest, hatchery, habitat, and water management, in consideration of ocean conditions and climate change (Lindley et al. 2009).”

Because scientific studies have shown that hatcheries reduce the long-term fitness and survival of salmon species, and California’s listed salmon and steelhead cannot be sustained without hatcheries, it is imperative that hatchery programs be upgraded to safeguard the future of salmon in California.  One way to accomplish this goal and the others described above is to adopt the goals and objectives of a Conservation Hatchery Strategy.

First, there needs to be a shift away from hatcheries as mitigation for long-ago-built dams and water diversions, and a shift toward hatcheries contributing directly to salmon recovery and conservation.  Dumping tens of million salmon and steelhead hatchery smolts at the eight hatcheries or trucking some to the Bay may sustain a minimal coastal fishery, but it will not bring recovery or delisting of endangered populations.  Conservation hatcheries are a necessary tool for salmon recovery.

The eight hatchery programs need funding to convert them to conservation hatcheries.  That funding could come from the SVSRP and resource agency programs, and future ballot initiatives, as well as mitigation programs.  At a minimum, the SVSRP should be integrated into an ecosystem-based management approach that includes conservation hatcheries.