Recovery Project Fall Chinook Salmon 2014-2015 Citizen Monitoring

Prepared By: Patrick Higgins, ERRP Volunteer Coordinator

With Funding From: Patagonia World Trout Initiative Salmon Restoration Association & Humboldt & Mendocino Redwood Companies

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 i Acknowledgements

The Eel River Recovery Project (ERRP) was able to again estimate the size of the 2014-2015 Eel River fall Chinook salmon run, although flows made planning dives and tracking late run fish a challenge. Similar to the prior two years, we enjoyed substantial support from the co-sponsoring Wiyot Tribe and the Humboldt Redwood Company (HRC). Primary funding that made this project possible came from the Patagonia World Trout Initiative and the Salmon Restoration Association, which sponsors the World’s Largest Salmon BBQ in Fort Bragg. Additional funding from HRC and the Mendocino Redwood Company was also much appreciated.

Dozens of people volunteered to dive the lower Eel River in 2014 and we really appreciate the commitment and enthusiasm of participants. We thank the well-trained student recruits from the Humboldt State University scientific dive class for joining us for the successful October 11 dive. ERRP is also grateful to HRC staff for organizing and participating in the main Eel River Dyerville to Holmes dives on November 19 that provided valuable data. We also extend thanks to dozens more of the volunteers who surveyed many river reaches and tributaries and reported on migration and spawning activity. They were able to help us discern the pattern of distribution and abundance, despite restricted windows of visibility caused by rains that elevated turbidity.

Fisheries biologist Scott Harris of the Department of Fish and Wildlife (CDFW) once again provided data on fall Chinook salmon from the Van Arsdale Fish Station. ERRP thanks Park Steiner, Steiner Environmental Consulting, and the Pacific Gas and Electric Company (PG&E) for sharing upper Eel River Chinook spawning data. We are also thankful for media coverage that helps us recruit volunteers, including KMUD radio, KAEF TV, Redwood Times, Independent, Trader, Observer, and the Willits News.

Special thanks this year go to Eric Stockwell, who is the ERRP Outdoor Coordinator and operates Loleta Eric’s Guide Service. He watched the river daily during the period of early Chinook salmon entry, measured pool depths before dives, never missed a dive survey, and did spawner surveys through early January. Diane Higgins also deserves special appreciation for updating the ERRP website, posting reports and You Tube videos, and for utilizing her editing skills to greatly improve this document.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 ii

ERRP Thanks Volunteers & the Community for Support

Donate on-line to support the 2015-2016 Survey: www.eelriverrecovery.org/donate

Eric Stockwell Diane Higgins David Sopjes Dave Wagner Sal Steinberg Dorje Bond Paul Trichilo Stephen Davies Paul and Barbara Domanchuk Ernie Merrifield Walker Wise Veda Hoyes Hiromi Uno Steve Rosenberg Tam & Malanian Adams Conrad Calimpong Emandal Amy Conrad Greg Byers John Casali Graham and Dotti Russell Cole Glover Karen & Scott Walsh Bruce Hilbach-Barger Sharon & Dean Edell Dennis Halligan Seth Rick Bob Lashinski Erick & Sunshine Johnston Doug Manning David Weitzman Bob Vasser John Evans/Big Bend Lodge Zack Cinek Katrina Nystrom Cathy Warren Jeff Hedin Scott Harris Jim Williams Park Steiner Stephen Kullman Laura McBride Tim Nelson Jake Malone Vincent DiMarzo Jeff Wells Julie Donnell Sage Halvorson Angela Moran Willie Grover Andrew Pellkofer Aaron Griffith Angela Moran Ryan Damron/Gomde Monastery Allysa Marquez Mickey Bailey Jake Malone Billy Evans/ Eureka Ready Mix Jeremiah Ets-Hokins Laura McBride Taylor Strawn Matt Hanington Brian Andros Alex Gless Todd Kramer/Pacific Watershed Assoc. Mike Vitiello Louisa Bolton-Ast Sonny Elliot/Cahto Tribe Laytonville

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 iii Table of Contents

Acknowledgements ...... ii Executive Summary ...... 1 Time, Location and Conditions of Surveys ...... 2 Methods...... 5 Results ...... 7 Discussion ...... 13 Conclusion ...... 19 References ...... 20

Attachment A. Lower Eel River Fall 2014 Chinook Dive Census Methods and Habitat Assessment

Attachment B. Volunteer Chinook Salmon 2014-2015 Migration and Spawning Observation Database

Attachment C. ERRP 2014-2015 Chinook Salmon Reports and Video Documentation

Attachment D. Steiner Associates Consulting Database of Upper Eel River 2014-2015 Chinook Salmon Spawning, including Tomki Creek

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 iv Executive Summary

The Eel River Recovery Project 2014-2015 Citizen Assisted Chinook Salmon Monitoring project faced the most challenging survey conditions in three years of effort. As the survey began in late August, the Eel River was disconnected and impassable because of historic low flows. Early- season rain events in late September and October provided sufficient flow for Chinook salmon to migrate out of the estuary and well upstream, but also caused turbid conditions and flows that prevented several scheduled dives. The October 11, 2014 dive count was 2,467 Chinook salmon - the highest ever for a similar early-October time period. The first pulse of Chinook salmon moved upstream around Halloween. The second wave of fish that followed was decidedly smaller than in 2012. Probably not more than 5,000 fish were holding in the entire lower Eel during the period of November 12-19.

At the Van Arsdale Fish Station (VAFS) CDFW counted only 584 Chinook salmon and 219 steelhead. These comparatively low returns may have been influenced by the timing of flow in 2014-2015. We observed large schools of Chinook salmon downstream and many spawned in the main Eel River before higher flows allowed them to reach the (VAFS). Fish spawning below VAFS may actually have a better chance for survival because the reach between the Scott and Cape Horn dams lacks spawning gravel and good Chinook fry rearing habitat.

This year’s distribution of Eel River Chinook spawning was the inverse of 2013-2014, when most fish spawned in lower mainstem reaches due to lack of winter rain. This year (2014-2015), no fish stopped to spawn in lower river locations. Instead, most spawned in the upper-most accessible reaches, including the headwaters of above Willits, in Ten Mile Creek above Laytonville, in the upper Middle Fork Eel and Black Butte rivers, the South Fork Eel near Branscomb, and in the above Bridgeville. While well distributed, the numbers of migrating and spawning Chinook were modest compared to previous years, such as 2010 and 2012.

Late season surveys of Bull Creek, Sprowel Creek and upper tributaries found signs of spawning around Christmas and New Years, but no spawning was noted in Bear, Chadd, or Salmon creeks, which all show signs of sediment impairment. Steiner Environmental Consulting (SEC) surveys in the upper Eel River basin found only 108 live fish or carcasses in Tomki Creek, and just 12 redds. This low return is typical of recent years and indicative of the stream’s compromised ecological condition.

We estimate the proportion of two year old male Chinook (jack salmon) as 26%, which is a sign of high survival of the 2013-2014 brood-year. We observed several sturgeon in the lower Eel River, with groups seen in the estuary in October and more seen up river during the dives. Although most were green sturgeon, the presence of white sturgeon was also confirmed.

Our estimate for the 2014-2015 Eel River fall Chinook salmon run is 12,500-20,000 fish, compared to 20,000-50,000 in 2012-2013, and 14,900-25,000 Chinook in 2013-2014. It is very encouraging and somewhat surprising that the population continues to exceed 10,000 fish despite the continuing drought. This population range is similar to that measured during the late 1950s (USFWS 1960) and indicates that the short term risk of extinction for Eel River Chinook salmon is low.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 1 Time, Location and Conditions of Surveys

Due to the prolonged drought, the flows of the lower Eel River were very low (Figure 1) The river actually dried up in one reach near Fortuna (Figure 2) just as the fall Chinook salmon run was about to start. The U.S. Geologic Survey (USGS) gauge on the Eel River at Scotia recorded 28 cubic feet per second (cfs) (Figure 3), the lowest flows for the date since 1924. We conducted a survey on August 26 to photo document conditions, which were approaching stagnation. ERRP volunteers watched the lower Eel River closely because of the potential for a fish kill.

On September 10, riffles were too shallow for Chinook salmon to pass upstream of the Drake Pool, and fish attempting to travel above Fernbridge ran the risk of getting stranded. Despite the Eel River being dry between pools, there were adult summer steelhead and numerous half pounder steelhead in the Boxcar Pool and in the 12th Street Pool. An adult sturgeon was sited in the 12th Street Pool. Increased flow releases from the Potter Valley Project in late August and a light rain event on September 17, caused the river to rise slightly, but passage for Chinook salmon was still not possible at Fernbridge. As of September 20, no fish were moving up from the estuary. Heavier rain on September 24 pushed the lower Eel River over 200 cfs for a few hours, and allowed the first large group of Chinook salmon to move upstream and stage in Fortuna pools.

Flows at Scotia subsided to 71 cfs by October 11, water clarity improved, and conditions for dive observation were very good. Only the 12th Street, Boxcar, and Drake pools (Figure 4) were surveyed because the other pools that were monitored in prior years were too shallow to hold adult Chinook in fall 2014. September 24 flows had been insufficient to wash away algae, and divers who encountered it in the Boxcar Pool contracted swimmer’s itch. The continuous recording temperature probe in the main Eel above Howe Creek registered a maximum of 72.6 F (22.6 C) on October 11, which would be stressful for adult Chinook salmon. However, water temperatures in Fortuna pools on the day of the dive were a maximum of 67 F (19.4 C), which is not stressful.

ERRP reconnaissance on September 24 found that no Chinook salmon had been able to move upstream above the 12th Street Pool. Consequently, the scheduled October 10 dive of the Weymouth Bluffs Pool and the Eel River-Van Duzen River convergence pool was cancelled. The HRC-led survey above Scotia, planned for October 9, was also cancelled. Two subsequent dive series scheduled for October 24-27 and November 7-10 were not conducted because flows rose, clarity dropped, and/or angling re-opened, posing the risk of conflicts. Water clarity upstream in the main Eel River at Dos Rios and Alderpoint and in the South Fork at Garberville from November 9- 11 was 25-30 feet and afforded very good conditions for underwater video.

The lower river also dropped and cleared enough by November 12 to allow a small group of ERRP volunteers to dive the 12th Street Pool on and confirm the presence of Chinook salmon. Water clarity remained good until HRC and ERRP performed the last organized dive on November 19. Eel River flows throughout the 2014-2015 season were well timed and sufficient to insure adult Chinook salmon passage throughout the watershed (Figure 5). At Scotia in December 2014, flows peaked at 128,000 cfs, and in February 2015 flows were and 148,000 cfs. March 2015 was dry, however, and the visibility cleared as newly emerging Chinook fry were migrating downstream.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 2

Figure 1. Eel River looking upstream from Fernbridge just above tidewater, with the riffle too shallow to cross for migrating Chinook salmon. USGS Scotia was 28 cfs. Photo from ERRP. 8/26/14.

Figure 2. Eel River below River Lodge and the 12th Street Pool without surface flow connection. Photo by David Sopjes. 8/29/14.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 3

Figure 3. Lower Eel River flow from June 15 to September 30, 2014 at Scotia USGS gauge.

Figure 4. Lower Eel pools suitable for holding Chinook salmon in 2014 that were surveyed on October 11.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 4

Figure 5. The logarithm of average daily flow at six Eel River USGS flow gauges provides a visual summary of low flow and peak flow patterns throughout the 2014-2015 fall Chinook migration, spawning and egg incubation period.

Methods

The 2014-2015 run size estimate relies on organized volunteer dive counts, solo and small team dive observations, volunteer accounts of migration and spawning, VAFS returns, and spawner surveys by SEC and ERRP. In 2013-2014, low flows allowed extensive spawner surveys using kayaks, but no such surveys were possible in 2014-2015.

Pool Habitat Mapping: In late September, prior to dives, ERRP volunteer Eric Stockwell measured pool depths in the lower Eel River using a sonar device operated from a kayak. These values were then transcribed onto aerial photos for use by dive teams.

Dive Methods: Dive methods were similar to previous years and those used elsewhere in California (Garman 2012) and are described in detail in the 2014 ERRP dive methods memo (Attachment A). Timing of 2014 dives was coordinated with Wiyot Tribe Environmental Department staff, HRC, and ERRP. Jack salmon were defined as Chinook salmon shorter than 24” in length, and half-pounders were steelhead less than 20” in length. Teams of 11 and 8 were used for dive observations on October 11, and November 19, respectively (Figure 6).

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 5

Figure 6. HRC and ERRP dive team assembled at Dyerville and ready to get in the water on November 19, 2014. Photo by Nick Prete.

Dennis Halligan, of Stillwater Sciences, shared observations from his lower Eel River November 10 survey, which follow methods similar to those he has used since 1995 (Halligan 1998).

ERRP took underwater video of concentrations of fish in clear water during solo dives on November 9-11 in the main Eel at Alderpoint and Dos Rios. A team of six ERRP volunteers in the 12th Street Pool on November 12 was not sufficient to get a complete count of Chinook salmon, but useful data were obtained. No scuba gear was employed in 2014-2015 fall Chinook dives.

Volunteer Observations: Forty-two volunteers provided 70 phone or email messages chronicling the migration and spawning activity. The names of these volunteers are omitted from the narrative but are available in Attachment B. In one case, a volunteer provided a photograph taken at Dos Rios on November 5, 2014 that was of sufficient clarity to count hundreds of individual fish. Other volunteers provided video documentation of migration and spawning activity at various locations.

Tributary Surveys: Surveys (Table 1) to gauge Chinook salmon spawning and habitat conditions in tributaries were conducted on foot, wading or walking the stream bank for reaches of up to a mile in length. In addition to counting live fish, carcasses, and redds, we noted and photographed habitat conditions such as pool depth, stream substrate size, suitability for spawning, and signs of sediment deposition or bed scour, which are reported separately (Attachment C). Steiner Environmental Consulting (SEC) performed weekly Chinook salmon spawning surveys below the Potter Valley Project (PVP) and in Tomki Creek from mid-November 2014 to early January 2015. These followed the methods used for 30 years of monitoring on behalf of PG&E. (Attachment D).

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 6 Table 1. Dates of ERRP tributary spawner surveys. Date Streams December 24, 2014 Bull Creek December 31, 2014 Bear (Shively), Chadd and Sprowel Creeks February 14, 2015 McCoy, Red Mountain, Cedar, Ten Mile & Streeter Creeks February 15, 2015 Redwood (Branscomb) & Jack of Hearts, Creeks

Results

The ERRP 2014-2015 fall Chinook monitoring population estimate is formulated using dive counts, volunteer observations, tributary surveys, and the VAFS Chinook salmon counts.

Pool Habitat Mapping: In late September, prior to dives, ERRP volunteer Eric Stockwell measured pool depths in the lower Eel River (Table 2), which were used to create dive maps (Figure 7). These data helped us understand pool habitat quality and holding capacity, as well as where fish might be located. Only four pools were capable of holding Chinook salmon, and the Weymouth Bluff Pool above the Van Duzen River was not accessible to early run fish.

Dive Counts: During the ERRP October 11 dive, we counted a total of 2,467 Chinook salmon, comprised of 556 jacks and 1,911 adults. We also counted 62 adult steelhead, and 95 steelhead half pounders (Table 3) and (Figure 8). Two adult green sturgeon were also counted. This is the highest number of Chinook seen during an early October dive survey since 2010 (Figure 9). The HRC dive on November 19 found 770 adult Chinook and 290 jacks in four pools from Dyerville to Holmes. Most Chinook salmon were in the Dyerville pools above and below the convergence of the South Fork Eel River. None were seen in the lower High Rock Pool and 75 adults and 5 jacks were counted in the Holmes Bluff Pool. Four adult steelhead and several hundred suckers were observed in the lower Dyerville Pool and there was an adult sturgeon in the Holmes Pool.

Table 2. Pool depths in lower Eel River ascertained using sonar. Pool Name Maximum Depth Note Fernbridge 10 ft. No current near scoured area. Worswick 6.5 ft Mostly less than 4 ft. deep. Too shallow for salmon. Drake 9.5 ft. Deep at rip rap, but mostly 3-4 feet deep. Boxcar 7 ft. Pocket at front 6.5 ft. Depth increased downstream. 12th Street 14.5 ft. Deepest at riffle crest but 13 ft down past River Lodge Van Duzen Mouth 7 ft. Deep area restricted. Very poor holding habitat. Weymouth Bluffs 17.5 ft. Large area of deep water.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 7

Table 3. October 11, 2014 dive count data. SH = steelhead, Half_Lb = steelhead <20”. Pool Adult Chinook Jacks Adult_SH Half_Lb Coho Twelfth Street 1646 466 52 87 0 Boxcar 185 55 4 6 0 Drake 80 35 6 2 0 Totals 1911 556 62 95 0

Figure 7. Pool depths of the Weymouth Bluffs Pool on the main Eel River as measured by ERRP 9/17/14 habitat survey overlain on a Google Earth Map image from September 2013.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 8

Figure 8. Lower Eel River October 11, 2014 dive count by pool.

Figure 9. Lower Eel River early October dive results from 2010 to 2014 .

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 9 Solo/Small Team Dive Observations: On November 9, we counted over 800 Chinook salmon in three pools from the mouth of Outlet Creek to below the Middle Fork at Dos Rios. We estimated 250 Chinook salmon at the mouth of Outlet Creek, 75 in a pool half way between Outlet Creek and Dos Rios, and 500 in the convergence pool below the Middle Fork. Conditions were excellent for the November 11 reconnaissance dive at Alderpoint on the main Eel and the South Fork Eel at Tooby Park near Garberville. However, we saw no Chinook salmon. Instead there were thousands of pikeminnow in the community swimming hole in Alderpoint, including numerous large adults.

On November 10 Dennis Halligan saw no Chinook salmon in any pool from the mouth of the Van Duzen to Fernbridge, except in the 12th Street Pool, where he saw 60-70 fish. Two days later on November 12, a small ERRP dive team of six observed approximately 300 adult Chinook salmon, 200 jack salmon, and seven sturgeon in the 12th Street Pool, including a white sturgeon that was video documented. A full dive team was not available and many salmon were likely missed as a result, so the count should be considered a minimum estimate.

Migration Observations: Observations of migrations are in database form as Attachment B. Observations were relayed verbally or via email, and very useful photographs and video were also provided (Figure 10). ERRP also video and photo documented holding and migrating Chinook salmon (Attachment C).

Figure 10. Large group of Chinook salmon in pool at Dos Rios. Photo by Cathy Warren. 11/05/15.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 10 Spawning: The following is a summary of observed 2014-2015 Chinook salmon spawning in the Eel River sub-basins. An full index of ERRP reports is in Attachment C.

Upper Eel River: Some Chinook salmon were spawning in the main Eel River between Outlet Creek and Dos Rios on November 9 (Figure 11), but many more held in the nearby deep pools. A day later Greg Byers saw the first Chinook at Hearst further upstream, although far fewer fish than in recent prior years. Chinook salmon entered Outlet Creek after November 19-23 rainfall and spawning was noted on November 25 near the gravel plant off Highway 162. Chinook also ascended into the headwater Outlet Creek tributaries above Willits, including Baechtel, Broaddus and Willits creeks where ERRP volunteers reported spawning into early December.

Chinook salmon were first able to enter Tomki Creek around November 23. While spawning was widespread, SEC weekly surveys from November 11, 2014 through early January 2015 found a total of only 59 carcasses, 49 live fish and 12 redds. The survey of the reach of the Eel River below Tomki Creek found 3 carcasses, 39 live fish and three redds. (See Attachment D). On December 10, we observed Chinook salmon spawning within the PVP at the mouth of Benmore Creek, about three miles below Scott Dam. There were no Chinook salmon spawning in Soda Creek on that date, but Chinook were staged at the mouth.

South Fork Eel: No Chinook salmon spawning was documented in the South Fork, below Leggett. Instead spawning was concentrated in the upper main South Fork to above Branscomb and all over the Ten Mile Creek watershed. Early run Chinook salmon spawned in Ten Mile Creek above Grubb Creek on November 17, despite very low flows. A week, it rained, allowing migration and spawning in the headwater tributaries above Laytonville, including Cahto Creek where there were a good number of spawners.

Figure 11. Spawning Chinook salmon on redd above riffle just below Outlet Creek on November 9, 2014.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 11 Salmon were spawning in the Main South Fork, below Highway 1, on November 8 and spawning continued there for ten days. Chinook salmon were also observed actively spawning at Big Bend Lodge in South Leggett on November 18, when we counted 28 live Chinook salmon and six redds, in a quarter mile reach. ERRP volunteer John Evans also noted a second wave of fresh fish spawning there in early December.

Downstream on the South Fork at Cedar Creek, no spawning was documented on November 18, but Chinook were spawning actively above and below the mouth of the creek on November 24. In the upper South Fork Eel River, adult fish were seen spawning near the mouth of Jack of Hearts Creek and entering the creek in the first week in December. However, whether these fish were coho or Chinook could not be determined.

In late December, salmon were spawning in Bull Creek tributaries and Sprowel Creek. No redds or fish in were noted during surveys of Bear and Chadd creeks on New Year’s Eve day. Extensive citizen surveys of Salmon Creek in late December found no live fish, carcasses or signs of redds (Keegan 2015). No new redds, carcasses or live fish were documented in upper South Fork Eel River tributaries on February 14-15 (See Attachment C for link to reports).

Van Duzen River: Spawning Chinook salmon were observed and video documented on November 11 just upstream of Grizzly Creek State Park in the Van Duzen River. This is the furthest downstream location where spawning could be confirmed. No spawning was noted at Swimmers Delight or at Shakefork Farm. Many fish passed upstream of Goat Rock Falls and extensive spawning was reported in the Rainbow Bridge area, at Bridgeville, and upstream into Little Larabee Creek. Although water clarity was not sufficient to see mainstem Van Duzen River spawning on November 20, we did see a Chinook salmon carcass in Little Larabee Creek. At least two dozen late fall Chinook were noted spawning three miles up Grizzly Creek on December 6.

Middle Fork Eel River: In the , the upper limit for early arriving Chinook salmon was approximately five miles below the Black Butte River on November 11. With higher flows later in November, fish were seen spawning in the Middle Fork near the Eel River Guard Station, in the Black Butte River, in Williams Creek, and up Mill Creek to above the town of Covelo.

Van Arsdale Fish Station Return: Chinook salmon entered the PVP starting on November 20 and the migration ended the week of December 21, although it tapered off sharply after December 7 as flows increased. A total of 584 Chinook salmon, including 290 females, 228 adult males, and 65 jack salmon were counted. Figure 12 shows VAFS returns dating back to 1946, including 2014-2015. A total of 217 steelhead passed VAFS, with 79 males and 138 females.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 12

Figure 12. Chinook salmon returns to Van Arsdale Fish Station on the upper Eel River from 1946-2014. Data supplied by the CDFW and SEC.

Discussion

A great deal was learned through this monitoring project about Chinook salmon behavior, the quality of their holding and spawning habitat, and about other fish species encountered during dives or observed and documented by volunteers.

Dive Results: The highest ever early October dive count of 2,467 Chinook salmon was because passage above the three pools surveyed was not possible before the dive; therefore, we were able to count the entire early portion of the run. In previous years since 2012, the first increase in flow allowed an unknown number of adult fish and jack salmon to migrate upstream and avoid ERRP counts. The October 11 dive likely under-counted fish in the Drake Pool because a key dive lane along the bank was occupied by an inexperienced diver who saw a school of Chinook salmon pass but was unable to estimate their number.

HRC and ERRP are confident that surveys of the 34’ deep lower High Rock Pool, and the 36’ deep Holmes Bluff Pool, on November 19 did not substantially under-estimate Chinook salmon abundance. Experienced diver and ERRP volunteer Eric Stockwell was able to descend to 30 feet. However, if there had been large schools, a diver without scuba tanks cannot stay down long enough to count them.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 13 The 12th Street Pool takes at least 10 divers to get an accurate dive estimate, and a team size of 12- 15 is optimal. With only six volunteers on November 12, ERRP was able to get some useful data on Chinook salmon abundance and adult sturgeon, and take some videos of sufficient resolution to identify a white sturgeon. Collection of even better data might have resulted, had the team also included a scuba diver.

Total Run Estimate: ERRP estimates the early portion of the run migrating upstream before October 31 as two to four times the October 11 count, or 5,000 to 10,000 Chinook salmon. We are comfortable that this is not a major under-estimation because of the modest number of fish seen by upstream observers. Volunteers noted mostly small groups migrating, which contrasts with late 2012, when hundreds per hour passed places like Alderpoint, for several days. Dives and angler reports confirmed that the second pulse of Chinook in early November 2014 was also far less than in 2012. For example, in 2012, ERRP and HRC found more than 8,000 Chinook salmon holding in 10 pools below Dyerville from November 8-11. By contrast, in 2014, ERRP and HRC counted about 1,500 fish in five pools from November 12-19, although the 12th Street Pool November 12 dive was an under-estimate. According to fishing guides, Chinook salmon held only in extremely deep pools of the lower Eel River during this low water period. There were fewer than 20 of these pools downstream of Dyerville. Also, not all deep pools held Chinook salmon, as indicated by the lack of fish in the lower High Rock Pool during the November 19 dive. ERRP’s estimate of 2,500 to 5,000 fish in the second portion of the run is based on 10 pools, holding from 250-500 salmon.

Historic data from CDFW Benbow Dam fish ladder counts show that half the Chinook salmon passed before December 1, and half after, which suggests a late run of 7,500-15,000. However, given that the strength of the run seemed to be fading later in the season, we are making a conservative estimate of 5,000 fish for the late portion of the run. The foregoing provides the basis for an ERRP 2014-2015 total run-size estimate of 12,500 to 20,000 Chinook salmon (Figure 13).

Figure 13. USGS flow data for the Eel River overlain with ERRP estimates, including total run-size estimate.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 14

Significance of VAFS Returns: The 584 Chinook salmon that passed upstream of the VAFS to spawn within the PVP was an increase from 2013-2014, when only 168 Chinook salmon did so. The 2014 total, however, pales by comparison to VAFS returns of 2010 (2,315), 2011 (2,436), and 2012 (3,461), which were successive records. The lesser return this year reflects decreased overall strength of the run, but also flow timing.

Because of a lack of early flows sufficient for migration, a very large amount of Chinook salmon spawning took place on the main Eel River further downstream, which decreased totals passing VAFS. The main Eel River from below Tomki Creek downstream to Dos Rios provides excellent spawning substrate for Chinook salmon, with ample cobble and gravel of appropriate size, and low fine sediment. Also, juvenile Chinook salmon fry can choose quiet edge waters of the unconstrained channel downstream of the PVP for rearing.

By contrast, spawning habitat within the PVP is compromised due to lack of gravel recruitment below Scott Dam. Also, there are no slow gravel bar edges in the main Eel River between the dams where Chinook salmon fry can move when high flows occur because encroaching riparian within the project disconnects the channel from the floodplain. Therefore, the number of fish passing the VAFS may not translate into improved production of Eel River Chinook salmon fry.

Only 217 steelhead passed VAFS in 2014-2015, while more than 600 adults returned in 2013-2014. Just as with Chinook salmon, steelhead returns to VAFS may be as much or more a product of flow timing than abundance. Steelhead habitat within the PVP also needs enhancement.

Jack Salmon Return Rate: Of the 3,957 Chinook salmon counted by ERRP and HRC in 2014, a total of 1011were jack salmon or two year old males. This indicates about a 26% occurrence of jacks, which are the progeny of the 2013-2014 spawn and suggests a high survival rate last year. Jacks are usually part of the earliest portion of the run and the lower 11% jack rate at VAFS likely reflects the late flow window for migration and that a higher proportion of jacks spawned downstream of the PVP and VAFS. The ranges of recent jack returns are 32% in 2010, 50% in 2011, 15% in 2012, and 20% in 2013.

Potential Survival of 2014-2015 Eel River Chinook Salmon Brood: Although there are still many unknowns in terms of the survival of juvenile fish from the 2014-2015 brood, egg and alevin survival was likely high. Chinook salmon eggs generally hatch in 30 days in typical Eel River winter water temperature conditions, and their larvae or alevin reside under the gravel for an equal period of time before emerging as fry. Chinook in 2014-2015 spawned mostly in upper stream reaches that are generally more intact and less likely to experience bedload movement or sedimentation that smothers eggs or blocks fry emergence. Also, no storm event during the season was likely of sufficient intensity or duration to trigger bed scour and decrease egg or alevin survival.

Eel River Chinook salmon fry likely began emerging beginning in mid-January, with those from later spawning out of the gravel by mid-March. Late emerging or slow migrating fry may have faced increased predation by the non-native pikeminnow (Figure 14). The degree of predation remains unknown, but small rain storms in the first days of April 2015 caused the Eel River to rise and turbidity to increase at least for a few days. Odds of migrating fry survival also depend on pikeminnow population levels, which need further study.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 15

Figure 14. ERRP Volunteer Coordinator Pat Higgins with 17 inch female pikeminnow that took a spinning lure just below McCann on the main Eel. Photo courtesy of Eric Stockwell and Loleta Eric’s Guide Service. 3/13/15.

Ocean Survival: One of the major reasons for the resurgence of Eel River Chinook salmon has been highly productive ocean conditions associated with a favorable deflection of atmospheric and ocean currents, known as the Pacific decadal oscillation (PDO)(Hare et al. 1999). As of 2012, it appears that the PDO has switched to the north, triggering a greater likelihood of northern California droughts and the threat of poor ocean productivity in the California Current where Eel River salmon feed. The National Oceanic and Atmospheric Administration (2015) predicts a 70% likelihood of a strong El Nino event in 2015, which could bring with it much needed rainfall, but could also dramatically decrease the growth and survival of the 2014-2015 Eel River Chinook salmon brood in the ocean. Ocean fishing has the potential to decrease Eel River Chinook salmon escapement, but recent high returns have come in some years where there were extensive sport and commercial fisheries. Closure of ocean fisheries, which may occur if Central Valley and Klamath- Trinity River stocks decline in response to drought, would likely result in an increase in Eel River Chinook salmon escapement.

Sturgeon: The number of sturgeon seen in the estuary and lower Eel River would suggest that there are substantial food resources in both environments. The estuary is continuing to recover from past flood events and productivity is likely increasing as wetlands are reconnected, such as by the lower Ecosystem Restoration Project. The food base in the main Eel River may also be increasing as the benthic fauna increase in response to bed recovery and lesser fine sediment. High densities of the non-native snail Radix auricularia in the 12th Street Pool were observed on November 12, coincident with the confirmed presence of seven sturgeon, including a white sturgeon. The snail appears to be experiencing rapid population growth as it explores new habitat, but the degree to which they are providing forage for sturgeon is unknown. Some of the adults sited may also be staging for spawning runs, although white sturgeon are not known to spawn in the Eel.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 16 Sacramento Pikeminnow: Very large numbers of adult Sacramento pikeminnow were observed in the lower Eel River in 2013 and 2014, unlike from 2010-2012 when they were scarce below the mouth of the Van Duzen River. These fish are likely moving down in response to diminished tributary habitat due the drought. Also, water temperatures have also increased in the lower Eel River associated with low flows, and pikeminnow prefer warm water. Observations of very large numbers of pikeminnow, including large adults, on November 11 in the large pool in Alderpoint contrasts with August and October 2014 dives when there were almost none there. Large pikeminnow adult concentrations appear to be restricted to pools with sufficient depth and complexity, such as large wood, so they can avoid otters. ERRP will be publishing a recap of pikeminnow reconnaissance in May 2015.

Sacramento Suckers: Very large schools of native Sacramento suckers were sited at three locations. ERRP Volunteer Cathy Warren photographed dozens of adult suckers migrating upstream above the mouth of Outlet Creek on November 5 (Figure 15). In addition to the suckers of 12-16” migrating in shallow water, there appeared to be much larger and older suckers staging in the pool off the mouth of the creek.

On November 19, a school of suckers of 12-14” in length that was likely at least 1,000 fish passed under divers in the lower Dyerville Pool below the South Fork. A smaller school of a few hundred was also seen on the same day in the lower High Rock Pool. There was concern regarding the impacts of the pikeminnow introduction on native suckers, but it appears that this species is making a comeback.

Figure 15. School of migrating Sacramento suckers on the main Eel River just upstream of Outlet Creek, with one northern pikeminnow at upper left. Photo by Cathy Warren.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 17 Eel River Chinook Salmon Extinction Risk: As recently as 2010, some very well respected scientists characterized the Eel River Chinook salmon population as being at a dangerously low level and at high risk of extinction in a time frame of 50 years. Their concerns were based on low VAFS returns and CDFW tributary carcass and redd count data; however, these indicators were not representative. Lower Eel dive counts and basin-wide tracking have been able to ascertain that Chinook salmon population levels are remaining above 10,000 since at least 2012, which is the highest level of abundance documented since USFWS (1960) surveys from 1955-1958. The widespread distribution and levels of high abundance indicate that the short term risk of extinction is low, based on principals of analysis similar to Rieman et al. (1993).

The main factor driving Chinook salmon recovery is the improvement of main Eel River spawning gravels. Record amounts of sediment from the 1964 flood filled pools and buried the streambed, but fine sediments have winnowed with high flows over the following decades, and in particular high winter and spring flows from 1995 to 2012. Excellent spawning habitat extends for hundreds of miles of main Eel River channels, including from below Van Arsdale Dam to Dyerville, in the Middle Fork Eel and Black Butte River, and the upper Van Duzen River. The South Fork Eel River also has optimal spawning gravels from Ten Mile Creek to Piercy.

The fish spawning in all these areas constitute sub-populations and in aggregate all are part of a larger metapopulation. The high production of juveniles and survival and growth in the ocean has created enough spawners to fully colonize the entire basin up to the waterfalls that are their historic natural boundary of migration. Some former highly productive Chinook salmon streams had little or no spawning activity in recent years, which gives rise to concern that local populations are going extinct. In fact, Eel River Chinook salmon know to avoid perturbed stream because they have co- evolved with the geologic upheavals of great earthquakes, endured massive fires, and survived numerous major floods. Immediately after catastrophic events, some streams would be overwhelmed with sediment and huge jumbles of large wood, and fish would avoid them for decades or longer, similar to the findings of Reeves et al. (1995).

After fine sediment flushed, fish would return to spawn and rear in habitat that had improved in complexity and carrying capacity.

Chinook migrating up the South Fork Eel River may currently pass impaired tributaries, like Salmon Creek, but they would enter in the future, if sediment levels dropped sufficiently.

At left: Salmon Creek during December 2014 spawner survey. Photo by Kyle Keegan.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 18 Conclusion

After three years of doing our survey, ERRP is comfortable that the short-term risk of loss of Eel River Chinook salmon is low. Main Eel River channels have more abundant spawning gravel now that fine sediment deposited by the 1964 flood has been flushed. More than 10,000 Chinook salmon spawn annually and the surplus of spawners generated by these rejuvenated main river channels is distributed throughout the Eel River basin to historic upstream boundaries.

However, there are signs that some Eel River tributaries are losing their ability to support Chinook salmon. Each watershed has a threshold of disturbance that, if exceeded, causes an ecological unraveling that can include loss of Pacific salmon species. In ecology, this threshold is referred to as a “tipping point” (Marten 2005). Large Eel River sub-basins currently past or approaching their tipping points with regard to their ability to support Chinook salmon are Tomki, Outlet, Salmon, and Ten Mile creeks. If erosion prevention is implemented and other sources of pollution lessened, Chinook salmon could re-colonize them rapidly.

A sediment study of Salmon Creek is needed to understand the origin and routing of sediment currently impairing Chinook salmon spawning habitat, despite extensive previous restoration and erosion control efforts. Data also need to be collected in Salmon Creek and elsewhere to gauge habitat trends, so that the community can better understand how various restoration strategies are working. Kier Associates and NMFS (2008) provide a number of scientific methods for tracking salmon habitat conditions.

The 2014-2015 Chinook run started with the lower Eel River extremely low and disconnected, and there was potential for a Chinook salmon fish kill. More needs to be done to improve Chinook salmon adult holding habitat in this reach, similar to recommendations made previously by ERRP. In particular, the Worswick Pool above Fernbridge needs to be deepened using bioengineering to prevent further bank erosion, and to create an adult Chinook salmon holding pool immediately above tidewater. Restoration is also needed in the lower reach of the Van Duzen River above its convergence with the Eel River to reduce fish stranding risk and to help advance channel recovery. Also, spawning and rearing habitat between Scott Dam and Cape Horn Dam in the PVP remain impaired, and restoration should take place there to improve survival of Chinook salmon eggs and juvenile fish.

Because there is a possibility for substantial fluctuations in the Eel River Chinook salmon population, ERRP should continue dive surveys and basin-wide tracking of fall Chinook in 2015- 2016 for trend monitoring purposes. To reduce stress on fish and improve count precision, ERRP will experiment with dive formations that open gaps to encourage fish to pass upstream, instead of pushing them downstream into shallower water. In deep pools, especially during periods of high Chinook salmon presence, ERRP will employ scuba divers to check on size of schools at depth. ERRP hopes to work together with CDFW, the Tribes, and interested non-profit organizations to explore the strategic use dual frequency sonar technology (DIDSON) for short durations when flows rise rapidly to quantify mass migrations.

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 19 References

Collison, A., W. Emmingham, F. Everest, W. Hanneberg, R. Martston, D. Tarboton, R. Twiss. 2003. Phase II Report: Independent Scientific Review Panel on Sediment Impairment and Effects on Beneficial Uses of the Elk River and Stitz, Bear, Jordan and Freshwater Creeks. Independent Science Review Panel performed analysis on retainer to the North Coast Regional Water Quality Control Board, Santa Rosa, CA. http://www.krisweb.com/biblio/hum_swrcb_collison_2003_phaseiiisrp.pdf

Garman, C. 2012. Amended 2012 Butte Creek Spring-run Chinook Snorkel Escapement Survey. Memo from environmental Specialist Clint Garman to Joe Johnson, Senior Environmental Specialist. CDFW, Chico, CA. 5 p.

Gibbs, E. 1964. Letter from CDFG Fisheries Biologist Earl Gibbs to CDFG Fisheries Management Supervisor Elton Bailey, re: Benbow Dam, Fish Passage. Dated March 13, 1964. CDFG, Sacramento, CA. 4 p.

Halligan, D. 1998. Final Report – 1997 Fisheries monitoring program for gravel extraction operations on the Mad, Eel, Van Duzen, and Trinity Rivers. Natural Resources Management Corporation, Eureka, California.

Hare, S. R.; Mantua, N. J.; Francis, R. C. 1999. Inverse production regimes: Alaska and the west coast Pacific salmon. Fisheries, Vol. 24 (1): 6-14.

Keegan, K. 2015. Autopsy of a Pending Local: The Tragedy Of Mono-Economies and Why Outside Regulation Alone Won’t Save Our Salmon. Published in Forest and River News, Spring 2015 Edition, Trees Foundation, Garberville, CA. p 3-10. https://go.treesfoundation.org/wp-content/uploads/2014/05/FRNSpring2015.pdf

Kier Associates and National Marine Fisheries Service (NMFS). 2008. Guide to Reference Values used in the Southern Oregon / Northern California Coho Salmon Recovery Conservation Action Planning (CAP) Workbook. National Marine Fisheries Service, Arcata, CA. 29 p.

Marten, G.G. 2005. Environmental Tipping Points: A New Paradigm for Restoring Ecological Security. Journal of Policy Studies (Japan), No.20 (July 2005), pp. 75-87.

McCullough, D. 1999 . A Review and Synthesis of Effects of Alterations to the Water Temperature Regime on Freshwater Life Stages of Salmonids, with Special Reference to Chinook Salmon. Columbia Intertribal Fisheries Commission, Portland, OR. Prepared for the U.S. Environmental Protection Agency Region 10. Published as EPA 910-R-99-010.

National Oceanic and Atmospheric Administration. 2015. ENSO: Recent Evolution, Current Status and Predictions. February 2, 2015. NOAA Climate Prediction Center (enso_evolution- status-fcsts-web.pdf)

Eel River Recovery Project: Final Report 2014-2015 Fall Chinook Salmon Monitoring May 2015 20 Reeves, G.H., L.E. Benda, K.M. Burnett, P.A. Bisson, and J.R. Sedell. 1995. A Disturbance- Based Ecosystem Approach to Maintaining and Restoring Freshwater Habitats of Evolutionarily Significant Units of Anadromous Salmonids in the Pacific Northwest. American Fisheries Society Symposium 17:334-349, 1995.

Rieman, B., D. Lee, J. McIntyre, K. Overton, and R. Thurow 1993. Consideration of Extinction Risks for Salmonids. As FHR Currents # 14. US Forest Service, Region 5. Eureka, CA. 12 pp. www.krisweb.com/biblio/gen_usfs_riemanetal_1993_fhr14ri.pdf

Steiner Environmental Consulting. 2015. Upper Eel River Salmon Surveys and Ladder Count. January 2015. Excel database containing SEC spawner survey data and Van Arsdale Fish Station CDFW Chinook salmon counts. SEC, Ukiah, CA.

U.S. Fish and Wildlife Service. 1960. Survey of Chinook salmon spawning habitat in northwestern California. Natural Resources of Northern California Report, US Fish and Wildlife Service, Pacific Southwest Field Committee, Sacramento, CA. 104 p.

Yoshiyama, R. and P.B. Moyle. 2010. Historical review of Eel River anadromous salmonids, with an emphasis on Chinook salmon, coho salmon and steelhead. Produced for California Trout with funding from Friends of Eel River. Center for Watershed Sciences, U.C. Davis. 132 p.

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