Spatial distribution of Chinook Salmon (Oncorhynchus tshawytscha) spawning in the Elwha River, Washington State during dam removal and early stages of recolonization (2012-2019) Adult Chinook in Lower Elwha River 2019 (John McMillan photo) Submitted to Olympic National Park by the Lower Elwha Klallam Tribe In partial fulfillment of the agreement for performance of monitoring pursuant to the National Park Service’s Chinook and Steelhead Monitoring Plan for the Elwha River Authors: Mike McHenry1, George Pess2, and Joe Anderson3 1. Lower Elwha Klallam Tribe, 760 Stratton Road, Port Angeles, WA 98363 2. NOAA-NWFSC, 2725 Montlake Blvd East, Seattle, WA 98112 3. Washington Department of Fish and Wildlife, PO Box 43200, Olympia, WA 98504-3200 1 Executive Summary The distribution of spawning nests, or redds, is an important metric to assess the recolonization success by adult salmonids in newly available stream habitats. We assessed the spatial distribution of adult Chinook salmon spawning in the Elwha River and selected tributaries from 2012 to 2019, a period in which two hydroelectric dams were removed. Chinook salmon redds were located by visual surveys conducted at or near the peak of spawn timing in mid- to lateSeptember. Surveys were conducted in mainstem, side-channel, and large tributary habitats for all years from the mouth of the Elwha River upstream to Glines Canyon Dam site at Rkm 21.7 at flows that ranged from 7.0 cubic meters per second (cms) to 11.9 cms. In 2014-2015 additional surveys were conducted immediately upstream of Glines Canyon Dam to Rica Canyon (Rkm 23.4). As Chinook salmon recolonized further upstream, new survey reaches were added in 2016-2019 that included the uppermost watershed to near Chicago Camp at Rkm 61.7. Redds were geo-referenced using GPS units, and live and dead adult Chinook salmon were enumerated. Surveys in 2012 and 2013 were limited by poor visibility (72 FNU and 45 FNU average turbidity, respectively) in the Lower Elwha River downstream of the Elwha Dam site. Conversely, surveys in 2014-2019 were conducted during very low turbidities (5.0 FNU, 0.8 FNU, 5.5 NTU, 2.3 FNU and 5.0 FNU average turbidity, respectively). In 2019, a large number of Chinook salmon adults returned to spawn in the Elwha River (escapement estimate currently not available). A total of 614 (201 males/410 females) surplus hatchery adult chinook were relocated upstream to a release point just above the ONP entrance. A total of 1,673 Chinook redds and 2,191 adults (937 live/1254 dead) were observed during peak spawning surveys in 2019. The majority of redds were again located in the Middle Elwha (65.7%). In 2019, the percentage of the total redds observed upstream of Glines Canyon decreased by more than half from 2018 from 13.2% to 6.2% and the majority of those were observed in the former Mills Reservoir including Boulder and Cat Creeks. Only 6 Chinook salmon redds and 17 adults were observed above Rica Canyon in 2019, compared to 45 adults and 16 redds observed in 2018. One redd and two adult Chinook were observed above the Grand Canyon of the Elwha during snorkel surveys in the upper watershed conducted in early September. Also of note is the large number of redds observed in Indian Creek (215) and Little River (124) in 2019. Both were records since the initiation of the project. The most obvious trends in terms of the spatial distribution of Chinook salmon redds has been an increasing number of redds observed initially in the Middle Elwha, and more recently in the upper Elwha between Glines Canyon and Rica Canyon. Fish passage conditions at Glines Canyon were initially unfavorable for fish passage immediately following dam removal (2014) until after consecutive years of blasting were completed to remove hydraulic jumps in 2015 and 2016. In 2016-2019, the first significant numbers of Chinook salmon colonized the area above 2 Glines Canyon with the majority of redd observations occurring on the former Mills Reservoir surface. Some of this increase can be attributed to the relocation of adults in 2018 and 2019. Although still early in the recolonization process, relatively few adults have volitionally accessed the upper watershed above the Grand Canyon of the Elwha. Actively transporting adults would place more fish into suitable upriver habitats potentially accelerating the recolonization of habitats high in the watershed. Some believe this carries risks of undermining natural ecological and genetic processes that may be important for successful numerical and spatial expansion. Others think that the level of risk is low in areas where Chinook are currently in extremely low densities, and if progeny of adults relocated to the upper watershed are not genetically fit they will simply not survive. Introduction The removal of two hydroelectric dams on the Elwha River represents the largest intentional dam removal completed to date in the world. Located at Rkm 7.9 and 22, the 32 m tall Elwha Dam (completed in 1913) and 64 m tall Glines Canyon Dam (completed in 1927) were identified for removal under the Elwha River Ecosystem and Fisheries Restoration Act of 1992 (Elwha Act). The goal of the Elwha Act is to restore the Elwha River ecosystem and associated anadromous fish populations through dam removal, sediment management, revegetation, and the conservation and amplification of native salmon populations. The long-term goal is to establish self-sustaining, natural populations of Pacific salmon and steelhead, sufficiently abundant to support meaningful harvest, reducing and ultimately eliminating hatchery supplementation over time (Ward et al. 2008). To help guide this process, the Elwha Monitoring and Adaptive Management (EMAM) plan was developed for federally listed populations of Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) (Peters et al. 2014). This document, and the Hatchery Genetic Management Plans (HGMP) for the WDFW and Tribal hatchery programs, suggests the use of adaptive management targets to inform management actions for the recovery of the populations. The HGMP targets differ slightly from the EMAM targets, so for this document, “triggers” or “targets” refers to values in the EMAM unless stated otherwise. The EMAM provides performance indicators coupled with management triggers to guide project managers through four stages of recovery including: 1) preservation, 2) recolonization, 3) local adaptation, and 4) viable natural population. Performance indicators used in the EMAM are based upon the general Viable Salmon Population (VSP) metrics including abundance, productivity, spatial distribution and diversity (McElhany et al. 2000). For Elwha River Chinook salmon, abundance is being estimated using SONAR (Denton et al. 2013, 2014, 2015, 2016, 2017). Productivity metrics are being assessed using a combination of abundance estimation by smolt outmigration monitoring (McHenry et al. 2016, 2017) and adult to adult cohort 3 reconstruction (Weinheimer et al. 2016, 2017). Spatial distribution on the Elwha is being assessed using a combination of visual redd surveys (foot, snorkel, boat, and aerial), radiotelemetry, and eDNA techniques (Laramie et al. 2015). For diversity, Chinook salmon monitoring efforts focus on adult migration timing (SONAR) and the expression of stream-type juvenile life-histories. Elwha River salmon populations were spatially limited to approximately 8.0 km of habitat below Elwha Dam for over a century. The removal of the Elwha and Glines Canyon dams has allowed for the recolonization of formerly occupied habitats. However, it is uncertain how quickly recolonization and the establishment of self-sustaining spawning populations will occur. Prior to dam removal, it was predicted that Chinook salmon were expected to recolonize in the Elwha upstream of Carlson Canyon at Rkm 56.0 over a period of 5 to 7 generations (DOI 1995). On the Cedar River, Washington, a much shorter system than the Elwha River, following the construction of fish passage facilities at Landsburg Dam, Chinook salmon spawned as high as 18 km above the facility the first year they were provided access, however the majority of spawners were concentrated 6 km above the facility (Burton et al. 2013). Additionally, on the Elwha River, dam removal has not recreated the exact physical habitat conditions that existed prior to dam removal or prior to dam construction. Since dam removal, the channel is stabilizing and revegetating in those reaches impacted by dam removal. However, other natural or human-caused barriers may ultimately limit the distribution of different salmonid species within the watershed. The spatial distribution of Chinook salmon also potentially affects other VSP parameters such as life history diversity (Beechie et al. 2006). In the Puget Sound region, Chinook salmon populations in snowmelt-dominated areas, such as the Elwha River, typically contain a higher proportion of the stream-type life history (juvenile residence ≥1 year in freshwater), and have older age structure than Chinook Salmon populations in rainfall-dominated areas which produce primarily zero aged migrants (Beechie et al. 2006). Furthermore, in Puget Sound, the fraction of Chinook salmon genetic differentiation that can be attributed to life history characteristics is relatively small, compared to the Columbia Basin (Waples et al. 2008). This suggests a strong role for environmental conditions in stream versus ocean-type juvenile rearing strategies of Puget Sound Chinook salmon. Thus, to the extent that spawning in snowmelt dominated headwater reaches will promote stream-type life histories, allowing some portion of the extant Chinook salmon population to recolonize habitats above the dam sites on the Elwha may result in the re-expression of this suppressed life history characteristic. Dam construction, which began in 1910, blocked the vast majority of the spawning habitat in the Elwha River basin, including all of the snowmelt dominated areas typically associated with stream-type life histories. Chinook salmon persisted in the lower river and were maintained by 4 a large hatchery supplementation program initiated by WDFW beginning in the 1930’s and maintained to the present (Winter and Crain 2008). This program uses broodstock directly descended from the remnant Elwha Chinook salmon population, with relatively minor contributions from other rivers over the years (Myers et al. 1998). From 2010-2017, > 90% of Chinook salmon returning to the Elwha River basin were hatchery origin (Anderson et al. 2015; Weinheimer et al. 2017). EMAM (Peters et al. 2014) has established a recovery goal of 100% natural origin spawners for a self-sustaining population of Elwha River Chinook salmon. “Rewilding” this hatchery-dominated population represents a significant challenge for the overall Elwha project. Dam removal was initiated in the fall of 2011 and by the spring of 2012, Elwha Dam had been removed1. Glines Canyon Dam was removed by August 26th, 2014, and the first Chinook salmon above the Glines Canyon Dam site was reported approximately 10 days later on September 9 th, 2014. Several weeks later, large boulders fell from the canyon walls and created vertical drops of 12-15’ through the entrance to Glines Canyon. It was feared, and later confirmed, that these boulders created blockages to upstream migrating salmon. In the fall of 2015 and 2016, selective blasting was conducted to reduce vertical drops and increase effective stream width through the rock fall. Those treatments have been partially successful and the vertical drop through the reach has been reduced to approximately 6’ (Personal Communication, Andy Ritchie, Olympic National Park). In order to collect information on the spatial extent of Chinook salmon spawning, biologists from the Washington Department of Fish and Wildlife (WDFW), Lower Elwha Klallam Tribe (LEKT), Olympic National Park (ONP), National Oceanic and Atmospheric Administration (NOAA), U.S. Fish and Wildlife Service (USFWS), and United States Geological Survey (USGS) initiated a one-day, peak spawning survey event in 2012. This survey event was repeated in 2013 and focused on the areas downstream of Glines Canyon Dam. In 2014-19additional surveys were conducted upstream of Glines Canyon Dam in order to ascertain Chinook salmon passage at Glines Canyon and to document the recolonization of habitat by Chinook salmon. This report summarizes those survey efforts as our objectives were to; 1) map the spatial distribution of Chinook salmon redds, 2) calculate the density of Chinook salmon redds by river kilometer (Rkm), and to compare the relative distribution of spawning Chinook salmon within and between years. 1 During extreme low flows of 2015 it was discovered that the base of Elwha Dam along with a caisson constructed after the initial dam failed in 1912 had actually not been removed. There are currently no plans to conduct further removal activities. 5 Methods One day to five-day spawning ground surveys of the mainstem Elwha River, larger floodplain channels, and several major tributaries were conducted in mid-September from 2012 to 2019 in the Elwha watershed. Survey timing was based on the estimated historical date of peak spawning activity for Elwha River Chinook salmon, approximately September 15 - September 25 (WDFW Unpublished Data). For purposes of the survey, the Elwha River was divided into three broad sections. The Lower Elwha (LE) was defined as the area downstream of Elwha Dam (Rkm 0.0-6.6). The Middle Elwha (ME) includes the reach immediately above the former Elwha Dam, including the former Aldwell Reservoir, upstream to the former Glines Canyon Dam (Rkm 6.619.7). Lastly the Upper Elwha (UE) is defined as the reach above Glines Canyon Dam, including the former Mills Reservoir, Cat and Boulder creeks, upstream to Chicago Camp (Rkm 19.763.4)2. The Lower Elwha3 and Middle Elwha were surveyed in all years, while the Upper Elwha was surveyed in 2016-2019. Supplemental surveys were conducted in the UE in 2014 and 2015, however these only included the former Mills Reservoir area from Glines Canyon Dam upstream to the entrance of Rica Canyon. We did not generally survey any of the major canyon areas of the Elwha River during peak surveys with the exception of Rica Canyon in 2014 and 2015. These include the canyon immediately above Elwha Dam, Glines Canyon, Rica Canyon, Grand Canyon, and Carlson Canyon (Figure 1). Additionally no comprehensive surveys have occurred to date in larger upriver tributaries with the exception of Long Creek in 2018. Each survey reach was originally partitioned using local geographic features or place names that have an associated River Kilometer (Rkm) (Table 1). These reaches were consolidated in 20152019 to simplify data collection (Tables 2 & 3). Individual reach surveys were assigned to two person crews consisting of biologists and biological technicians from the Lower Elwha Klallam Tribe (LEKT), Olympic National Park (ONP) and Washington Department of Fish and Wildlife (WDFW). Additional support was also provided by staff from the United States Fish and Wildlife Service (USFWS), National Oceanographic and Atmospheric Administration (NOAA) and the United States Geological Survey (USGS). Within each survey reach, two person crews conducted standard spawning ground surveys by walking from the upper end of the reach downstream to its terminus (Gallagher et al. 2007), typically with one surveyor on each side of the river. In some years observers also conducted snorkel surveys to collect observations of live 2 3 The actual upper end of survey has varied by years. Please consult Figures 3-10 to determine that end by year. Lower Elwha surveys were unsuccessful in 2012 and partially successful in 2013 due to elevated turbidity. 6 Chinook salmon and associated nests (redds). This was particularly true in 2018 and 2019 where a “riverscape” snorkel survey was conducted in early to mid-September. The surveyors recorded the number of Chinook salmon redds, and live and dead Chinook salmon observed within each survey reach. Opportunistic determination of the sex of live and dead Chinook salmon, jacks (precocious males), visual marks (floy tags or fin clips), as well as presence of pink and sockeye salmon and steelhead was also documented in some years. Redds were identified as disturbed areas in the stream bed where the substrate was overturned (Gallagher et al. 2007). Each redd was geo-located (latitude and longitude) using a Garmin GPS (chiefly model GPSmap 60CSx). Flow levels, turbidity, and suspended sediment concentration levels varied each year (Table 4). Both flow and turbidity levels where highest in 2012, which limited surveys to above the Elwha dam site (Table 5). In 2013, conditions improved to allow for surveys below the former Elwha dam, and 2014 conditions allowed for a full survey from the mouth to just above former Glines Canyon dam (Table 6). Since 2015, turbidity has not been a factor during surveys in any reach. While it is generally true that visual survey techniques are not effective during high flows on the Elwha River because of elevated suspended sediment levels, we have identified a lowdischarge, low turbidity window that corresponds to the period of peak spawning for Chinook salmon. We typically note a general decline in visibility moving in a downstream direction, likely due to the river interacting with stored sediments from dam removal. This was particularly true in the lower Elwha during 2012 and 2013 when turbidity levels were elevated enough through the low flow window to preclude surveys. However, over time survey conditions have greatly improved, enhancing precision of the peak count method. Results The total number of observed Chinook salmon redds increased between 2012 and 2014 from 217 to over 1,310 redds, an increase of 83% (Figure 2). In 2015 and 2016 the number of redds decreased by 28% (937) and 53% (614), respectively, from the peak number observed in 2014. In 2017, the number of redds increased slightly (767) in comparison to the previous year. In 2018 and 2019, we observed the highest number of Chinook redds (1,601 and 1,672 respectively) since the project began (Figure 2). In all years, the majority of Chinook salmon redds were located in the ME above the former Elwha Dam (Rkm 7.5) and just below the former Glines Canyon Dam (Rkm 21.7) (Figures 3-10). It is important to note that visibility was poor in the lower river during 2012 and 2013 thus the number of redds below the former Elwha Dam in those years was likely an under-estimate. Abundance estimates derived from SONAR 7 indicated that Chinook salmon abundance ranged from a low of 2,628 (2016) to a high of over 7,000 (2018) (Figure 12). In 2012, 217 Chinook salmon redds were located, of which 203 (93.5%) were identified upstream of the former Elwha Dam (Figure 3, Table 5). Fifty-two percent of these redds were located either in the mainstem ME or in the former Aldwell Reservoir area (Table 5). Forty-eight percent of the Chinook salmon redds were found in Indian Creek and Little River, two Middle Elwha tributaries unaffected by dam removal turbidity effects (Figure 3). The spatial distribution of Chinook salmon redds in 2012 were clumped in three general areas Rkm 9.8 to 12.2 (Gooseneck to Highway 101 bridge), Rkm 16.5 to 18.0 (Fisherman’s Bend to Rabbit Hole), and the two large ME tributaries (Indian Creek and Little River) (Figure 3). In 2013, additional survey reaches were added in the LE due to better visibility (Figure 4, Table 6). A total of 765 chinook redds were identified, 79% (602 out of 765) of which were observed above the former Elwha Dam location (Table 6). The distribution of mainstem vs. tributaries changed in 2013, with the vast majority of Chinook salmon redds (85%) being identified in the mainstem and 15% being identified in Little River, Indian Creek, and Hughes Creek collectively (Figure 4, Table 6). Over one quarter of the Chinook salmon redds, 27% (162 out of 602), were located in the 1.1 km immediately below Glines Canyon Dam in 2013. Fifty-eight percent (347 out of 602) of the Chinook salmon redds were located within 5.0 km of the Glines Canyon Dam site (Table 6). Glines Canyon Dam was still being removed in 2013 and was not passable to anadromous fish. In addition to Chinook salmon, surveyors reported one pink salmon and three sockeye upstream of Elwha Dam. Below the former Elwha Dam site, Chinook salmon spawning activity was only documented upstream of Rkm 3.9 due to deteriorating visibility in the reaches further downstream (Figure 4, Table 6). The reach from the Highway 112 Bridge to the weir at Rkm 5.5 (within lower Elwha) had the second highest density of Chinook salmon redds recorded in the survey (Figure 4, Table 6). In 2014, visibility was excellent and survey reaches from the previous year were used to conduct a river wide survey (Figure 5, Table 7). A total of 1,310 Chinook salmon redds were located and identified, of which 62% (811 out of 1,310) were located in the middle Elwha, upstream of the Elwha Dam and below the former Glines Canyon Dam (Figure 5, Table 7). The distribution of mainstem vs. tributaries changed again in 2014 relative to the two previous years: 95% of the Chinook salmon redds were located in the mainstem, while only 5% were identified in Little River, Indian Creek, and Hughes Creek (Figure 5, Table 7). Only one redd was observed in Little River. The low number was likely a result of low attraction flows, as the mouth of Little River joined the Elwha River across a broad gravel bar that had flow only several centimeters deep. Over one quarter of the Chinook salmon redds in the middle Elwha (30%, 241 out of 812) were located in the 1.1 km immediately below Glines Canyon Dam in 2013, 8 while over 60% (61%, 496 out of 812) of the Chinook salmon redds were located within 5.0 km downstream of the Glines Canyon Dam site (Figure 5, Table 7). Glines Canyon Dam was still being removed in 2014, a process that was not complete until August 26th. However, it should be noted that small numbers of Chinook salmon were observed above Glines Canyon in 2014. During the first week of September, Mel Elofson, a member and employee of the Lower Elwha Klallam Tribe, reported seeing a Chinook salmon just above the Glines Canyon site. On September 9, ONP staff snorkeled from Rica Canyon downstream to the Glines Canyon Dam and visually identified 3 adult Chinook salmon. A subsequent survey on September 22 identified a single Chinook salmon redd, which was geolocated by ONP. On September 30 an additional Chinook salmon redd survey was conducted in the Geyser Valley (Rica Canyon to Dodger Point) and no Chinook salmon or Chinook salmon redds were located. It should be noted that a citizen reported to ONP staff observing a Chinook salmon near Elkhorn Ranger Station (Rkm 40.2). In 2014, below the former Elwha dam site, Chinook salmon spawning activity was continuous and documented in all reaches (Table 7). This contrasted with 2012 and 2013, when at least four reaches had been surveyed without any redd observations. Over 38% (499 out of 1310) of all Chinook salmon redds observed in 2014 were found below the former Elwha dam site, making it the highest number and percentage of Chinook salmon redds below the dam since pre dam removal (Figure 5, Table 7). In 2015, visibility was again excellent and survey reaches from the previous year were used to conduct a river wide survey (Figure 6, Table 8). We counted 366 live and 387 dead Chinook adults of which 82% and 94% were located upstream of the former Elwha Dam site. A total of 937 Chinook salmon redds were located and identified, of which 77% (719 out of 937) were located in the middle Elwha (Figure 6, Table 8). The trend toward mainstem spawning preference continued, with 90% of the Chinook salmon redds located in the mainstem habitats, while only 10% were identified in Little River, Indian Creek, and Hughes Creek (Figure 6, Table 8). The 1.1 km reach immediately below Glines Canyon remained among the highest density reaches in the middle Elwha, though at a lower density than previous years (Figure 6, Table 8). We also made observations of pink salmon adults during the 2015 survey. A total of 80 live and 27 dead pink salmon adults were observed during the survey. Of these the majority (68%) were located above the former Elwha Dam site. Furthermore 77% of the pink salmon adults were observed in Little River, Indian and Hughes Creek. This was the first documented return of pink salmon adults to the middle river tributaries and was likely the first significant return of pink salmon above the former Elwha Dam site. 9 In 2016, despite the apparent reduction in total escapement, the spatial extent of Chinook salmon spawning was the greatest observed since survey efforts began in 2012 (Figure 7, Table 9). Over 75% of the total redds observed were located above Elwha Dam and the first significant numbers (58) of redds were observed above Glines Canyon (Figure 6). Chinook redds were also observed in lower Boulder Creek (8) and in Cat Creek (2) for the first time. A single Chinook salmon redd was observed in the upper Elwha River just below the confluence with Godkin Creek (Rkm 57.8) during upriver surveys (to Rkm 61.6) by ONP personnel (Figure 7). However, only one live Chinook was observed above Grand Canyon. We also did not observe a high density of redds immediately below Glines Canyon as in past years. This would suggest that passage conditions for Chinook salmon were improved in 2016 over 2015. In 2017, the spatial distribution of Chinook salmon redds was similar to that observed in 2016 (Figure 8, Table 10). The total number of redds located was 767, a 20% increase over 2016. A total of 523 (68%) redds were observed in the ME, and 192 (25%) redds were observed in the LE. In the UE we observed 52 (7%) total redds and of these, 92% were located in the former Mills Reservoir including the lower portions of Cat and Boulder Creeks. Only two redds were observed above the Grand Canyon of the Elwha, both in the vicinity of the confluence of Lost Creek, at Rkm 43.0. Surveyors also observed two live Chinook salmon, and possibly one more, in this reach. We also made observations of pink salmon adults during the 2017 season. Thirtyeight live pink salmon were reported during the surveys and all were in the middle Elwha. Ninety-two percent of the pink salmon were observed in Little River and Indian Creek. In 2018, the second highest number of Chinook redds were observed since the beginning of the project (Figure 9, Table 11). The peak count of 1,601 redds was over two times greater than the average count since 2012. Proportionally, the greatest number of redds were observed in the ME (57%), followed by the LE (30%), and the UE (13%). The 211 redds observed in the UE was the greatest observed since fish passage was reestablished in 2016. It should be noted that a total of 604 adult Chinook salmon were relocated from lower river hatcheries to a release point at the entrance of Glines Canyon. The distribution of Chinook redds in the UE was heavily skewed to areas below Goblins Gate and only 11 and 5 redds were observed in the Geyser Valley and above Grand Canyon, respectively. The most upstream redd was located above the confluence with Hayes River at Rkm 49.5. Surveyors also reported 5 sockeye salmon adults with confirmed spawning (3 redds) in the former Mills Reservoir. Due to a surplus of hatchery Chinook salmon, a total of 604 adults (491 males/113 females) were relocated to a release point below the former Glines Powerhouse (Rkm 19.2). Those fish were visibly marked using colored Spaghetti tags. Relocated fish were observed on subsequent spawning ground surveys both upstream and downstream of their release point. Of the 358 adult Chinook observed upstream of Glines Canyon, 44 (12%) were confirmed to have tags. . 10 In 2019, the highest total number of Chinook redds were observed since the beginning of the project (Figure 10, Table 12), slightly eclipsing the total for 2018. Proportionally, the greatest number of redds were observed in the ME (66%), followed by the LE (28%), and the UE (6%). The 104 redds observed in the UE was less than half what was observed in 2018. Similar to 2018, 614 adult Chinook were relocated from lower river hatcheries to a release point just above the ONP entrance. The distribution of Chinook redds in the UE was heavily skewed to the former Mills reservoir and its tributaries, Cat and Boulder Creeks. Only two Chinook adults and one redd were observed upstream of the Grand Canyon during snorkel surveys in early September. Due to a surplus of hatchery Chinook salmon, a total of 614 adults (204 males/410 females) were relocated to a release point at the Hot Springs Road washout (~Rkm 16). Those fish were visibly marked using colored Spaghetti tags. Some relocated fish were observed on subsequent spawning ground surveys both upstream and downstream of their release point, however there were not enough tag recoveries to determine the effect of that action. A small number of pink salmon redds (24) was observed, with the majority in Indian Creek and former Aldwell reservoir. One pair of pink salmon was observed above Glines Canyon, near the outlet of Rica Canyon, and a peak count of 26 pink salmon were observed in mainstem river snorkel surveys between Glines Canyon and Fisherman’s Bend. A total of 95 pink salmon were observed during the riverscape survey. This is the first year that pink salmon have been observed above the former Glines Canyon Dam site. Examination of redd density data over time suggests the density of adult spawning Chinook salmon in the area immediately upstream (i.e. < 5 km) from former Glines Canyon dam is increasing to levels seen in the Middle and Lower Elwha (Figure 11). Redd density levels above Rkm 30.0 are still low in comparison to the rest of the Elwha River. Examination of redd occupancy (presence of at least one redd in each tenth of a Rkm), excluding the canyon areas where no surveys have been conducted, reveals that 2018 had the highest level of occupancy seen since Chinook salmon redd surveys have been initiated in 2012 between and above the former dam locations (Figure 12). Discussion We conducted annual peak spawning ground surveys for Elwha River Chinook salmon during dam decommissioning (2012-2015) and the early stages of recolonization (2016-2019). These surveys were designed to provide information on the spatial distribution of Chinook salmon spawning nest locations as access to historic habitats was being restored. The surveys were not intended to enumerate the total number of Chinook salmon returning to the Elwha River. 11 In 2012, the proportion of Chinook salmon redds in the middle Elwha was evenly distributed between the mainstem and tributary habitat. The two major ME tributaries, Indian Creek and Little River, which enter on opposite sides of the Elwha River at Rkm 11.5, are the first clear water refugia above the former Elwha dam site and newly exposed former Aldwell Reservoir (Figure 3). Two other areas of concentrated Chinook salmon spawning activity were Rkm 16.5 to 18.0 (Rabbit Hole) and Rkm 9.8 to 11.4 (former Aldwell reservoir – Oxbow reach) (Figure 3). These patterns can largely be attributed to two factors. First, within the middle Elwha, Rkm 16.5 to 18.0 is one of several anastomosing (forested island) reaches, a habitat type where higher occurrence of Chinook salmon spawning activity has been documented in other studies due to local hydraulic conditions that promote upwelling (Vronskiy 1972, Vronskiy et al. 1991, Geist 2000). Second, mainstem Chinook salmon spawning was also concentrated in the former Aldwell Reservoir that had similar hydraulic characteristics as the Rabbit Hole reach, but was identified as less stable and more transient, similar to braided reaches (Beechie and Imaki 2014). However, it should also be noted that the Aldwell reach was immediately upstream of Elwha Dam and therefore the closest spawning habitat for recolonizing fish, which may select spawning sites according to distance upstream from the former barrier (Kiffney et al. 2008, Pess et al. 2012). The distribution of Chinook salmon redds was more extensive in 2013 (Figure 4), as redds were observed in each survey reach above the former Elwha dam site, and the density in each reach was similar or higher than observed in 2012 (Table 4 & 6). Unlike 2012, the vast majority of Chinook salmon redds were in the mainstem middle Elwha rather than the tributaries. This difference in distribution was hypothesized to occur for three primary reasons. First, turbidity levels in the mainstem Lower Elwha were lower at the time of the survey in 2013 than 2012 (Table 4). Second, connectivity between Little River, Indian Creek, and the mainstem was reduced in 2013 due to the development of mainstem gravel bars at the confluence of each tributary. Lastly and most importantly, between September 2012 and September 2013, there was a large increase in the amount of sediment released from the former Mills reservoir (Warrick et al. 2015), a process that increased the quantity and quality of Chinook salmon spawning habitat in the mainstem middle Elwha. In 2012, the mainstem middle Elwha did not markedly change in terms of sediment load and channel characteristics because the majority of sediment released by October of 2012 came from the former Elwha dam site (Warrick et al. 2015). Thus, the major changes in 2012 occurred below the former Elwha dam (East et al. 2015). However, between October of 2012 and September of 2013 large scale geomorphic changes occurred in the middle Elwha due to the substantial increase in sediment flux from the former Lake Mills delta, which was fully prograded to Glines Canyon and released ~ 8.9 million tons of sediment (Warrick et al. 2015). During that time period, the entire river aggraded due to an order of magnitude increase in 12 bedload material (Warrick et al. 2015). The bedload increase resulted in an increased riffle crest and channel thalweg elevation and bar formation. Substrate size in the middle Elwha also decreased 16 fold due to the influx of sand and gravel, and the density of mainstem channels increased (East et al. 2015). Prior to dam removal, the middle Elwha was characterized by cobble and boulder sized substrates greater than 64 mm (East et al. 2015), and so the reduction in substrate size may have provided a particularly large benefit to Chinook salmon spawning habitat quality. Much of this change occurred within the first 5 km downstream of the former Glines Canyon dam site (Figure 5), an area of high spawning density in 2013 and 2014 (Tables 6 and 7) (Figure 2). The 2016 Chinook return was one of the highest to the Elwha River in decades and we observed the second highest number of redds during the monitoring period. The spatial distribution of redds advanced upstream as the first significant number of redds was observed above Glines Canyon. In the fall of 2014, Glines Canyon Dam was in the final stages of removal during the bulk of the Chinook salmon migration, a process that was not complete until August 26th. The first Chinook salmon were observed in the former Mills Reservoir only 10 days after dam removal was completed and 3 redds were observed by ONP and LEKT employees. Chinook migration above Glines Canyon was inhibited in 2015 as a result of a rock fall shortly following dam removal in 2014. This blockage was subsequently blasted in the fall of 2015, but too late to allow upstream migration in the 2015 spawning year. Additional blasting was conducted in 2016 and those efforts appear to have been successful at improving passage conditions (at least for Chinook). While Chinook passage through Glines Canyon has been improved, it is uncertain if Chinook passage is optimal and if other species such as pink and chum salmon can pass through the canyon. This situation should be closely monitored as one of the Elwha project goals was to provide fish passage for all species of salmonids (DOI 1995). The 2016-2019 Chinook salmon spawner surveys were the most spatially extensive chinook survey efforts to date, coupled with the lower flows and lowest turbidity levels (Table 4). The rather continuous distribution of Chinook salmon redds observed in 2013-2019 (Figures 4-10) is likely due to the combination of relatively high abundance of spawners and an increase in the quantity and quality of spawning habitat. Visual observations made by spawning ground surveyors indicated that the mainstem spawning habitat in 2013-2019 was largely dominated by well sorted gravel deposits with minimal fine sediment. In contrast, many of the mainstem side-channels have persistent deposits of fine sediment on their channel beds (Pess et al. 2015; Peters et al. 2017). The post-dam removal Elwha River continues to be an active channel characterized by dynamic changes. Monitoring of surface and subsurface sediment at riffle crests downstream of Glines Canyon Dam to the mouth of the Elwha River has been conducted in concert with the Chinook spawning ground surveys. 13 Monitoring the spatial distribution of Chinook salmon has provided insights into the colonization of Chinook in the Elwha River following removal of two hydroelectric dams. Project partners have cooperated to extend survey coverage of the river in space and time. Immediately following dam removal, Chinook salmon volitionally recolonized habitats upstream of Elwha Dam, including Little River and Indian Creek. That upstream recolonization was mostly restricted by the Glines Canyon Dam until 2015, when supplemental fish passage work was conducted. In 2016 and 2017, the first significant numbers of Chinook ascended Glines Canyon and spawned in the upper watershed, primarily in the former Mills Reservoir area. While recolonization to the immediate areas upstream of Glines Canyon has initiated, the relatively few numbers of Chinook salmon documented to have reached watershed upstream of the Grand Canyon should be closely monitored (Figure 11). The Lower Elwha Klallam Tribe has proposed to relocate adult Chinook salmon into the upper watershed for a period of five years as a means of accelerating recolonization of habitats. The lack of Chinook to the headwaters may be the result of several factors. First, low densities of Chinook may result in redd selection occurring in the first suitable habitat encountered by migrating females. In this case, the newly exposed Mills Reservoir surface provided abundant, suitable spawning sites for early migrants. Burton et al. (2013) described this pattern for early Chinook migrants following installation of fish passage facilities on the Cedar River, Washington. Second, the Elwha Chinook population may have a high fidelity to the lower river where the WDFW hatchery (Rkm 8) is located. On the Chiwawa River, a higher proportion of hatchery female spring Chinook salmon spawned in the lower reaches of the river near acclimation release site, while greater numbers of natural origin Chinook utilized upstream habitats (Hughes and Murdoch 2017). A third possibility is that the Grand Canyon represents a formidable migration challenge, and the traits required to ascend it have been lost or truncated from the population. The Grand Canyon of the Elwha is the longest canyon and contains over 6.4 km of hydraulic drops (chutes, falls). The historic run of Chinook salmon that utilized habitats above the Grand Canyon was likely spring timed (Brannon and Hershberger 1984), possibly encountering Grand Canyon at a time of year when it was more easily ascended. This component of the population is currently at very low abundance. The existing hatchery population, which might also differ from the historic population at other traits required to migrate through steep canyons, may not be capable of recolonizing these habitats. Under this scenario, some level of natural selection and adaptive evolution may be required to achieve or accelerate colonization of upriver habitats or the rate of recolonization may be slow. Through a combination of the above reasons, the returning adults may be capable of ascending the difficult canyons, but not sufficiently motivated to make this effort. Regardless of the precise reason, or combination of reasons, Chinook have not populated the upper watershed in large numbers (although juvenile chinook have been observed in relatively low numbers throughout the areas surveyed above Grand Canyon). Actively transporting adults would place more fish 14 into suitable upriver habitats potentially accelerating the recolonization of habitats high in the watershed. Some believe this carries risks of undermining natural ecological and genetic processes that may be important for successful numerical and spatial expansion. Others think that the level of risk is low in areas where Chinook are currently in extremely low densities, and if progeny of adults relocated to the upper watershed are not genetically fit they will simply not survive. To date, there has been little evidence in these spawning ground surveys to suggest the revitalization of the spring Chinook component of the run. Chinook are observed in the stock composition surveys for the SONAR operation in early-June (Denton et al, 2019), which is consistent with previous work on the Elwha (Wunderlich et al, 1993). However, our survey efforts have not identified the separation in spawn timing that would be associated with a true spring chinook population. It may be that exposure to a natural selection regime in the upper river and reproductive isolation from hatchery-origin fish experiencing non-natural selection are important to the re-expression of the spring Chinook on the Elwha. Spring Chinook have declined dramatically coast-wide, and new research indicates that the phenotype for premature migration is genetically controlled in both steelhead and Chinook (Prince et al. 2017). Thompson et al. (2018) found that on both the Klamath and Rogue Rivers, the allele loss that controlled premature migration was rapid following dam construction. Extant mature (fall) Chinook populations on those rivers did not contain the premature migration allele at high enough frequency to prevent the complete loss the allele as a result of genetic drift. This genetic link may have significant implications to the recovery of this important life history. Acknowledgements This effort has been a multi-agency cooperative effort and would have not been possible without the assistance of many dedicated professionals over the years. The following individuals have contributed to the field surveys: Sam Brenkman, Pat Crain, Heidi Hugunin, Kathryn Sutton, James Starr, Anna Geffre, Josh Geffre, Brieuc Couillerot, and Phil Kennedy for ONP, John McMillan (Trout Unlimited), Todd Bennett and Martin Liermann (NOAA), Roger Peters (USFW), Randy Cooper, Joshua Weinheimer, Andrew Simmons, Lucas Young, Ryan Handeland, Steven Fredrickson, Matthew Choowong, Henry Kei, Dan Gorze, Leif Rinearson, Bethany Craig, Pete Topping, Clayton Kinsel, Pete Lisi and Chris O’Connell for WDFW, Mel Elofson, Ray Moses, Gabe Youngman, Sonny Sampson, Kim Williams, Wilson Wells, Allyce Miller and Keith Denton for LEKT, and Jeff Duda for USGS. Randall McCoy (LEKT) provided GIS support and maps produced in this report. Technical review was provided by Sam Brenkman, Pat Crain, Anna Geffre, Keith Denton and John Mahan and their comments greatly improved the quality of the report. 15 References Anderson, J., M. Mizell, M. Ackley, M. Mayer, M. 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Making the case for ecosystem restoration by dam removal in the Elwha River, Washington. Northwest Science, Volume 82:1-245. 19 Tables Table 1. Survey reaches, Rkm, and lead survey agency from 2012 to 2014. ONP = Olympic National Park, LEKT = Lower Elwha Klallam Tribe, and WDFW = Washington Department of Fish and Wildlife. Assistance in these surveys included other partners including the USGS, NOAA, and independent contractors. Survey Reach Above Glines powerhouse Glines Powerhouse to Top of Altaire Canyon Altaire Canyon to Altaire Bridge Altaire Bridge to Griff Creek Griff Creek to Rabbit Hole Hughes Creek Rabbit Hole to Fishermans Corner Fishermans Corner to Park Boundary Park Boundary to McDonald Bridge Gage McDonald Bridge Gage to A-Frame A-Frame to 101 Bridge Little River Indian Creek 101 Bridge to Boat Launch (Aldwell) Boat launch to Oxbow (Aldwell) Oxbow Reach (Aldwell) Oxbow Reach to Goosneck Gooseneck to Elwha Dam Dam outflow to hwy 112 bridge Hwy 112 bridge to weir Weir to new bridge New bridge to sisson's riffle Sisson's riffle to spruce hole Sisson's riffle to Hunt's Road Channel Right bank channel (LEKT hatchery) Hunt's Road channel Elwha bluff to mouth 20 Rkm start Rkm end Midpoint (Rkm) Length (km) 21.1 20.0 19.8 19.0 0.0 18.0 16.5 15.7 13.7 12.5 0.0 0.0 12.1 11.8 11.4 11.1 9.8 7.5 6.7 5.5 4.8 3.9 3.3 2.8 2.8 1.2 20.0 19.5 19.0 18.0 0.7 16.5 15.7 13.7 12.5 12.1 1.9 1.9 11.8 11.4 11.1 9.8 7.5 6.7 5.5 4.8 3.9 3.3 2.8 1.2 1.2 0.0 21.5 20.6 19.8 19.4 18.5 17.7 17.3 16.1 14.7 13.1 12.3 12.2 12.1 12.0 11.6 11.3 10.5 8.7 7.1 6.1 5.2 4.4 3.6 3.1 2.0 2.0 0.6 1.1 0.5 0.8 1.0 0.7 1.5 0.8 2.0 1.2 0.4 1.9 1.9 0.3 0.4 0.3 1.3 2.3 0.8 1.2 0.7 0.9 0.6 0.5 1.6 1.6 1.2 Lead survey team ONP ONP ONP ONP ONP ONP ONP ONP ONP ONP ONP LEKT LEKT LEKT LEKT LEKT LEKT LEKT WDFW WDFW WDFW WDFW WDFW WDFW LEKT LEKT LEKT Table 2. Revised survey reaches, Rkm, and lead survey agency adopted for 2015. ONP = Olympic National Park, LEKT = Lower Elwha Klallam Tribe, and WDFW = Washington Department of Fish and Wildlife. Assistance in these surveys included other partners including the USGS, NOAA, and independent contractors. Survey Reach Rkm start Above Glines powerhouse Glines Powerhouse to Top of Altaire Canyon Altaire Canyon to Altaire Bridge Altaire Bridge to Griff Creek Griff Creek to Rabbit Hole Hughes Creek Rabbit Hole to Fishermans Corner Fishermans Corner to Park Boundary Park Boundary to McDonald Bridge Gage McDonald Bridge Gage to A-Frame A-Frame to 101 Bridge Little River Indian Creek Aldwell South (101 Bridge to Gooseneck) Aldwell North (Gooseneck to Elwha Dam) Dam outflow to Hwy 112 bridge Hwy 112 bridge to County bridge County bridge to Spruce Hole East Channel (LEKT Hatchery) Hunt's Road channel Elwha bluff to mouth 21.1 20.0 19.8 19.0 0.0 18.0 16.5 15.7 13.7 12.5 0.0 0.0 12.1 9.8 7.5 6.7 4.8 2.8 2.8 1.2 21 Rkm end Midpoint (Rkm) Length (km) 20.0 19.5 19.0 18.0 0.7 16.5 15.7 13.7 12.5 12.1 1.9 1.9 9.8 7.5 6.7 5.8 2.8 1.2 1.2 0.0 21.5 20.6 19.8 19.4 18.5 17.7 17.3 16.1 14.7 13.1 12.3 12.2 12.1 11.0 8.7 7.1 6.1 3.8 2.0 2.0 0.6 1.1 0.5 0.8 1.0 0.7 1.5 0.8 2.0 1.2 0.4 1.9 1.9 2.3 2.3 0.8 1.9 2.0 1.6 1.6 1.2 Lead survey team ONP ONP ONP ONP ONP ONP ONP ONP ONP ONP ONP LEKT LEKT LEKT LEKT WDFW WDFW WDFW LEKT LEKT LEKT Table 3. Revised survey reaches, Rkm, and lead survey agency since 2016. ONP = Olympic National Park, LEKT = Lower Elwha Klallam Tribe, and WDFW = Washington Department of Fish and Wildlife. Assistance in these surveys included other partners including the USGS, NOAA, and independent contractors. Survey Reach Rkm start Rkm end Midpoint (Rkm) Length (km) Lead survey team Upper Elwha Upper Watershed Rica Canyon to Dodger Point (Geyser Valley) Glines Powerhouse to Rica Canyon (Mills) 31.8 25.7 21.1 56.0 31.8 25.7 43.8 28.8 23.4 24.2 6.1 4.6 ALL ALL ALL Middle Elwha Glines Powerhouse to Top of Altaire Canyon Top of Altaire Canyon to Elwha Ranger St. Elwha Ranger Station to Rabbit Hole Rabbit Hole (Hughes) to Fishermans Corner Fishermans Corner to Park Boundary Park Boundary to McDonald Bridge Gage McDonald Gage to 101 Bridge Little River Indian Creek Aldwell South (101 Bridge to Gooseneck) Aldwell North (Gooseneck to Elwha Dam) 21.1 20.0 19.0 18.0 16.5 15.7 13.7 0.0 0.0 12.3 9.8 20.0 19.0 18.0 16.5 15.7 13.7 12.1 1.9 1.9 9.8 7.9 20.6 19.5 18.5 17.3 16.1 14.7 12.9 12.2 12.1 11.0 8.8 1.1 1.0 1.0 1.5 0.8 2.0 1.6 1.9 1.9 2.5 1.9 ONP ONP ONP ONP WDFW WDFW WDFW LEKT LEKT LEKT LEKT Lower River Dam outflow to Hwy 112 bridge Hwy 112 bridge to County bridge County bridge to Spruce Hole East Channel (LEKT Hatchery) Hunt's Road Channel 7.9 6.7 4.8 2.8 2.8 6.7 4.8 2.8 0.0 1.2 7.3 6.1 3.8 1.4 2.0 1.2 1.9 2.0 2.8 1.6 WDFW WDFW WDFW LEKT LEKT 22 Table 4. Discharge, turbidity levels and suspended sediment concentration during Chinook salmon spawning ground surveys conducted in the Elwha River, 2012-2016. Water quality measurements were measured at monitoring station 12046200, while discharge measurements were at station 12045500 (Curran et al. 2014). Year Date Flow (cms) Median SSC (mg/L) 11.9 (±2.9) Turbidity level (FNU) (±S.D.) 72 (±30) 2012 Sept 12-17 2013 57 Visibility good above Elwha Dam, limited surveys conducted below due to high turbidity Sept 17 11.1 (±0.7) 45 (±2.0) 77 Visibility good above Elwha Dam, fair below Elwha Dam due to high turbidity 2014 Sept 17 7.0 (±0.2) 5 (±2.0) 55 Visibility excellent in all reaches 2015 Sept 23-24 9.9 (±0.2) 0.8 (±0.4) - Visibility excellent in all reaches 2016 Sept 19-23 8.5 (+0.2) 5.0 (+2.0) - Visibility generally good w/exception of construction impacts in lower river 2017 Sept 18-25 11.3 (+0.3) 2.3 (+0.3) - 2018 Sept 12-28 11.3 (+1.4) (5.0 +3.0) - 2019 Sept 26 11.3 (+1.8) (2.1+0.1) - 23 Comments Visibility excellent in all reaches Two flow spikes during survey period. Flows quickly receded Visibility excellent in all reaches Table 5. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2012. NS = Not Surveyed. Survey Reach Rkm midpoint 21.5 Redds Redds/km Male Female Unknown Dead Jacks NS NS NS NS NS NS NS Middle Elwha Glines Powerhouse Altaire Canyon Altaire Bridge Griff Creek Hughes Creek Rabbit Hole Fishermans Corner Park Boundary McDonald Bridge A-Frame Little River Indian Creek 101 Bridge Boat launch Oxbow Reach Oxbow Reach2 Gooseneck ME Subtotal 20.6 19.8 19.4 18.5 17.7 17.3 16.1 14.7 13.1 12.3 12.2 12.1 12.0 11.6 11.3 10.5 8.7 6 NS 0 8 NS 33 0 0 2 0 40 58 10 1 30 15 0 203 (93.5%) 5.5 NS 0.0 8.0 NS 22.0 0.0 0.0 1.7 0.0 21.1 30.5 33.3 2.5 100.0 11.5 0.0 11.0 0 NS 2 0 NS 7 0 0 0 0 28 29 0 0 0 0 0 66 0 NS 3 0 NS 1 0 0 0 0 16 28 0 0 0 0 0 48 23 NS 3 0 NS 102 0 0 0 0 0 0 6 3 31 5 0 173 1 NS 1 1 NS 18 0 0 1 0 18 27 0 2 5 8 0 82 1 NS 1 0 NS 1 0 0 0 0 8 14 0 0 0 0 0 25 Lower Elwha4 Dam outflow Hwy 112 bridge Weir New bridge Sisson's riffle1 Sisson's riffle2 Right bank channel Hunt's Road channel Elwha bluff to mouth LE Subtotal 7.1 6.1 5.2 4.4 3.6 3.1 2.0 2.0 0.6 0 0 4 4 4 2 0 0 0 14 (6.5%) 0.0 0.0 5.7 4.4 6.7 4.0 0.0 0.0 0.0 1.5 0 0 0 0 0 0 NS NS NS 0 0 0 0 0 0 0 NS NS NS 0 0 0 0 0 0 0 NS NS NS 0 0 0 2 0 0 0 NS NS NS 2 0 0 0 0 0 0 NS NS NS 0 66 48 173 84 25 Above Glines TOTAL 217 4 Observations of redds in the lower Elwha below Rkm 5.2 were limited or not possible during 2012 surveys because of limited visibility associated with dam removal activities. 24 Table 6. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2013. NS = Not Surveyed. Survey Reach Rkm midpoint 21.5 Redds Redds/km Male Female Unknown Dead Jacks NS NS NS NS NS NS NS Middle Elwha Glines Powerhouse Altaire Canyon Altaire Bridge Griff Creek Hughes Creek Rabbit Hole Fishermans Corner Park Boundary McDonald Bridge A-Frame Little River Indian Creek 101 Bridge Boat launch Oxbow Reach Oxbow Reach2 Gooseneck ME Subtotal 20.6 19.8 19.4 18.5 17.7 17.3 16.1 14.7 13.1 12.3 12.2 12.1 12.0 11.6 11.3 10.5 8.7 162 11 42 73 8 59 13 45 8 16 23 58 68 147.3 22.0 52.5 73.0 11.4 39.3 16.3 22.5 6.7 40.0 12.1 30.5 29.6 132 0 11 30 6 8 7 4 1 0 23 43 19 103 2 14 18 7 19 3 0 3 0 12 19 19 60 0 25 22 0 14 23 108 6 13 0 0 24 77 10 30 51 39 32 33 47 35 6 9 64 20 2 0 0 1 1 0 0 4 0 0 0 5 0 16 602 (78.6%) 7.0 32.7 12 296 6 225 20 315 7 460 0 13 Lower Elwha5 Dam outflow Hwy 112 bridge Weir New bridge Sisson's riffle1 Right bank channel Hunt's Road channel Elwha bluff to mouth LE Subtotal 7.1 6.1 5.2 4.4 3.6 2.0 2.0 0.6 51 100 9 3 0 0 NS 0 163 (21.4%) 63.8 83.3 12.9 3.3 0.0 0.0 NS 0.0 19.0 0 0 0 0 0 0 NS 0 0 0 0 0 0 0 0 NS 0 0 81 251 13 0 13 23 NS 0 381 16 25 20 0 0 1 NS 0 62 0 0 0 0 0 0 NS 0 0 296 225 696 522 13 Above Glines TOTAL 765 5 Observations of redds in the lower Elwha below Rkm 5.2 were limited or not possible during 2013 surveys because of limited visibility associated with dam removal activities. 25 Table 7. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2014. Survey Reach Rkm midpoint 21.5 Redds Redds/km Male Female Unknown Dead Jacks 1 - 0 0 4 0 0 Middle Elwha Glines Powerhouse Altaire Canyon Altaire Bridge Griff Creek Hughes Creek Rabbit Hole Fishermans Corner Park Boundary McDonald Bridge A-Frame Little River Indian Creek 101 Bridge Boat launch Oxbow Reach Oxbow Reach2 Gooseneck ME Subtotal 20.6 19.8 19.4 18.5 17.7 17.3 16.1 14.7 13.1 12.3 12.2 12.1 12.0 11.6 11.3 10.5 8.7 241 29 63 82 12 69 55 82 17 35 1 26 57 219.1 58.0 78.8 82.0 17.1 46.0 68.8 41.0 14.2 87.5 0.5 13.7 24.8 0 0 18 9 3 43 25 36 2 3 0 0 0 0 0 22 12 5 29 7 22 1 2 0 0 0 257 23 29 24 0 14 58 148 24 73 0 89 62 57 19 21 49 3 56 49 49 17 12 0 0 26 0 0 0 0 0 0 0 0 0 0 0 0 0 42 811 (61.9%) 18.3 44.1 0 139 0 100 61 862 40 398 0 0 Lower Elwha Dam outflow Hwy 112 bridge Weir New bridge Sisson's riffle1 Right bank channel Hunt's Road channel Elwha bluff to mouth LE Subtotal 7.1 6.1 5.2 4.4 3.6 2.0 2.0 0.6 50 125 25 14 83 154 47 1 499 (38.1%) 62.5 104.2 35.7 15.6 138.3 96.3 29.4 0.8 27.1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 65 33 36 87 0 14 0 245 NA NA NA NA NA NA NA NA 0 0 0 0 0 0 0 0 0 0 139 100 1111 398 0 Above Glines TOTAL 1310 26 Table 8. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2015. Survey Reach Above Glines Middle Elwha Glines Power. Altaire Canyon Altaire Bridge Griff Creek Hughes Creek Rabbit Hole Fisherman’s C. ONP Boundary McDonald Br. A-Frame Little River Indian Creek Aldwell South Aldwell North ME Subtotal Lower Elwha Dam outflow Hwy 112 Bridge County Bridge Sisson's Riffle East Channel Hunt Rd. Chan. Elwha Bluff LE Subtotal Rkm midpoint 21.5 Redds Redds/km Live Dead Chinook Chinook 0 0 0 0 20.6 19.8 19.4 18.5 17.7 17.3 16.1 14.7 13.1 12.8 12.2 12.1 11.6 8.7 100 35 24 34 3 50 84 77 31 37 51 18 93 82 719 (76.7%) 90.9 70.0 30.0 34.0 4.3 33.3 105.0 38.5 25.8 92.5 26.8 9.5 40.4 35.6 45.5 68 12 14 13 1 37 8 23 5 6 25 24 29 34 299 7.1 6.1 8 66 10.0 55.0 4.4 3.6 2.0 2.0 0.6 31 18 40 55 0 218 (23.3%) 16.3 9.0 25.0 34.4 0.0 21.4 TOTAL 937 27 Jacks 0 Live Pinks 0 Dead Pinks 0 14 2 4 5 4 6 32 12 2 28 32 5 132 87 365 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 16 0 0 2 3 0 17 5 1 5 49 0 0 0 0 13 0 1 0 0 1 3 2 1 3 24 0 5 2 2 0 0 0 19 0 0 16 5 18 26 0 67 2 1 9 6 0 22 0 0 0 0 0 0 3 0 3 6 0 31 1 0 2 0 0 3 366 387 0 80 27 Table 9. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2016. Survey Reach Upper Elwha Upper Watershed Geyser Valley Former Mills Reservoir UE Subtotal Rkm midpoint Redds Redds/km Live Chinook Dead Chinook Jacks 43.8 28.8 23.4 1 10 47 0.0 1.6 10.4 0 4 29 0 0 6 0 0 2 58 (9.5%) 1.5 33 6 2 36 15 0 24 31 29 0 0 0 0 0 28 0 24 14 13 186 0 14 12 20 74 5 0 0 0 0 0 0 0 0 1 0 6 17 8 6 2 25 3 0 11 0 0 0 0 0 0 244 91 8 Middle Elwha Glines Power. Altaire Bridge Griff Creek Rabbit Hole Fisherman’s C. ONP Boundary McDonald Br. Little River Indian Creek Aldwell South Aldwell North ME Subtotal 20.6 19.5 18.5 17.3 16.1 14.7 12.9 12.2 12.1 11.0 8.8 36 19 27 30 78 42 15 1 28 48 86 410 (66.7%) 32.7 19.0 4.0 20.0 97.5 21.0 9.4 0.5 14.7 20.9 45.3 24.1 Lower Elwha Dam outflow Hwy 112 Bridge County Bridge East Channel Hunt Rd. Chan. LE Subtotal 7.3 6.1 3.8 1.4 2.0 16 74 23 30 3 146 (23.8%) 13.3 38.9 11.5 10.7 1.9 15.4 TOTAL 614 28 Table 10. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2017. Note that live and dead counts were accidentally aggregated among some reaches in the middle Elwha. Survey Reach Upper Elwha Upper Watershed Geyser Valley Former Mills Reservoir UE Subtotal Rkm midpoint Redds Redds/km Live Chinook Dead Chinook Jacks 43.8 28.8 23.4 2 2 48 0.07 0.33 10.4 2 3 87 0 1 10 0 0 0 92 11 0 61 28 100 34 127 22 26 68 100 63 545 0 13 47 27 171 115 20 44 32 191 4 13 37 828 219 52 (6.8%) Middle Elwha Glines Power. Altaire Bridge Griff Creek Rabbit Hole Fisherman’s C. ONP Boundary McDonald Br. Little River Indian Creek Aldwell South Aldwell North ME Subtotal 20.6 19.5 18.5 17.3 16.1 14.7 12.9 12.2 12.1 11.0 8.8 79 52 8 50 58 32 6 9 35 128 66 523 (68.2) 71.8 52.0 8.0 33.3 72.5 16.0 3.7 4.7 18.4 55.6 34.7 Lower Elwha Elwha Dam Hwy 112 Bridge County Bridge East Channel Hunt Rd. Chan. LE Subtotal 7.3 6.1 3.8 1.4 2.0 7 77 37 31 40 192 (25.0%) 767 5.8 40.5 18.5 19.8 14.3 TOTAL 29 4 1 5 5 Table 11. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2018. Survey Reach Upper Elwha Upper Watershed Long Creek Geyser Valley Cat Creek Boulder Creek Mills UE Subtotal Rkm midpoint Redds Redds/km Live Chinook Dead Chinook Jacks 43.8 5 0 11 25 21 149 211 (13.2%) 0.2 0.0 1.8 25.0 42.0 32.4 6 0 36 26 91 129 288 0 0 3 10 25 32 70 0 0 0 0 1 1 2 28.8 23.4 Middle Elwha Glines Power. Altaire Bridge Griff Creek Rabbit Hole (Hughes) Fisherman’s C. ONP Boundary McDonald Br. Little River Indian Creek Aldwell South Aldwell North ME Subtotal 20.6 19.5 18.5 17.3 16.1 14.7 12.9 12.2 12.1 11.0 8.8 71 28 42 132 49 33 43 63 144 206 98 909 (56.8%) 64.5 28.0 42.0 88.0 61.2 16.5 26.9 33.2 75.8 89.6 51.6 91 112 38 133 18 26 49 108 97 149 62 883 26 45 55 65 37 18 15 52 58 115 71 557 0 0 0 0 0 1 0 0 0 0 0 1 Lower Elwha Elwha Dam Hwy 112 Bridge County Bridge East Channel Hunt Rd. Chan. LE Subtotal 7.3 6.1 3.8 1.4 2.0 84 186 87 82 42 481 (30.0%) 1,601 70.0 97.9 43.5 29.3 26.3 151 182 26 359 40 104 29 17 0 0 0 1,530 800 3 TOTAL 30 Table 12. Number of redds, redds/kilometer and observation of live, dead and jack Chinook salmon on the Elwha River, 2019. Survey Reach Upper Elwha Upper Watershed Long Creek6 Geyser Valley Cat Creek Boulder Creek Mills UE Subtotal Rkm midpoint Redds Redds/km Live Chinook Dead Chinook Jacks 43.8 1 0.04 2 0 0 28.8 5 9 22 67 104 (6.2%) 0.8 6.0 44.0 14.5 8 3 8 73 94 7 8 39 61 115 0 0 0 0 0 23.4 Middle Elwha Glines Power. Altaire Bridge Griff Creek Rabbit Hole (Hughes)7 Fisherman’s ONP Boundary McDonald Br. Little River Indian Creek Aldwell South Aldwell North ME Subtotal 20.6 19.5 18.5 17.3 16.1 14.7 12.9 12.2 12.1 11.0 8.8 46 34 34 133 67 42 14 124 215 259 131 1099 (65.7%) 41.8 34.0 34.0 88.7 83.7 21.0 8.7 65.3 113.2 112.6 68.9 51 23 176 17 29 6 30 48 33 8 421 164 16 125 0 0 0 91 159 60 69 684 0 0 0 0 0 0 0 0 0 0 0 Lower Elwha Elwha Dam Hwy 112 Bridge County Bridge8 East Mainstem Hunt Rd. Chan. LE Subtotal 7.3 6.1 3.8 1.4 2.0 36 248 120 42 24 470 (28.1%) 1673 45.0 145.9 66.7 18.3 16.0 400 11 11 422 398 45 12 455 0 0 0 937 1,254 0 TOTAL 6 Long Creek was not surveyed in 2019 Live/Dead Counts aggregated for Hughes/Griff survey reaches 8 Live/Dead Counts aggregated for Dam/112 Bridge/County Bridge reaches 7 31 Figures Figure 1. The Elwha River watershed. Note that canyon areas depicted in white are not surveyed. 32 Figure 2. Total number of Chinook salmon redds between former Elwha dam and Glines Canyon dam 2012 to 2019. Black bars indicate the number of chinook redds below former Elwha dam. Grey bars indicate the number of Chinook redds between former Elwha dam and former Glines Canyon dam, and red bar indicates the number of redds above former Glines Canyon dam. 2,000 Chinook salmon redds 1,800 1,600 Redds above all dams Redds between dams Redds below dams 1,400 1,200 1,000 800 600 400 200 0 2012 2013 2014 2015 2016 Year 33 2017 2018 2019 Figures 3. Distribution of Chinook redds in the Elwha River 2012. 34 Figures 4. Distribution of Chinook redds in the Elwha River 2013. 35 Figures 5. Distribution of Chinook redds in the Elwha River 2014. 36 Figures 6. Distribution of Chinook redds in the Elwha River 2015. 37 Figures 7. Distribution of Chinook redds in the Elwha River 2016. 38 Figures 8. Distribution of Chinook redds in the Elwha River 2017. 39 Figures 9. Distribution of Chinook redds in the Elwha River 2018. 40 Figure 10. Distribution of Chinook redds in the Elwha River 2019. 41 Figure 11. Density of Chinook salmon redds from river kilometer (RKM) 0.0 to 30.0 on the Elwha River 2012 to 2019. Open circles are the mean across years while solid lines with perpendicular bars are the standard errors. Chinook salmon redds/100m 45.00 Former Glines Canyon Dam Former Elwha Dam 40.00 35.00 30.00 25.00 20.00 15.00 10.00 5.00 0.00 0 2 4 6 8 10 12 14 16 Rkm 42 18 20 22 24 26 28 30 Figure 12. Chinook salmon redd occupancy by year and river section. Chinook salmon redd location was identified to the nearest tenth of a Rkm surveyed from 2012 to 2019 to estimate the total percent linear occupancy for the Elwha River. Elwha River Chinook salmon redd occupancy by year & river section Percent occupancy 100% 75% Below Between Above 50% 25% 0% 2012 2013 2014 2015 2016 Year 43 2017 2018 2019 Estimate Figure 13. Historical escapement of Chinook salmon to the Elwha River 1984-2019 (from Denton et al 2020). Estimates were made by river surveys from 1984-2010. Estimates from 2010-2019 were made using SONAR cameras. The 2019 estimate is currently not available. 10,000 9,000 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0 Redd based SONAR Year 44