Garcia and Associates One Saunders Avenue San Anselmo, CA Phone: (415) Fax: (415)

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1 Garcia and Associates One Saunders Avenue San Anselmo, CA Phone: 415) Fax: 415) To: From: Gregory Andrew, Fishery Program Manager Marin Municipal Water District Rob Aramayo Date: 26 Feb 2013 RE: Walker Creek Salmon Monitoring Program: 2012 Juvenile Survey & 2012/2013 Spawner Survey Report BACKGROUND In the early 1900s, coho salmon Oncorhynchus kisutch) were abundant in Walker Creek, a tributary to Tomales Bay in western Marin County, CA; however, they appear to have been extirpated by 1948 MMWD unpublished data). Severe erosion and landform changes associated with dominant land-use practices during the past 100 years have resulted in a dramatic decline of anadromous fish throughout the region Hammack 2005). For example, the creation of Soulajule Reservoir by a private landholder in the 1960s blocked all anadromous fish migration to the upper reaches of Arroyo Sausal, thereby eliminating steelhead Oncorhynchus mykiss) and coho salmon from a significant portion of their historic range in the watershed. Several efforts to reintroduce coho salmon into Walker Creek began in the mid-1970s. California Department of Fish and Wildlife CDFW) stocked 47,079 coho yearlings between 1977 and 1980 and an additional 22,000 coho fingerlings in In 1979, Soulajule Reservoir was expanded by Marin Municipal Water District MMWD) to increase municipal water storage. This reservoir expansion established new minimum flow requirements for Walker Creek Table 1) Table 1. Minimum flow releases for Walker Creek in cubic feet per second cfs) Season Normal Years Dry Years Critical Dry Years Winter 20 cfs 10 cfs 0.5 cfs Summer 5 cfs 2 cfs 0.5 cfs In an attempt to re-establish a viable population of coho salmon, the CDFW began a multiple-year 1

2 effort in 2003 of planting coho salmon into Walker Creek. Since the winter of 2003/2004, a total of 364 adult coho salmon, 3,400 coho smolts, and 29,000 coho fingerlings have been released into Walker Creek Table 2). Planting of these fish is the latest in a long-standing series of efforts to reestablish coho salmon in Walker Creek. MMWD has partnered with CDFW in these efforts by conducting monitoring surveys to help evaluate the success of the program. This effort to reintroduce and improve habitat conditions for coho salmon began after no coho were collected during CDFW electrofishing surveys in 1993, and no coho were observed during a snorkel survey conducted by the National Marine Fisheries Service NMFS) in CDFW began a coho hatchery-rearing program in Juvenile coho salmon were collected from nearby Olema Creek, in the Lagunitas Creek watershed, and raised at either the Warm Springs Hatchery or the Bodega Marine Laboratory. These fish of Olema Creek origin have been the source of all Walker Creek coho salmon releases since the winter of 2003/2004 as detailed in Table 1 below pers. comm. M. Kittel, CDFG). Table 2. Walker Creek Coho Salmon Releases since 2003 Season Winter 2003/2004 Winter 2004/2005 Winter 2005/2006 June 2007 January 2008 November 2008 December 2008 December 2010 November 2011 November 2012 Source: California Department of Fish & Wildlife Coho Salmon Releases 80 adults 87 adults 40 adults 3,400 smolts 57 adults 500 fingerlings 100 adults 6,500 fingerlings 12,000 fingerlings 10,000 fingerlings A grant received from CDFW through the Fisheries Restoration Grant Program has allowed MMWD to expand coho monitoring efforts in Walker Creek to determine the success of the stocking effort. Garcia and Associates GANDA) contracted with MMWD to conduct coho salmon surveys during 2011 and 2012 in order to determine: If adult coho salmon spawn in Walker Creek; If a population of juvenile coho salmon is present in Walker Creek, and if these juveniles are offspring of the planted coho or part of a naturally occurring population; and If there are adult coho salmon returning to Walker Creek and if these adults are offspring of the planted coho or part of a naturally occurring population A secondary benefit from the monitoring program will be the acquisition of additional information regarding the steelhead population in Walker Creek and perhaps incidental information on other potential salmonids, like chinook salmon Oncorhynchus tshawytscha). This memorandum reports the results of the juvenile coho surveys conducted in September and October 2012 and the adult coho salmon spawner surveys conducted by MMWD and GANDA between November 2012 and January

3 STUDY AREA The study area for the Walker Creek Salmon Monitoring Program Figure 1) included the upper portion of the Walker Creek watershed accessible to salmon, primarily between Soulajule Reservoir and the McLaughlin Ranch downstream of the Walker Creek Ranch. Surveyed tributaries included Arroyo Sausal, Salmon Creek, Verde Canyon Creek, and Frink Canyon Creek. The extent of the survey areas for the different study elements was largely determined by landowner access. The study area for adult spawner surveys was divided into four study reaches Figure 2): Reach A included Arroyo Sausal from Soulajule Reservoir downstream to the Salmon Creek confluence note that approximately 300 meters of this reach immediately upstream of the confluence with Salmon Creek was consistently too deep and brush-choked to survey); Reach B included Walker Creek from the confluence with Salmon Creek downstream to Marshall-Petaluma Road, as well as approximately one mile of Salmon Creek immediately upstream of the Walker Creek confluence; Reach C included Walker Creek from Marshall-Petaluma Road downstream to the lower extent of the Walker Creek Ranch property owned by the Marin County Office of Education); Reach D included Walker Creek from the bottom of Walker Creek Ranch downstream to the bottom of the McLaughlin Ranch property boundary, upstream of the confluence with Chileno Creek. METHODS Juvenile Coho Snorkel Surveys During snorkel surveys, two GANDA biologists walked the entire 8-mile survey area Sections A, B, C, and D described above) and swam through and visually snorkel surveyed, looking for all fish in each habitat unit 1.5 feet deep or deeper, working in the upstream direction. All fish observed were identified and enumerated, and the pool location for coho) was recorded using a handheld GPS unit. Snorkel surveys were conducted from September 5 through October 19, Juvenile Coho Electrofishing Surveys Qualitative one-pass electrofishing surveys were also conducted to supplement snorkel survey data and allow collection of tissue samples from juvenile coho salmon for genetic analysis. Three pools in Reach C were electrofished on October 30, During each survey, a team of biologists 1 backpack electrofisher and 2 netters) comprised of MMWD staff fished the selected reach from the downstream to upstream end, capturing as many fish as possible during a single pass. All collected fish were identified to species; coho salmon and steelhead specimens were to be enumerated and measured to the nearest mm fork length FL). Fin clips were also to be collected from all coho specimens for genetic analysis. All fin clips were to be sent to the NOAA genetics lab in Santa Cruz for analysis. [However, no coho juveniles were found during this effort, and samples were therefore not collected nor sent.] 3

4 Adult Spawner Surveys Spawner surveys were conducted approximately bi-weekly from late November 2012 through late January During each survey, teams of biologists walked upstream through each reach looking for adult fish and any evidence of spawning. Teams were comprised of a combination of MMWD and GANDA staff. Crews recorded all observations of live fish, carcasses, and redds. Each recorded observation was assigned a record number describing the type of observation, stream reach, and date of survey. All live fish were identified to species and the certainty of each identification was recorded as either: 1) sure, 2) maybe one species or another, or 3) unknown. Fork length and sex of any carcasses were also recorded with the certainty of gender identifications ranked as above), where possible. Visual estimates of the fork length of live fish were made when possible. Any tags, clips, brands, or other identifying marks were also noted. If an individual fish was observed on or near a redd, the redd number was recorded on the fish data sheet see Appendices B and C below). Carcasses were described as above, and assigned a carcass tag coho carcasses only). Tissue samples were to be collected from the dorsal fin and operculum of each coho carcass and sent to the genetics lab at the National Oceanic and Atmospheric Administration NOAA) National Marine Fisheries Service Southwest Fisheries Science Center in Santa Cruz for genetic analysis. For each newly encountered carcass, the tail was to be severed at the caudal peduncle in order to designate that carcass as having been previously documented i.e., so that it could not be mistaken as a new carcass during subsequent surveys). Carcass locations were also recorded using a GPS and marked on the reach map. All observed redds were visually identified to species when possible. For each redd, the dimensions of the pit length, width, and depth) and the tail spill length and two widths) were to be recorded. During each survey, only new redds not observed in any previous survey were documented. Redd locations were flagged with the date, redd number, species coho or steelhead), redd dimensions, and redd position e.g., mid-channel, left or right bank) marked on the flagging. Redd locations were also recorded using GPS and marked on the reach maps. If a live fish was observed on or near a redd, the redd record number was noted on the fish data sheet. Any redds with fish present on them were noted and left to be measured at a later date so as not to disturb spawning activities. RESULTS 2012 Juvenile Snorkel Surveys Juvenile coho surveys were conducted in Sections A through D Figure 2) between September 5 and October 19, No coho were positively identified during the surveys. Steelhead and California roach Hesperoleucus symmetricus) were the most abundant species observed. Sculpin Cottus sp.) and three-spine stickleback Gasterosteus aculeatus) were also observed. A summary table of all fish observed is presented in Table 3. 4

5 Table 3. Summary of Fish Observed during Juvenile Coho Snorkel Surveys, September and October Location Habitats Coho Steelhead Un. Sal Roach Stickleback Sculpin Total Frink Canyon 0 dry) Verde Canyon Walker Creek Salmon Creek Arroyo Sausal Total Fish Visibility in mainstem Walker Creek was between 1 and 2 meters during most of the 2012 juvenile surveys. Water clarity in Salmon Creek was excellent, while visibility in Verde Canyon Creek was quickly muddied and the visibility in Arroyo Sausal was always poor. Tributaries generally consisted of isolated pools connected by sub-surface flow or small surface trickles. Most pools appeared to provide suitable refugia for fish, with relatively cool water temperatures and adequate cover. Walker Creek Mainstem During the surveys 158 habitat features were visually observed in the mainstem of Walker Creek. No juvenile coho salmon were observed in Steelhead 1,733) and California roach 783) were by far the most abundant species observed. There was also one salmonid observed in the mainstem which could not be positively identified. Also observed were 56 three-spine stickleback and 11 sculpin Table 3). Frink Canyon Creek Frink Canyon Creek was surveyed from its confluence with Walker Creek to approximately onequarter mile upstream. This reach was dry in 2012; there were no habitat features 1.5 feet deep or greater. Dense vegetation restricted access to the channel upstream of this point. No coho salmon were observed Table 3). Verde Canyon Creek Verde Canyon Creek was surveyed from its confluence with Walker Creek to just above the Marshall-Petaluma Road crossing approximately 0.25 stream miles). The culvert at the Marshall- Petaluma Road crossing appears to serve as a barrier to upstream fish migration under most flow conditions. No flow was present through the culvert during our survey. We observed one steelhead, 264 California roach, and 105 three-spine stickleback in the four pools in the reach below the Marshall- Petaluma Road crossing. No coho salmon were observed in Verde Canyon Creek. Salmon Creek 5

6 In Salmon Creek, 26 habitat features were surveyed from its confluence with Walker Creek to the upstream extent of the study area approximately 1 stream mile). This larger tributary had more frequent and larger-sized pools, with higher fish abundances than other tributaries. California roach 440) were the most abundant fish species present Table 3). Steelhead were the second-most abundant fish species observed 124). Additionally, 42 three-spine stickleback and 45 sculpin were also observed. No juvenile coho salmon were observed in Salmon Creek in Arroyo Sausal Arroyo Sausal was surveyed from its confluence with Salmon Creek to the dam. The lower area below between the confluence and the bridge was surveyed as one unit. Between the bridge and the dam, 9 additional units were surveyed. The visibility was poor in this reach; no fish were observed Table 3) Juvenile Electrofishing Surveys Qualitative one-pass electrofishing conducted in 3 pool features in Section C on October 30, 2012, produced 45 steelhead and 36 sculpin. No coho, California roach, or three-spine stickleback were captured during the electrofishing effort. The area surveyed is shown in Figure 2. The juvenile steelhead ranged from mm fork length. A summary of 2012 electrofishing data is provided in Appendix A. The sample area was selected randomly since no coho had been observed during the snorkel surveys and so there was no specific area to focus electrofishing sampling. Winter 2012/2013 Spawner Surveys GANDA and MMWD staff completed five adult surveys during the 2012/2013 spawning season November 20, December 10, and January 3, 15 and 31). Two adult coho, one live and one carcass, and one coho redd were found during the 2012/2013 spawner surveys. Five live adult steelhead and two unidentified live salmonids, and 18 steelhead redds were observed during our surveys. Fish observations from 2012/2013 spawner surveys are summarized in Appendix B. Redd observations are summarized in Appendix C. The locations of redd observations within each survey reach are also illustrated in Figure 3. Reach A Soulajule Reservoir downstream to Salmon Creek confluence) No live adult coho salmon or steelhead, carcasses, or redds were observed in Reach A. However, a watershed resident described seeing large salmonids below the Soulajule Reservoir dam during a high flow event in December These may have been coho although the observation could not be confirmed Reach B Salmon Creek confluence to Marshall-Petaluma Road, plus one mile of Salmon Creek) No adult coho salmon or coho redds were observed in this reach. One steelhead test redd and one live steelhead were observed in Reach B. Reach C Marshall-Petaluma Road to bottom of Walker Creek Ranch) One adult coho salmon carcass was observed in Reach C. The carcass was just the lower portion of a coho jack 2-year old adult male) that did not have an adipose fin. Two adult steelhead and two 6

7 unidentified live salmonids were observed in Reach C. In addition, ten steelhead redds were observed. Reach D Walker Creek from the confluence of Chileno Creek to Walker Creek Ranch) One adult female coho salmon was observed digging and holding on a redd in this reach. The redd was not measured during this observation and during the next survey the redd was not visible due to a large storm event that caused the redd to become flattened and obscured. In addition, nine steelhead redds and two live steelhead were observed in Reach D. ACKNOWLEDGEMENT This project was funded by the CDFW, Fisheries Restoration Grant Program, in partnership with the National Oceanic and Atmospheric Administration's Pacific Coast Salmon Restoration Fund. MMWD and GANDA would also like to thank the Marin County Office of Education, and the Gambonini, McDonald, and McLaughlin families for granting us access to their properties to conduct the salmon monitoring surveys. REFERENCES Hammack, Lauren Geomorphology of the Walker Creek Watershed: Projects for Habitat Enhancement and Sediment Management. Prepared by Pruneske Chatham, Inc for Marin Resource Conservation District. 56 pp. Hassler, T. J Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates Pacific Southwest) Coho Salmon. U.S. Fish and Wildlife Service Biological Report ). U.S. Army Corps of Engineers. TR EL pp. Kittel, M. CDFW. Personal Communication regarding coho plantings. Marin Municipal Water District Unpublished Data. Provided by Gregory Andrew. 7

8 FIGURES

9 Walker Creek Salmon Monitoring Program Watershed Map Chileno Creek Downstream extent of study area Walker Creek Sonoma County Marin County Frink Canyon Marsha ll-petaluma Rd Verde Canyon Upstream extents of study area Salmon Creek Pacific Ocean San Francisco Bay 1:48, Miles Soulejule Reservoir Source: Pt. Reyes Quad

10 Reach D Snorkel survey area Ê Ch Reach D Ê Electrofishing site Reach break il en o Cr ee k W a lk e r C r ee Reach C k yon C re ek Fr in k C an Reach B S a lmo n Creek Marsh a ll P e t a lum a Rd Cr ee k r ro y o u Sa sa Rea l, A ch A ny on us al Ver de Ca Sa Tomales Tomales Bay Bay State State Park Park Figure 2. Location of 2012 Juvenile Coho Snorkeling and Electrofishing Surveys. Walker Creek, Marin County, California February 2013 Project Location ^ 0 0 Meters 1, ,500 Feet 5,000, A rr oy o

11 Wal C r eek Coho Redd Steelhead Redd Reach Break r C reek ke Walker Creek C hile no Reach D Ch i le no Cr eek Reach C Reach B Ca ny on Cr eek F ri nk ch A A r ro ^ ,000 Meters 1,000 Feet 4,000 Sa Walker Creek, Marin County, California February 2013 Project Location yo l us a, Rea Ca n yon Verd e Cre ek Figure 3: Survey Reaches and Redd Observations from Adult Coho/Steelhead Surveys al m o n C r eek S

12 APPENDICES

13 Appendix A. Summary of Fish Captured during the 2012 Juvenile Electrofishing Survey in Walker Creek. Electrofishing Survey Area Date A 10/30/12 B 10/30/12 Drainage Walker Creek Walker Creek Habitat Type # Coho Captured Size/Size Range mm) # Steelhead Captured Size/Size Range mm)* Roach Sculpin Three spined Stickleback Pool 0 n/a no measure Pool 0 n/a

14 Appendix A continued. Summary of Fish Captured during the 2012 Juvenile Electrofishing Survey in Walker Creek. Electrofishing Survey Area Date C 10/30/12 Drainage Walker Creek Habitat Type # Coho Captured Size/Size Range mm) # Steelhead Captured Size/Size Range mm)* Roach Sculpin Three spined Stickleback Pool 0 n/a TOTAL 0 n/a * Note: Steelhead >100mm = 1+ age class; Steelhead <110mm = 0+ age class.

15 Appendix B. Fish Observed during the Adult Spawner Surveys in Walker Creek. Date Reach Observation # COHO SALMON 11/20/12 A/B/C/D None Certainty of ssp ID 1 Live or Carcass Sex Certainty of sex ID 1 Fish on Redd? yes/no Redd #) 12/10/12 D WC F D Live F 1 Yes WC R D01) 1/3/13 C WC C C01 1 Carcass 3 No Notes Female coho holding on redd and swam off but returned to redd and continued digging; redd size being enlarged. Coho carcass only the lower half of fish remaining; caudal not spotted; no adipose fin present. 1/15/13 A/B/C/D None 1/31/13 A/B/C/D None STEELHEAD 11/20/12 A/B/C/D None 12/10/12 A/B/C/D None 1/3/13 B WC F B01 1 Live 3 No ~17 inches 1/3/13 C WC F C04 1 Live 3 No ~26 inches 1/31/13 C WC F C03 1 Live 3 Yes WC R C05) Just upstream of redd WC R C05. 1/31/13 D WC F D02 1 Live 3 No 1/31/13 D WC F D03 1 Live 3 No UNKNOWN 1/3/13 C WC F C02 3 Live 3 No 1/3/13 C WC F C05 3 Live 3 No Notes: 1. Certainty of species/sex ID: 2. Observation location type 1 = Sure distinguishing characteristics confirmed). F = Live Fish 2 = May be one species or another coho or steelhead) or one sex or the other; no distinguishing characteristics) observed. 3 = Unknown. C = Carcass

16 Appendix C. Morphology of Redds identified during the Adult Spawner Surveys in Walker Creek. Pot Dimensions m) Tail Spill Dimensions m) Total Dimensions m) Date COHO SALMON Reach Field Numbering 11/20/12 A/B/C/D None Redd # L m) W m) D m) L m) W1 m) W2 m) L m) W m) 12/10/12 D WC D01 WC R D Yes 1/3/13 A/B/C/D None 1/15/13 A/B/C/D None 1/31/13 A/B/C/D None STEELHEAD 11/20/12 A/B/C/D None 12/10/13 A/B/C/D None 1/3/13 B WC B01 WC R B No 1/3/13 C WC F01 WC R C01 n/d 3 n/d n/d n/d n/d n/d No 1/3/13 C WC C06 WC R C " " " No 1/3/13 D WC D02 WC R D02 n/d n/d n/d " " " No 1/3/13 D WC D03 WC R D03 " " " " " " No 1/15/13 C WC C01 WC R C02 n/d n/d n/d n/d n/d n/d No 1/15/13 C WC C02 WC R C03 " " " " " " No 1/15/13 C WC C03 WC R C04 " " " " " " No 1/15/13 C WC C07 WC R C No 1/15/13 C WC C08 WC R C n/d n/d n/d No 1/15/13 D WC D04 WC R D04 n/d n/d n/d " " " No 1/15/13 D WC D05 WC R D05 " " " " " " No 1/15/13 D WC D06 WC R D06 " " " " " " No 1/15/13 D WC D07 WC R D07 " " " " " " No 1/15/13 D WC D08 WC R D08 " " " " " " No Fish on Redd? yes/no

17 Appendix C continued. Morphology of Redds identified during the Adult Spawner Surveys. Date Reach STEELHEAD continued Field Numbering Pot Dimensions m) Tail Spill Dimensions m) Total Dimensions m) Redd # L m) W m) D m) L m) W1 m) W2 m) L m) W m) 1/31/13 D WC D09 WC R D09 n/d n/d n/d n/d n/d n/d No 1/31/13 D WC D10 WC R D10 " " " " " " No 1/31/13 C WC C04 WC R C05 7 " " " " " " Yes 1/31/13 C 1/31/13 C WC C07 amended) WC C07 amended) Fish on Redd? yes/no WC R C " " " No WC R C " " " No Notes: 1. Female coho holding on redd and swam off but returned to redd and continued digging; redd size being enlarged; irregular pit. 2. Test redd, likely steelhead. 3. n/d = no data collected 4. Probable steelhead redd. 5. Likely steelhead redd. 6. Likely steelhead redd. 7. Steelhead adult just upstream. 8. Test redd adjacent to original redd at WC R C07. Likely steelhead. 9. Likely steelhead redd adjacent to original redd at WC R C07.