Loading...
HomeMy WebLinkAboutBradley Lake Salmon Escapement 1985"RECORD COPY" RETURN TO BRADLEY O&M FILES -- 1985 SALMON ESCAPEMENT SURVEY REPORT -·' BRADLEY LAKE HYDROELECTRIC PROJECT BRADLEY RIVER . KENAI PENINSULA, ALASKA FEDERAL ENERGY REGULATORY COMMISSIO N PROJECT NO . P-8221 -000 Alaska Power Authority_ Hydro/Wood/Coai/Solar/Wind/Geothennai/Conseroation Bradley Lake Hydroelectric Project 1985 Salmon Escapement Survey Report Prepared For Stone & Webster Engineering Corporation 800 A Street Anchorage, Alaska Prepared By Northern Technical Services, Inc. December 1985 TABLE OF CONTENTS 1.0 INTRODUCTION •••.•• 2.0 MATERIALS AND METHODS. 2.1 Hoop Nets 2.2 E1ectroshocker • 2.3 Other Fishing Techniques •• . . . 2.4 Data Collection . . . . . . . . . 3.0 RESULTS. 4.0 DISCUSSION • . . . . . . . . . . . . . 5.0 RECOMMENDATIONS . . . . . 6.0 REFERENCES •••• . . . . . . APPENDIX A. Bradley River Salmon Survey Catch and Statistics Data. i 1 2 2 4 4 6 7 11 15 17 LIST OF FIGURES Figure Page l. Area map of lower Bradley River showing location of base camp, hoop trap sites and electrofishing area surveyed in the 1985 salmon escapement survey . . . . . . . . . . . . . . . . . . . . . 3 2. Detail of electrofishing sites surveyed August 22-28, 1985, as part of the salmon escapement survey. A-Riffle Reach: B-hoop net trap area • 5 LIST OF TABLES Table 1. Summary catch record by hoop net traps on the lower Bradley River, August 1-28, 2. 198 5 . . . . . . . . . • . . • . . Summary of catch record for backpack electroshocker, lower Bradley River, August 22-28, 1985 ••••.•••.• iii 8 9 1.0 INTRODUCTION The Bradley Lake Hydroelectric Project is located at the head of Kachemak Bay approximately 27 air miles from the city of Homer. Completion of this project will reduce and stabilize the flow of water in the lower Bradley River and potentially affect salmon runs in the river. As part of project design, the Bradley River system is currently the focus of extensive hydrologic and environmental studies. A salmon escapement survey was conducted in August 1985 on the lower Bradley River as part of these continuing studies. The survey was based primarily on hoop net and electroshocker techniques. While the focus of the study was to enumerate pink salmon escapement, the report discusses all fish captured in the study. Field data collected during the study have been tabulated in Appendix A. 1 . I I 2.0 MATERIALS AND METHODS 2.1 Hoop Nets Hoop nets were utilized in arrays of ten nets deployed in the river at two locations. The downstream array was positioned at approximately River Mile (RM) 3.7, downstream of a large rock where the base camp was located (Figure 1). The upstream array was positioned above Hooligan Slough at approximately RM 4.0. In these areas the Bradley River is subject to tidal fluctuations with some current reversal at the lower station. The hoop nets were serviced on a daily basis, weather permitting, by on-site project personnel. The hoop net traps were constructed of 2-1/2 inch hexagonal wire mesh and were three feet in diameter by eight feet long. A wire mesh cone, with a seven-inch diameter throat, formed the entrance to the trap. The back panel was constructed so that one half of it could be opened to remove captured fish. The back hoop was also rigged with a short line tied to a heavy shackle. In order to hold the hoop net in position in the current, the shackle was dropped over the end of a steel rod ("re-bar"} which had been driven into the substrate. Pink salmon in turbid waters tend to orient with the river bottom and move up-current to the spawning grounds, avoiding the fastest water flow in the middle of the channel. Therefore, the traps were arrayed five from each bank toward the center of the river. Their positions were chosen to: a. Cover as much of the migration corridor as possible: b. Allow complete submergence of the shallowest traps - at low tide: and c. Present the most uniform sampling array possible to migrating fish. 2 I I I i I I LOWER TRAP SITE 0~5iiiii500ft. SCALE RIFFlE REACH ELECTROFISH AREA Figure 1. Area map of lower Bradley River showing location of base camp, hoop trap sites and electrofishing area surveyed in the 1985 salmon escapement survey. 3 2.2 Electroshocker Electrofishing was performed in the Riffle Reach area (Figures 1 and 2) at approximately RM 4.7. Sampling was also conducted in the vicinity of the hoop net arrays at RM 3.8 and 4.0. A backpack Smith-Root Model XII electrofisher, set at 700-900 VDC, 60 Hz was used. Two field crew members performed the survey either by wading along the shore or drifting through the reach in mid-channel from a tethered boat. At the hoop net sites, 1000- 2000 ft 2 was fished during each effort; whereas in Riffle Reach, 1000-3000 ft 2 was fished. Electrofishing effort was concen- trated at Riffle Reach because river characteristics in this reach were best suited to operational requirements of the backpack shocker equipment. 2.3 Other Fishing Techniques During the first three days of the field effort, both dip net and seine techniques were employed to assess whether pink salmon were present in the river at the beginning of the survey. Dip netting was conducted at Tree Bar Reach on August 1. The south bank was _systematically sampled for a distance of approximately 500 feet, from shore to a water depth of three feet, with a large salmon landing net. A 100 X 4 ft, 1/4 inch square mesh, nylon seine was fished in the lower end of Riffle Reach on the same day. One end of the seine was fixed on shore and then the free end extended across the river and allowed to drift downstream. During this drift, the shore fast end was moved approximately 50 yards downstream. The free end of the seine was then brought to shore and the seine retrieved. 4 RFR...E REACH LOWER TRAPS 8 N.JT lFPER TRAP AREA 100" x 10' LEGEND ARR -ABOVE RIFFLE J -- REACH EPR -EAGLE POOL REACH MRR -MID RIFFLE REACH OPN-OATAPOO SITE. NORTH BANK AL T -ABOVE LOWER TRAP SITE AUT -ABOVE UPPER TRAP SITE NOT TO SCALE Figure 2. Detail of electrofishing sites surveyed August 22- 28, 1985, as part of the salmon escapement survey. A -Riffle Reach; B -hoop net trap area. 5 2.4 Data Collection The following information was recorded from the captured fish: species, sex, general condition, fork length, date of capture, and presence of marks or tags. Two colors of plastic anchor tags were applied to all captured fish to denote collection location. In the case of electrofishing, the date of capture was also coded by tag position since Riffle Reach is a known spawning ground. In addition, water temperature was recorded on a daily basis using an Omega AET 450 digital thermometer accurate to O.l°C. This instrument malfunctioned on the fourth day and was replaced by a mercury glass thermometer. Unfortunately, it arrived with a broken mercury column. It was replaced with another mercury thermometer with a resolution of 0.2°C. Incidental observations were also made on the presence of harbor seals in the lower Bradley River. These observations were initiated during the second week of the study effort. 6 3.0 RESULTS The hoop net traps captured 12 fish at the lower station; they included 11 pink salmon and 1 chum salmon (Table 1). A total of 21 fish were captured at the upper station; they included 15 pink salmon, 5 chum salmon, and 1 silver salmon. There were no recaptures. Daily catch results are listed in Appendix A, Tables A-1 and A-2. The number of recaptures obtained in the hoop net sampling effort was not sufficient to use in estimating the escapement population of pink salmon. A Schumacher multiple mark-and-recapture estimator (Ricker 1975) was used to estimate the population of spawning pink salmon in Riffle Reach from electroshocker data. The electrofishing effort captured 66 fish; they included 65 pink salmon and 1 chum salmon (Table 2). One pink salmon was a recapture. This resulted in a population estimate of 771 pink salmon, with upper and lower 90 percent confidence limits of 3,356 and 435 fish, respectively. An estimate based on the area of the spawning ground is also possible and may be more reliable. Previous studies (Woodward- Clyde Consultants 1983) indicate that Riffle Reach measures approximately 150,000 ft 2 in area. On four of the seven days several locations (DPN and MRR; Figure 2) in Riffle Reach were sampled with a consistent sampling effort (3000 ft 2 was fished). On those days a total of 43 pink salmon were captured resulting in a daily average of 10.75 fish. Assuming that the spawning gravels are of uniform distribution and quality, a proportion can be calculated as follows: 150,000 ft 2 total area of Riffle Reach 3,000 ft 2 spawning ground sampled x 10.75 pink salmon captured (daily avg) = 537 total pink salmon present on the grounds of Riffle Reach. 7 Table 1. Summary catch record by hoop net traps on the lower Bradley River, August 1-28, 1985. Total Pink Chum Silver Station Trap Days Salmon Salmon Salmon Total Fish Lower 224 11 1 0 12 Upper 222 15 5 1 21 Recaptures 0 0 0 0 8 Table 2. Summary of catch record for backpack electroshocker, lower Bradley River, August 22-28, 1985. Location Lower Trap site Upper Trap site Below Riffle Reach Above Riffle Reach Riffle Reach * Total * One recapture at Area Fished (sq ft) 2000 1000 2000 3000 3000 No. Days No. Fish No. Fish Fished Observed Captured Species 2 0 0 2 0 0 2 15 10 Pink salmon 2 15 6 5 Pink salmon, 1 Chum salmon 4 144 50 Pink salmon 17 4 66 this location. 9 Both dip nettinq and seining techniques were employed on spawning grounds of the Bradley River. Tree Bar Reach was sampled by dip net on August 1. Approximately 500 feet of shoreline was sampled out to a water depth of 3 feet. A total of six fish were captured in this effort. Three of the fish were captured at the head of Tree Bar Reach and three from the lower end. All fish were in very good condition. No data were collected from these fish since the technique was employed only to assess whether pink salmon were present in the river system at the start of the field sampling effort. Seining was conducted on Riffle Reach on the same day to assess whether pink salmon were in this spawning reach as well. One seine haul was made through the lower half of the reach to approximately mid-river. This haul resulted in the capture of one pink salmon and one juvenile dolly varden; three fish were also observed escaping from the seine. 10 4.0 DISCUSSION The 1985 spawning run of pink salmon was the returninq 1983 year-class. In Kachemak Bay the odd-year runs of pink salmon are usually larger than the even-year runs (Alaska Power Authority 1985). However, the Bradley River is reported to have sustained an unusually large spring flood in 1983 which scoured the riverbed and may have killed many pink salmon fry before they were ready to outmigrate (Woodward-Clyde Consultants 1984). Therefore, the results of the 1985 salmon escapement survey may reflect an unusually low return of pink salmon spawners. Population estimates for the 1985 run of Pink salmon are based on the electrofishing data. Certain assumptions were made in the analysis of these data. 1. Tags are not lost from the fish. This assumption was reliable because the tag scar would have been recognized, even if the tag itself were lost. 2. Tagged and untagged fish suffer the same mortality. 3. Tagged and untagged fish are equally vulnerable to capture. 4. All marks are recognized and reported. 5. Negligible recruitment or migration occurs during the study. This assumption was not reliable. 6. The marked fish become randomly mixed with the unmarked fish. This assumption could not be verified. The tagged fish were free to mix with through migrants, and to leave the sampling area. 11 7. The areas selected for electrofishing were repre- sentative of the spawning grounds in Riffle Reach. This assumption could not be verified. The sampling areas were selected based on accessibility to the sampling techniques. The population estimates derived in this study were 537-771 pink salmon in Riffle Reach. If it can be assumed that the density of spawning salmon in Tree Bar Reach (the other major spawning ground in the Bradley River) is the same as in Riffle Reach, then an extrapolation can be calculated. The spawning area of Riffle Reach is half that of Tree Bar Reach (Woodward-Clyde Consultants 1983). Multiplying the Riffle Reach estimates by 3 (to achieve an estimate of the total) yields a range of 1,611-2,313 pink salmon in the Bradley River in August 1985. The estimates of the 1985 pink salmon spawning run (1,600-2,300 fish) are consistent with the estimates made by previous in- vestigators (Corps of Engineers 1982, 1985; Woodward Clyde Consultants 1983). In fact, the 1985 run may have been toward the low end of the odd-year range. Based on the 1985 estimates and on the apparent proportion of chum to pink salmon in the August 1985 catches, there may be a greater chum salmon run in the Bradley River than previously estimated. However, the data are inconclusive due to the low number of fish captured. In this study, 6 chum salmon and 26 pink salmon were captured in the hoop net traps. Since the 1985 estimate of the pink salmon run is consistent with other invest- igations, one might assume that the percentage of chum to pink salmon (23%) may be the same; this implies that a run of several hundred chum salmon may exist. However, existence of such a chum population is not supported by the electrofishing data. Only one chum was captured during electrofishing at Riffle Reach. This may be due in part to the fact that chum salmon run earlier in the season than pinks or that chums captured in lower river traps could have been strays milling from other areas such as Fox Farm 12 Creek. Over 100 chums were visually counted in Fox Farm Creek in early August. The chums may be milling throughout the lower Bradley River, or they may have been chased past Fox Farm Creek by the many seals sighted near the mouth of the Bradley River (see Appendix A, Table A-8), and therefore encountered the traps more frequently than the pinks. Surface water temperatures were collected throughout the study period at the lower trap site (Appendix A, Table A-7). Although several equipment malfunctions limited data collection, tempera- ture values ranged from 7.4 to 9.6°C throughout this field sampling program. This range is consistent with other data collected on the lower Bradley River. During August 1985 temperature data were also recorded by three temperature data re- corders located at Riffle Reach, Tree Bar Reach, and North Fork Bradley River. The temperature ranges recorded from these three stations for the month of August were 6.9 to 8.8°C, 7.3 to 9.5°C, and 5.5 to ll.0°C, respectively. Complete temperature records are contained in a separate water quality data report (NORTEC 1985). These temperature records are similar to data collected by Woodward-Clyde Consultants (1983) where August temperatures for the lower Bradley River were reported to range from approximately 6.5°C to l0.0°C. The 1985 field season showed that common salmon sampling method- ologies were not as effective (measured in total numbers col- lected) on the Bradley River as they are on rivers with larger runs of salmon. This was in part due to the physical limitations imposed on sampling in the lower tidal reaches of the river. Specific sampling information gained from this field season include: l. The run of spawning pink salmon probably began before the start of sampling on August l in 1985. 13 2. There is no way to discriminate Bradley River spawners from fish straying (or chased by seals) into the lower Bradley from other nearby river systems. 3. The small population will require disproport- ionately greater sampling effort to estimate size with a reasonable level of certainty. 4. The hoop nets were unreliable due to clogging by debris and detritus, reversin9 current at the lower stations, and large tidal fluctuations. 14 5.0 RECOMMENDATIONS The following recommendations are made based on the assumption that monitoring of pink salmon populations will be a requisite component of the Bradley Lake Hydroelectric Project. 1. Future sampling techniques should capture a greater proportion of fish to yield more accuracy and precision in population estimates. This may require a technique which collects nearly all spawners. 2. The sampling period should be expanded to address chum salmon spawners and to identify the time period in which pink salmon spawners return to Bradley River. 3. Survey efforts should focus on upstream areas near or on the spawning grounds to reduce the potential for sampling "strays" and to minimize the influence of tides. Two alternative population sampling techniques are discussed below: The first alternate involves seining the spawning grounds (Riffle Reach, Tree Bar Reach, etc.) once or twice per week during the summer. A multiple mark-and-recapture estimator (Schumacher-type) may then be applied to all species of fish on the spawning grounds. This would eliminate the problems of stray fish~ the loss of stationary sampling gear due to debris, currents, or weather; and uncertainty about the number of other species of fish using the lower river. The second alternate technique would be to census (rather than estimate) the population as fish enter the spawning grounds. A one-wing fyke-type net could be positioned at the lower end of Riffle Reach. The heart of the trap would be in deep, slow- 15 moving water. The fish captured in the fyke trap would be tagged, identified, enumerated, and released above the wing. A wier and trap would be equally effective in this approach. 16 6.0 REFERENCES Alaska Power Authority. 1985. Mitigation Plan-Bradley Lake Hydroelectric Project. November 1985. Corps of Engineers. 1982. Bradley Lake Hydroelectric Project, Alaska, Final Environmental Impact Statement. Department of the Army, Alaska District Corps of Engineers, Anchorage, Alaska. August 1982. 184 p. with appendices. Corps of Engineers. 1985. Bradley Lake Hydroelectric Project, Alaska, Final Supplemental Environmental Impact Statement. Department of the Army, Alaska District Corps of Engineers, Anchorage, Alaska. September 1985. 158 p. with appen- dices. Northern Technical Services, Inc. (NORTEC). 1985. Bradley Lake Hydroelectric Project Environmental Monitoring Program Water Quality Data Report -August 1-31, 1985. Unpublished report submitted to Stone and Webster Engineering Corporation, 800 "A" Street, Anchorage, Alaska. 2 p. plus attachments. Ricker, W.E. 1975. Computation and interpretation of biological statistics of fish populations. Bull. Fish. Res. Board Can. 191: 1-382. Woodward-Clyde Consultants. 1983. Bradley River instream flow studies. Prepared for Alaska Power Authority, Anchorage, Alaska. 77 p. with appendices. Woodward-Clyde Consultants. 1984. Report on salmon fry sampling in the Bradley River. Prepared for Alaska Power Authority, Anchorage, Alaska. 6 p., with tables and figures. 17 APPENDIX A Bradley River Salmon Survey Catch and Statistics Data August:t-1985 LIST OF TABLES Table A-1 Lower Hoop Trap site Catch Data for the Bradley River, August 1-28, 1985 •.•••• A-1 A-2 Upper Hoop Trap site Catch Data for the Bradley River, August 1-28, 1985 •••..• A-2 A-3 Catch Statistics for Captured Salmon at the Lower Hoop Trap site Bradley River, August 1-28, 1985. • • • • • • • • • • • A-3 A-4 Catch Statistics for Captured Salmon at the Upper Hoop Trap site Bradley River, August 1-28, 1985 ••••••••••••• A-4 A-5 Backpack Electroshocker Catch Data for the Bradley River, August 22-28, 1985. • A-5 A-6 Catch Statis~ics for Captured Salmon using Backpack Electroshocker in the Riffle Reach Area of the Bradley River, August 22- 28, 1985 • • • • • • • • • • • • • A-7 Surface Water Temperature Recorded during Lower Bradley River Salmon Survey, • A-6 August 1-28, 1985 ••••••••••• A-9 A-8 Incidental Harbor Seal Sightings in the Lower Bradley River during Salmon Survey, August 1-28, 1985 ••••••••••••• A-10 A-i Table A-1. Lower Hoop Trap site Catch Data for the Bradley River, August, 1-28, 1985. Date 8-1 8-2 8-3 8-4 8-5 8-6 8-7 8-8 8-9 8-10 8-11 8-12 8-13 8-14 8-15 8-16 8-17 8-18 8-19 8-20 8-21 8-22 8-23 8-24 8-25 8-26 8-27 8-28 TOTAL #: Trap Days 10 10 10 9 10 10 10 10 9 9 9 9 7 7 6 6 2 2 2 5 5 9 9 9 10 10 10 10 224 If Fish Captured 0 0 0 0 0 0 0 3 0 0 2 0 0 0 0 3 0 0 1 0 0 2 0 0 1 0 0 0 12 A-1 Species Pink Salmon Pink Salmon 2 Pink Salmon 1 Chum Salmon Pink Salmon Pink Salmon Pink Salmon Table A-2. Upper Hoop Trap site Catch Data for the Bradley River, August 1-28, 1985. fl: Trap # Fish Date Days Captured Species 8-1 0 0 8-2 8 0 8-3 8 0 8-4 8 2 Pink Salmon 8-5 8 0 8-6 8 2 1 Pink Salmon 1 Chum Salmon 8-7 10 0 8-8 10 6 2 Pink Salmon 4 Chum Salmon 8-9 8 0 8-10 8 0 8-11 8 0 8-12 8 0 8-13 7 0 8-14 7 0 8-15 7 0 8-16 7 1 Pink Salmon 8-17 7 0 8-18 7 4 Pink Salmon 8-19 7 8-20 7 1 Pink Salmon 8-21 7 0 8-22 9 3 2 Pink Salmon 1 Silver Salmon 8-23 9 0 8-24 9 0 8-25 10 0 8-26 10 0 8-27 10 2 Pink Salmon 8-28 10 0 TOTAL 222 21 A-2 Table A-3. Catch Statistics for Captured Salmon at the Lower Hoop Trap site Bradley River, August 1-28, 1985. Fork Length Date Species Sex (in) Condition 8-8 Pink M 24.0 Good 8-8 Pink F 19.5 Good 8-8 Pink M 25.0 Good 8-11 Pink M 20.5 Good 8-11 Pink F 20.5 Good 8-16 Pink F 20.0 Dead 8-16 Chum F 21.5 Good 8-16 Pink M 20.5 Good 8-19 Pink F 22.0 Good 8-22 Pink M 21.5 Fair 8-22 Pink M 21.0 Good 8-25 Pink M 20.0 Fair, spawned out A-3 Table A-4. Catch Statistics for Captured Salmon at the Upper Hoop Trap site Bradley River, August l-28, 1985. Fork Length Date Species Sex (in) Condition 8-4 Pink M 19.0 Good 8-4 Pink F 21.5 Dead 8-6 Chum F 23.5 Good 8-6 Pink F 21.0 Good 8-8 Chum F 26.0 Good 8-8 Chum F 25.0 Fair 8-8 Chum M 19.5 Fair 8-8 Chum F 24.0 Fair 8-8 Pink ? 18.0 Good 8-8 Pink M 21.0 Good 8-16 Pink M 20.0 Very Poor 8-18 Pink M 19.0 Poor 8-18 Pink M 19.5 Good 8-18 Pink F 18.0 Good 8-18 Pink M 20.0 Good 8-20 Pink F 18.0 Poor 8-22 Pink M 23.0 Spawned out 8-22 Pink F 19.0 Good 8-22 Silver ? Good 8-27 Pink M 17.0 Poor 8-27 Pink F 16.0 Poor A-4 Table A-5. Backpack Electroshocker Catch Data for the Bradley River, August 22-28, 1985. Area # Fish Sampled Observed # Fish Species Date Location* (sq.ft.) (escaped) Captured Captured 8-22 ARR 3000 6 3 Pink salmon 8-23 ARR 3000 3 3 2 Pink & 1 churn salmon 8-23 EPR 2000 1 6 Pink salmon 8-24 MRR 2000 10 6 Pink salmon 8-25 MRR 2000 13 8 Pink salmon 8-25 DPN 1000 2 1 Pink salmon 8-25 ALT 2000 0 0 8-25 AUT 1000 0 0 8-26 MRR 2000 16 7 Pink salmon 8-26 DPN 1000 5 5 Pink salmon 8-26 AUT 1000 0 0 8-27 MRR 2000 12 5 Pink salmon 8-27 DPN 1000 6 4 Pink salmon 8-27 ALT 2000 0 0 8-28 MRR 2000 24 5 Pink salmon 8-28 DPN 1000 6 9 Pink salmon 8-28 EPR 2000 4 4 Pink salmon TOTAL 108 66 * Key: ARR -Above Riffle Reach EPR -Eagle Pool Reach MRR -Mid Riffle Reach DPN -Datapod Site, North Bank ALT -Above Lower Trap AUT -Above Upper Trap A-5 Table A-6. Catch Statistics for Captured Salmon using Backpack Electroshocker in the Riffle Reach Area of the Bradley River, August 22-28, 1985. Fork Length Date Species Sex ( in) Condition 8-22 Pink M 21.0 Good 8-22 Pink F 19.0 Good 8-22 Pink F 21.0 Good 8-23 Pink F 17.5 Good 8-23 Pink F 20.0 Good 8-23 Chum F 21.0 Spawned out 8-23 Pink F 18.0 Good 8-23 Pink F 18.5 Good 8-23 Pink F 18.5 Good 8-23 Pink F 19.5 Good 8-23 Pink F 21.0 Good 8-23 Pink M 20.0 Good 8-24 Pink F 19.5 Very Good 8-24 Pink F 18.5 Very Good 8-24 Pink F 19.0 Very Good 8-24 Pink F 21.5 Very Good 8-24 Pink F 19.5 Very Good 8-24 Pink M 19.0 Good 8-25 Pink F 20.5 Very Good 8-25 Pink F 21.0 Very Good 8-25 Pink F 19.0 Good 8-25 Pink F 20 .5 Very Good 8-25 Pink F 19.0 Good 8-25 Pink M 20.0 Very Good 8-25 Pink F 19.5 Very Good 8-25 Pink M 20 .o Good 8-25 Pink M 21.5 Very Good A-6 Table A-6 (Cont'd). Catch Statistics for Captured Salmon using Backpack Electroshocker in the Riffle Reach Area of the Bradley River, August 22-28, 1985. Fork Length Date Species Sex ( in) Condition 8-26 Pink M 19.5 Good 8-26 Pink M 20.0 Very Good 8-26 Pink M 22.0 Very Good 8-26 Pink M 19.0 Very Good 8-26 Pink F 20.0 Very Good 8-26 Pink F 18.5 Very Good 8-26 Pink M 22.5 Very Good 8-26 Pink F 19.0 Fair 8-26 Pink F 20.5 Fair 8-26 Pink M 18.5 Very Good 8-26 Pink F 18.5 Fair 8-26 Pink F 20.5 Very Good 8-27 Pink F 20.0 Very Good 8-27 Pink F 20.5 Fair 8-27 Pink M 20.0 Very Good 8-27 Pink M 22.0 Good 8-27 Pink M 19.5 Very Good 8-27 Pink F 19.0 Fair 8-27 Pink M 21.0 Fair 8-27 Pink M 20.0 Fair 8-27 Pink F 17.0 Spawned out 8-28 Pink M 21.0 Fair 8-28 Pink M 18.0 Good 8-28 Pink F 19.5 Very Good 8-28 Pink M 18.0 Good 8-28 Pink M 20.0 Good A-7 Table A-6 { Cont 'd) • Catch Statistics for Captured Salmon using Backpack Electroshocker in the Riffle Reach Area of the Bradley River, August 22-28, 1985. Fork Length Date Species Sex {in} Condition 8-28 Pink M 18.0 Fair 8-28 Pink M 20.0 Fair 8-28 Pink* F 18.5 Good 8-28 Pink F 19.5 Fair 8-28 Pink M 19.5 Very good 8-28 Pink M 20.5 Good 8-28 Pink F 21.0 Good 8-28 Pink F 17.5 Good 8-28 Pink M 20.0 Good 8-28 Pink F 19.0 Very good 8-28 Pink M 19.5 Good 8-28 Pink F 18.5 Very good 8-28 Pink F 20.0 Very good * Recaptured (Tagged 8-26-85} A-8 Table A-7. Surface Water Temperature Recorded during Lower Bradley River Salmon Survey, August 1-28, 1985. Date 08-02-85 08-04-85 08-06-85 08-07-85 08-11-85 08-12-85 08-23-85 08-24-85 08-25-85 08-26-85 08-27-85 08-28-85 08-29-85 Temperature (°C) Notes 8.6 9.4 9.4 11.7 7.4 12.8 12.9 13.3 13.5 13.6 13.5 13.8 Data collected with digital thermometer Data collected with digital thermometer Data collected with digital thermometer Thermometer malfunction Mercury column separated on new thermometer, data suspect Mercury column separated on new thermometer, data suspect New mercury thermometer used Checked against another new mercury thermometer and found reading to be 9.6°C. Suspect all readings need to be adjusted down 4.2°C. A-9 Table A-8. Incidental Harbor Seal Sightings in the Lower Bradley River during Salmon Survey, August 1-28, 1985. Number of Date Location* Seals 08-11-85 Fox Farm Creek 1 08-13-85 Fox Farm Creek 1 08-16-85 Fox Farm Creek 1 08-16-85 Base camp 1 08-16-85 River mouth More than 120 08-18-85 Eagle Pool Reach/ 9 Riffle Reach 08-18-85 Base camp 1 08-19-85 Base camp 6 One observed with salmon in mouth 08-20-85 Base camp 4 08-20-85 Fox Farm Creek 1 08-21-85 Base camp 9 08-22-85 Base camp 2 08-22-85 River mouth More than 325 08-23-85 Base camp 3 08-24-85 Base camp 1 08-25-85 Base camp 1 08-28-85 Base camp 5 08-29-85 Base camp 5 * Most sightings were near high tide, + 2 hours. A-10