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HomeMy WebLinkAboutKnutson Cr. FISH SURVEY Report 9,12 (FINAL 1A)Technical Report No. 12-011 __________________________________________________________ A Fisheries Survey of Upper Knutson Creek Associated with Potential Hydroelectric Development for Pedro Bay, Alaska by Bruce M Barrett September 2012 ________________________________________________________________________________ Alaska Biological Consulting PO Box 322 Lakeside, MT 59922-0322 Tel: 406-844-3453 E-mail: alaskabiol@yahoo.com 1 INTRODUCTION Knutson Creek, an inlet stream of Iliamna Lake on the northeast end, is designated as an anadromous fish stream under Alaska Statute 16.05.870 (Figure 1). The stream lies northwest of the community of Pedro Bay, Alaska and is being considered as a potential hydroelectric energy source for the village by the council. Polarconsult Alaska, Inc. is conducting the feasibility study. The proposed project calls for diverting approximately 10-20 cfs of water from Knutson Creek at RM 2.6 and returning the diverted flow at RM 1.2. The need for an alternative energy source for Pedro Bay Village is evident with diesel selling at $6.90/gallon and electricity at 91 cents/kwh there (personal communication, Ben Foss). Lower Knutson Creek is occupied by anadromous and resident fishes based on ADF&G’s Catalog of Waters Important for Spawning, Rearing, and Migration of Anadromous Fishes (2012). The species listed are: Dolly Varden and slimy sculpin (resident fishes) and sockeye salmon (anadromous fish). To properly evaluate the potential impact to fisheries resources from construction and operation of a small-scale hydro power facility on Knutson Creek, it is essential under Alaska Title 16 statutes to determine the extent of resident and anadromous fish use within the proposed project reach (RM 1.2- RM 2.6) and also the level of use by subsistence and recreational fishers. This report is intended to serve that purpose. OBJECTIVES The objectives of this study were: 1. Determine fish presence by species and their approximate distribution in upper Knutson Creek from about RM 1.2 to 2.7 (approximately 1.5 miles); 2. Determine average fish size by species in the study reach, excluding sculpin and adult sockeye salmon; 3. Classify the general stream characteristics within the study reach; 4. Determine whether upper Knutson Creek is used by local residents for subsistence and/or sport fishing; 5. Identify potential fish mitigation alternatives. METHODS A standard salmon escapement survey was conducted on foot with the observer using polarized glasses and a tally counter. Counts (live fish and carcasses) by species were recorded per ¼ mile stream reach beginning at approximately RM 1.25 and extending upstream to RM 2.7 (Figure 2). The upper most point of observed adult salmon presence was documented by GPS. Ten standard minnow traps were deployed at multiple locations in upper Knutson Creek with one in a tributary near its Knutson Creek confluence and seven traps within the proposed main-stem project reach and two about 0.2 miles further upstream (above the proposed hydro-intake) in the area of a tributary confluence (Figure 2). Average fishing time per trap was 6.4 h (range: 0.9-21.5 h). Trap bait consisted of sockeye salmon (Oncorhynchus nerka) roe provided by a Pedro Bay sport-fishing lodge. Each trap was baited with two sections of roe (approx. 20 g/each) individually secured in a cheesecloth wrap. All baits were disinfected by a 10-m soak time in 1/100 Betadyne, and each trap site was a low velocity location, typically behind boulders along the stream bank. All traps deployed were weighted with one or two medium size cobble and secured by a line attached to the shore. Trap locations were identified by GPS and flagged for visual identification. 2 Fish captured were confirmed by species in accordance with Pacific Fisheries of Canada (1973). A total of 129 Dolly Varden (Salvelinus malma) from the traps were measured for FL (tip of snout to fork-of tail, mm). Two larger caught Dolly Varden were examined for maturity. Rearing fish presence was also evaluated by visually inspecting low velocity near-shore bank areas and pools in secondary mainstem flow channels between the powerhouse area and the proposed hydro-intake on the creek’s right side (looking upstream). The left (west) side of Knutson Creek was not assessable due to stream flow conditions. Fish sampling was conducted incompliance with an ADF&G issued collection permit (SF2012-266), and field assistance was provided by Vern Jensen while logistical support at Pedro Bay was given by Ben Foss and daughter. RESULTS Resident Fish A total of 256 Dolly Varden (DV) were captured in 10 minnow traps deployed for 58 hours in the study area, and all traps produced a catch (Tables 1-2; Figure 3). The DV captured were considered resident fish given size and sexual maturity. The average FL measured was 11.9 mm (4.7”) and the range was 5.8- 19.3 mm (2.3- 7.6”; Tables 3-4). Of two DV sampled for maturity, both were found to be sexually mature (Figure 4.) No other resident fish species were caught or observed in Knutson Creek with the exception of approximately six young-of-year (YOY) fish which were likely sculpin (Cotus sp.) in an elevated flow channel off the left side of Knutson Creek mainstem between trap sites #1 and #2 (RM 1.6-1.7). These YOY fish, visually judged to be juvenile sculpin, were approximately 20 mm in length and displayed a darting type swimming motion when disturbed. At several trap locations, “small” size fish were readily visible and particularly at trap sites T-1 and #9 both of which had a tributary influence. Likewise in many other low velocity areas of the main-stem, “small” fish were readily visible including the reach sampled above the proposed hydro-intake. Based on trap catches and visual assessment, all were considered to be DV. Further, where traps were set at these locations, “small” sized fish were observed entering the traps within minutes of their placement and as defined earlier, all trap-caught fish were DV. Anadromous Fish The upper limit for anadromous fish in Knutson Creek is approximately RM 2.04 as defined in ADF&G’s Catalog of Waters Important for Spawning, Rearing, and Migration of Anadromous Fishes (2012). On August 23, 2012 a total of 43 adult sockeye salmon were counted above RM 1.25 under ideal survey conditions (Tables 2 and 5). Of these, 40 were alive and three were carcasses, one of which was bear-killed (Figures 5-6). All but one of the 40 live fish were either paired or aggregated and all were in spawning condition. Most of the adult sockeye counted were in the immediate area of trap site #2 and split into two aggregates, both within 3 meters of the bank and holding over sandy-gravel substrate in relatively low velocity areas. The furthest adult sockeye salmon observed in Knutson Creek was as at RM 2.1, at a site about 4 meters below the lower gaging station. The sighting was limited to a single male in spawning condition and represents a slightly higher stream location than previously known (ADF&G 2012). No juvenile salmon were caught in any of the 10 minnow traps, indicating their absence in Knutson Creek upstream of about RM 1.25 (Table 2). 3 Fisheries Use Upper Knutson Creek (above RM 1.25) supports minimal bear use based on the low number of adult sockeye observed. Only one bear-killed salmon carcass was found, and there was no evidence of any regular bear-trails, and one scat was observed (Figure 6; 2.5-d of observation (8/23-25/12)). Two (>50yrs/old) male Pedro Bay residents were queried on the communities’ dependence on upper Knutson Creek for subsistence use. Both reported that the upper stream is not currently used nor has it been used in the past. They indicated that the lower river near the lake below RM 0.5, and mainly the river mouth provides recreational and subsistence fishing. General Habitat Observations The stream bed in the proposed project reach is comprised of moderate sized granite cobbles, boulders, and course sands, in order of abundance. No silt deposits were observed and cobble embeddedness was minimal at an estimated maximum of 5% in the near-shore (0-50cm depth). Mainstem water clarity was excellent, fully transparent. While not specifically measured the OHW channel width was visually estimated to average about 1.5x of the stream width in most areas. Knutson Creek water temperature was 45F at trap site #5 (8/23/12; 1227 hrs), and 48F in the tributary at trap site T-1, and 49.5F in a backwater channel of the same tributary where an estimated 40-50 DV in the 7-15 cm FL range were readily visible at the time of trap placement (8/23/12; 0952hrs; Figure 7). Stream gradient was estimated to be about 2-3% in the project reach except for 5-6 % where the stream passes through a canyon at RM 2.0. While no barrier falls were noted several areas from trap site 2 upstream supported a series of cascades with two to four ft. of vertical drop each (e.g. Figures 8-9) that were commonly sparse of fish resting and/or holding areas. While the vertical drops would not likely impede the assent of pre-spawning condition adult salmon, they appeared formidable enough to retard most spawning condition adults such as observed in the area of trap sites #1 and #2. DISCUSSION Fisheries Knutson Creek supports adult sockeye salmon and resident DV in the reach proposed for hydro-electric development. As compared to lower Knutson Creek and the lake-shoals off its stream mouth, the upper stream provides minimal sockeye spawning habitat and use. Peak escapement counts in the lower river and Knutson Bay average about 600 (yrs. 2002-11) and 96,000 (yrs. 2007-11) sockeye salmon, respectively (Morstad, 2012). An estimate of the total 2012 sockeye escapement for the hydro-electric reach can be made by expanding the peak count of 40 live fish by a factor of 2.47 as derived from peak aerial counts and weir and tower escapement numbers from other sockeye systems (Eggers et. al. 2012). Total escapement within the boundaries of the hydro-sockeye salmon project amounts to an estimated 99 sockeye salmon. DV are present throughout the study reach and evidence is that the upper stream offers both rearing and spawning habitats. The former is based on high trap catch numbers and sight observations while the later is based on two sexually mature DV sampled from trap #6 measuring 15.2cm and 15.7 cm (6 and 6.2 inches). The lateral tributaries flowing into Knutson Creek provide DV rearing habitat also as some of the highest minnow trap catches were in and around the mouths of two sampled tributaries. While DV are relatively abundant and well distributed in the project area, they are small in size based on an average 12cm FL (4.7 inches) and are not known to support any fishery (subsistence or sport). 4 The absence of any juvenile salmon in the minnow traps set in upper Knutson Creek was not unexpected particularly for juvenile sockeye fry which typically rear in lakes, sloughs, and ponds where a strong zooplankton forage base exists such as Iliamna Lake (Hart 1973). Any fry produced from stream- spawning sockeye salmon would expectedly descend into Iliamna Lake after emerging in the spring. Because Coho salmon are not known to spawn in Knutson Creek (ADF&G 2012), and adult Coho salmon are not common in either Knutson Bay or Pedro Bay of Iliamna Lake, per local knowledge, explaining why juvenile Coho fry were not caught in Knutson Creek above RM 1.2. Mitigation The first question for mitigation consideration is what level of impact might the proposed project have on fish migration, and spawning and rearing habitats from RM 1.2 to RM 2.6, and further what if any opportunities might be available to mitigate potential impacts? Resident Fish It is unlikely that summer rearing habitat for DV would be adversely impacted. From site observations and trapping most if not all of the rearing occurs within the near-shore (<5 m) where water velocity is manageable. With early May through early October flows in Knutson Creek are expected to be in the 80- 300cfs range (pers. com. Joel Groves), a withdrawal of 15-20 cfs at the intake should have no measurable impact on DV movement and/or rearing during that time irrespective of tributary inputs in the RM 2.6 - 2.1 reach. In winter months, the water withdrawal would reduce mainstem flow likely enough to assume that any eggs or spawn incubating in the mainstem would be lost due to dewatering and freezing. Also some pool areas where DV typically overwinter would likely be reduced or lost particularly in the ½ mile reach between RM 2.6 and 2.1 or the area between the intake and tributary “L1” (Figure 1). Because resident DV are not migrating in the winter, fish passage would not be an issue nor would it be in the spring through fall months when there would be more mainstem flow at RM 2.6 then needed for power generation. While DV would be impacted by the proposed project, the impact level should be negligible considering the amount of habitat upstream and downstream of the project reach. However , compensation in the form of replacement habitat could easily be achieved as a byproduct of anadromous fish, specifically sockeye salmon, mitigation opportunities as addressed below. Anadromous Fish Since sockeye salmon currently spawn above the proposed powerhouse site, albeit in relatively low numbers, some fisheries losses would likely occur if nearly all of the Knutson Creek main-stem flow were divereted for power use during the late fall and winter months. This is under the assumption that the upper stream currently provides suitable spawning conditions for successful egg incubation. The impact would be from reduction of the wetted channel width resulting in redds freezing and causing egg mortality. Naturally, this may already be occurring as the sockeye spawning observed was near the edges of the stream in relatively low velocity and in shallow areas which would make the fertilized eggs susceptible to mortality as mainstem flow naturally decreases with freeze-up. Further, it is not unlikely that most of the sockeye counted in the survey were stray fish produced from lower spawning areas. With thousands of fish spawning in Knutson Bay, a minor level of straying could well explain the presence of 43 adult sockeye salmon in the project reach. University of Washington studies indicate that localized straying does occur and between major Pedro Bay pond groups, sockeye salmon straying averages about 4% (Quinn et. al. 2012). Replacement salmon spawning habitat could be developed offsite at Pedro Bay. Several natural groundwater fed ponds are in and around the village that provide sockeye salmon spawning and some DV rearing. The ponds are relatively shallow (about 26 cm (10.2 inch) average depth) and extensively used by brown and black bears for feeding. Pond P1 as partially shown in Figure 10 and described in Quinn et. al. (2012) extends to within 20 feet of a primary Pedro Bay service road (Figure 1). Land setback from the pond by about 10+ yards could be excavated to a depth of about 5-6 feet to create a small (800ft2) auxiliary pond that when connected by a culvert (30-36 inch dia.) to Pond P1 would provide spawning area for about 5 200 sockeye salmon based on a reported average spawner density in Pond P1 of 0.4 m2 (Quinn et. al. 2012). An excavator and other resources are available at Pedro Bay Village to perform the work, and access would be a non-issue including water quality and sedimentation if standard safeguards are followed. This would include excavating the pond without a connection to Pond P1 until all fill material including the banks of the new pond are well vegetated. The conduit connection would follow and be performed using silt barriers and other standard water-quality control methods. An alternate mitigation proposal is to construct a spawning channel at the tailrace discharge. The design would be dependent upon where the power house is sited, but overall there should be ample ground to provide about 1,000ft 2 of spawning area as replacement habitat for about 100 sockeye salmon in upper Knutson Creek (assumes average spawning density of 1 female/2 m2 in Bristol Bay streams (Groot and Marcolis 1991)). The advantage of a spawning channel is flow stability and less erosion than the creek’s mainstem. Further, a spawning channel would provide direct onsite mitigation therein lessening the impact to upper Knutson Creek sockeye salmon, assuming that sockeye production is occurring in the stream’s upper reaches which may not be the case, for reasons addressed earlier. LITERATURE CITED Alaska Department of Fish and Game. 2008, updated 2012. Catalog of waters important for spawning, rearing, and migration of anadromous fishes. ADF&G, Sport Fish Div., Juneau, AK. Eggers, D., Munro, A., and Volk, E., 2012. Estimating escapement of western Alaska sockeye salmon for wassip reporting groups, 2006 to 2008. Tech. Doc. 18, Western Alaska Salmon Stock Identification Program, ADF&G, Juneau, AK. Groot, C. and Margolis L. 1991. Pacific salmon life histories. UBC Press, Vancouver, BC. Hart, J.L. 1973. Pacific fishes of Canada. Bull. 180; Fish. Res. Bd. Canada. Morstad, Steve. 2012. ADF&G salmon escapement survey database ,download June 23, 2012. ADF&G, Div. Comm. Fish., King Salmon, AK. Ouinn, Thomas P. Jr., Gosse, D., and Schtickzelle N., 2012. Population dynamics and synchrony at fine spatial scales: a case history of sockeye salmon (Oncorhynchus nerka) population structure in Alaska, USA. Can. J. Fish. Aquat. Sci. 69: 297–306. ` 6 Table 1. Summary of minnow trap catch results in total number of fish, and average hourly catch by location, date, and species, Knutson Creek, near Pedro Bay, 2012. TRAP Dates Total TOTAL CATCH Avg. Hourly #LOCATION Fished Hours DOLLY other Catch VARDEN Dolly Varden T-1*N 59 48.786 8/23/2012 7.77 39 0 5.0 W 154 07. 361 1 N 59 48.846 8/23/2012 6.75 71 0 10.5 W 154 07. 341 2 N 59 49.069 8/23/2012 5.72 34 0 5.9 W 154 07. 039 3 N 59 49.146 8/23/2012 4.90 6 0 1.2 W 154 06. 889 4 N 59 49.172 8/23/2012 4.00 34 0 8.5 W 154 06. 850 5 N 59 49.195 8/23/2012 3.47 19 0 5.5 W 154 06. 870 6 N 59 49.204 8/23/2012 2.65 14 0 5.3 W 154 06. 789 7 N 59 49.507 8/24/2012 0.87 17 0 19.5 W 154 06. 502 8**N 59 49.598 8/23/2012 0.38 1 0 2.6 W 154 06. 403 8/24/2012 **1 0 ** 9 N 59 49.598 8/23/2012 0.22 6 0 27.3 W 154 06. 403 8/23-24/2012 21.25 14 0 0.7 TOTALS 57.98 256 0 Average 8.4 * Site in lateral tributary 50yds upstream of Knutson Cr. confluence ** Trap dislodged from site found x-wise in stream 7 Table 2. Fish catch numbers by species using a standard minnow trap by location, Knutson Creek, an Iliamna Lake inlet stream near Pedro Bay Village, August 23-24, 2012. TRAP CATCH #LOCATION DATE TIME DOLLY other Notes VARDEN **T-1 N 59 48.786 8/23/2012 0952 hrs Elv. 210 ft. W 154 07. 361 **Side channel of right-bank tributary (R1) 50 yds above Knutson Cr. confluence; trib. water temp.: 48F; side channel: 49.5F Bank veg.: alder and willow, dense Stream bed: cobble 90%, 10% boulder 8/23/2012 1738 hrs.39 0 surface vel: 2.4 ft/sec approx. Trib.input to main stem about 2% volume 1 N 59 48.846 8/23/2012 1022 hrs ELV: 243ft. W 154 07. 341 Right-bank trap set behind large boulder Sockeye adults: 17 live & 1 carcass (bear kill) in immediate area; spawning Excellent survey conditions; water clear 8/23/2012 1723 hrs.71 0 All spawning w/i < 10ft. of stream bank 2 N 59 49.069 8/23/2012 1106 hrs Elv. 277 ft. W 154 07. 039 Right-bank set Alder/willow & cottonwood bank veg. Trap in 18" depth Sockeye adults: 22 live, 2 carcasses counted between trap site 1& 2; spawning 8/23/2012 1649 hrs.34 0 3 N 59 49.146 8/23/2012 1138 hrs Elv. 294 ft. (est.) W 154 06. 889 Loc. at lower stream gage station Set behind bank boulder; 20inch depth Right-bank set Boulder (5ft dia.) and cobble bed 8/23/2012 1630 hrs.6 0 Sockeye adult: 1 live 4m downstream 4 N 59 49.172 8/23/2012 1205 hrs Elv. 304 ft. W 154 06. 850 Loc. at upper (2nd) gage station Boulder/ cobble bed Trap depth: 18 in. 8/23/2012 1605 hrs 34 0 Site across from left-side trib. (L1), approx 5% of mainstem flow 5 N 59 49.195 8/23/2012 1227 hrs Elv. 309 ft. W 154 06. 870 Water temp: 50F Trap depth: 18 in. Bank veg: alder(50%) and willow (50%) Bed: Boulder cobble w/ course sand in eddies Right-bank set 8/23/2012 1555 hrs 19 0 6 N 59 49.204 8/23/2012 1247 hrs Elv. 356 ft. W 154 06. 789 Right-bank set behind table boulder (6X2X12ft.) Bank veg: alder(50%) and willow (50%) 8/23/2012 1526 hrs 14 0 DV 6.0 and 6.2in. (fl) mature male & female 8 Table 2. Page 2 of 2. TRAP CATCH #LOCATION DATE TIME DOLLY other Notes VARDEN 7 N 59 49.507 8/23/2012 1334 hrs Elv. 384 ft. W 154 06. 502 Bank veg: alder(50%) and willow (50%) Right-bank set Bed: cobble/boulder/ course sand Trap depth: 15in. 8/24/2012 1128 hrs **Trap clasp sprung catch lost; trap baited/reset 1220 hrs 17 0 8 N 59 49.598 8/23/2012 1417 hrs ELV. 402 ft; immediately below right-side trib. (R2) W 154 06. 403 1440 hrs 1 0 trap depth:16 in. Right-bank set 8/24/2012 1142 hrs 1 0 8/24/12: Trap found 3yd. downstream cross- wise in current making trap unfishable. 9 N 59 49.598 8/23/2012 1415 hrs Elv. 403 ft. W 154 06. 403 8/23/2012 1428 hrs 6 0 Upstream of proposed hydro-intake Immediately above rt.-side trib. (R2) Trib: adds approx. 20-30% of mainstem flow 8/23/2012 1440 hrs **reset trap; bank veg.: 60% willow, 35% alder, 2-5% spruce 8/24/2012 1155 hrs 14 0 Right bank set; 20 inch depth 9 Table 3. Sampled fork lengths (cm) of Dolly Varden captured, by selected minnow trap, in upper Knutson Creek, an Iliamna Lake inlet stream near Pedro Bay Village, 8/23-24/2012. Specimen Trap Trap Trap Trap Trap Trap Trap Number # 2 # 3 # 4 # 5 # 6 # 8 # 9 1 6.4 11.9 8.6 14.2 10.4 15.9 15.2 2 10.2 10.9 10.7 15.2 14.2 11.4 14.2 3 9.9 14.0 10.2 11.9 13.7 13.2 4 10.9 12.7 11.4 10.7 11.9 12.2 5 10.4 13.7 12.7 14.7 12.7 11.2 6 9.7 12.4 12.2 15.0 9.9 11.2 7 10.9 11.9 13.5 9.7 13.0 8 11.7 13.2 11.7 10.2 11.4 9 6.9 12.7 13.5 10.9 12.7 10 13.2 11.7 11.9 7.4 17.0 11 7.4 16.3 8.9 12.4 13.5 12 9.9 11.7 15.0 11.4 16.8 13 9.4 13.2 11.2 15.2 11.4 14 12.2 19.3 10.9 15.7 15.0 15 11.2 13.7 11.7 12.4 16 15.5 13.0 11.4 12.2 17 14.5 11.7 12.2 12.4 18 11.7 11.4 10.2 13.7 19 5.8 13.7 5.8 12.7 20 12.2 14.7 14.7 21 11.7 15.5 22 12.4 13.2 23 13.0 11.9 24 11.4 9.4 25 10.2 8.6 26 10.9 9.1 27 9.4 12.2 28 10.7 11.7 29 8.6 11.9 30 10.9 12.2 31 8.9 12.7 32 10.2 7.4 33 15.5 9.1 34 8.9 12.7 10 Table 4. Selected length (FL) statistics on Dolly Varden sampled on upper Knutson Creek, an Iliamna Lake inlet stream near Pedro Bay Village August 23-24, 2012. Sample Size Mean Median Range Standard (n)cm inches cm inches cm inches deviation (mm) 129 11.9 4.7 11.9 4.7 (5.8 - 19.3)(2.3 - 7.6)2.3 Table 5. Salmon escapement survey of upper Knutson Creek , by species, from RM 1.25 to RM 2.7, August 23, 2012. River Mile Reach Survey Sockeye Salmon other Start End Conditions Live Dead Total Live Dead Total 1.25 1.50 Excellent 17 1 18 0 0 0 1.50 1.75 Excellent 4 1 5 0 0 0 1.75 2.00 Excellent 18 1 19 0 0 0 2.00 2.25 Excellent 1 0 1 0 0 0 2.25 2.50 *0 0 0 0 0 0 2.50 2.70 Excellent 0 0 0 0 0 0 Total 40 3 43 0 0 0 * Survey conditions were excellent, however only about 30% of the reach was visible due to access. 11 Figure 1. Map of Knutson Creek with proposed hydro-project identified, and Pedro Bay Village, and Pedro Pond P1 shown (Map Courtesy of Polarconsult Alaska). 12 Figure 2. Map of upper Knutson Creek from approximately RM 1.2 to RM 2.8 with fish trap sites and proposed hydro-project location identified (Map Courtesy of Polarconsult Alaska). 13 Figure 3.Typical trap catch of “small” but abundant Dolly Varden in upper Knutson Cr., trap #6, 8/23/12. Figure 4. Mature male and female Dolly Varden, upper Knutson Creek, 8/23/2012. 14 Figure 5. Sockeye salmon spawning in upper Knutson Creek at trap site 2, 8/23/12. Figure 6. Sockeye salmon carcass (bear killed), upper Knutson Creek, 8/23/12. 15 Figure 7. Knutson Cr. tributary ‘R1’, Trap site T-1 (left of Vern Jensen, Pedro Bay resident), 50 yds. above Knutson Cr. confluence and approx. 90 yds below proposed powerhouse site, 8/23/12. Figure 8. Upper Knutson Creek, approx. 50yds below lower flow gage site, 8/25/12. 16 Figure 9. Upper Knutson Creek, downstream view, trap site #8, 200m above proposed intake, 8/23/12. Figure 10. Sockeye salmon spawning in the upper end of Pedro Bay Pond P1, 8/25/12.