Water Stewardship Information Sources
| Citation | Ecofish Research Ltd. 2008. Puntledge River Water Use Plan, Steelhead Production: Puntledge River Steelhead Production Monitoring Study 2007. Prepared for BC Hydro. |
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| Organization | BC Hydro |
| URL | https://www.bchydro.com/content/dam/hydro/medialib/internet/documents/environment/pdf/wup_puntledge_river_steelhead_production_monitoring_stud1.pdf |
| Abstract/Description or Keywords | The Puntledge River Water Use Plan (WUP) was prepared over a two-year long consultative process where stakeholders collaborated to identify the key effects of the operations of BC Hydro’s Puntledge River Project (BC Hydro 2003). The primary objective of the steelhead production monitoring program is to reduce uncertainty related to the benefits of the minimum flow to production in Reach C of the Puntledge River while the secondary objective is to examine the effects of kayak pulse flows on juvenile steelhead in Reach C. To address these objectives adult and juvenile fish inventories were conducted. Adult surveys were conducted largely by means of snorkel swims (i.e., live counts) in pre-selected snorkel sections. Adult surveys were conducted throughout the late winter/early spring (January through to April) and summer seasons (July through August). During the winter swims in lower reach C, seven adult steelhead (2 wild (1 female, 1 undetermined), 1 hatchery (male), and 4 unknown (1 male, 2 female, and 1 undetermined)) were observed on January 31, eight adult steelhead (3 wild (1 female, 1 male, 1 undetermined), 1 hatchery (female), 4 unknown (3 females, 1 male)) were observed on March 2, and seven adult steelhead (6 wild, 1 unknown; 4 females, 3 undetermined) were observed on April 4, 2007. The focal species during the summer swims in upper and lower Reach C on July 10, 16, 27 and August 15, 2007 were summer steelhead and chinook. Adult summer-run steelhead were only observed on July 16 in lower Reach C, when two were observed. In upper Reach C counts of chinook varied from 47 on July 10 to 98 on July 27. Compared to upper Reach C, chinook counts in lower Reach C were much higher ranging from 106 on July 16 to 174 on August 15. Additional information on adult migration was also obtained from underwater video monitoring conducted at the Puntledge River Fishway. Video monitoring was conducted during three time periods at the Puntledge River Fishway between March 1 and May 1, 2007. During these monitoring periods, a total of 14 steelhead were observed. The first steelhead was observed on March 17, 2007 during the third observation period (March 15 to May 1, 2007) and the last steelhead was observed on April 30, 2007. After the final snorkel swim conducted on April 4, 2007, 7 steelhead were observed. Comparisons between video and snorkel observations are difficult because of the incomplete video record. Fry (0+ ) recruitment was quantified at ten sites using electrofishing methodologies, following the multiple-pass removal/depletion process. General and detailed physical habitat parameters were also collected at all juvenile inventory sites. To compare the observed fry densities at the electrofishing sites against the predicted potential maximum fry (0+ ) densities a log-log scatter plot (Allen Plot) of observed density versus size at age for steelhead was compared against predicted maximum densities based on total alkalinity. The predicted maximum densities were calculated from a model developed by Ptolemy (2005) with inputs of total alkalinity and average mean weight by size class. The mean base flow alkalinity in the Puntledge River in 2007 was 18.7 g/ml (n = 10 samples), suggesting that the river can sustain a maximum of 246.8 g (per species and age class) per 100 m2 of suitable habitat. Adjusted fry (0+ ) densities at individual sites varied from 0.0 to 34.4 fry/100 m2 (adjusted biomass ranged from 0.0 to 110.2 g fry/100 m2 ). The geometric mean adjusted density for all sites combined was 5.9 fry/100 m2 . Predicted maximum densities among sites where fry were captured (n = 9) varied from 51.4 to 85.1 fry/100 m2 (predicted maximum biomass was 246.8 g/100 m2 ). At all sites adjusted fry densities were below maximum densities predicted by the Ptolemy (2005) model. The 2007 Puntledge fry density data was compared to data from Griffith (1995), BCCF (1998, 1999) and from previous years of this study (2006; Ecofish Research Ltd. 2007). In 2007, the adjusted densities ranged from 0.0 to 44.6% that of the theoretical maximum (n = 10, mean = 15.7%, S.D. = 13.2%). This compares to a range of 0.0 to 41.6% in 1995 (Griffith 1996), 0.0 to 87.5% in 1998 (BCCF unpublished data), and 7.2 to 59.3% in 1999 (BCCF unpublished data) and 0.0 to 85.0% or 0.0 to 53.5% in 2006 (using the Ptolemy 1993, and Ptolemy 2005 models, respectively). The lowest geometric mean density was observed in 1995 (2.2 fry/100 m2 ), followed by 2007 (5.9 fry/100 m2 ), 1998 (6.4 fry/100 m2 ), 2006 (11.3 fry/100 m2 ), and 1999 (16.0 fry/100 m2 ). To put the adjusted fry density data from the Puntledge River in a regional context, the geometric mean fry densities from 1995 to 2006 in the Little Qualicum River, Tsable River, Trent River, Oyster River, Quinsam River, and Salmon River were plotted along with the data from the Puntledge River. The geometric mean fry density for all years in all rivers (excluding the Puntledge River) combined is 24.4 fry/100 m2 . Geometric mean fry densities in the Puntledge River were lower than in other rivers, except for the Oyster River in one year. The lowest density in any river was observed in the Puntledge River in 1995 (2.2 fry/100 m2 ). Parr (≥1+ ) recruitment was quantified by means of snorkel surveys at six pre-selected index sites. Snorkel counts were the primary means of parr enumeration. In 2007, all parr snorkel counts were conducted during the night. On September 24 – 26, 2007, the density of steelhead parr (≥1+ ) at the six sites ranged from 0.8 to 11.4 parr /100 m2 (n = 6, mean = 5.4 parr /100 m2 , S.D. = 4.4 parr /100 m2 ). In addition to steelhead fry and parr, coho and chinook salmon fry and parr were also observed. In 2007, the kayaking pulse flows took place between May 27 and May 28. Sites with high potential for stranding were examined prior to the pulse flow releases. In 2007, monitoring for stranding was carried out at previously identified potential stranding sites: Sites 3-B, 4-A, 4-C, 4- D, 7-D1 and 7-D2 (previously designated as Site 3, Site 4, Site 4, Site 4, Site 8 and Site 8, respectively). In addition to these sampling sites, ten additional areas (supplemental sites) of potential stranding were examined for stranded fish. Fish stranding was observed at two of six sites. The greatest number of fish stranded (and relocated) was observed at Site 3-B (n = 24, all of which were coho fry). Five coho fry were also salvaged from Site 7-D1. No stranded fish were observed at Sites 4-A, 4-C, 4-D or 7-D2. All stranded fish were found alive in isolated pools. In the supplemental sites fish stranding was observed at four of ten sites. Site 5-B had the greatest number of stranded fish (n = 16: 12 coho fry, 3 chum fry, and 1 pacific lamprey). At Puntledge Park one dead coho fry was found, and this was likely a result of stranding. At Site 3-B, 14 stranded coho fry were salvaged from two small pools and a secondary channel located behind Site 3-B. At Site 7-A2 one stranded coho smolt was captured in a small isolated pool. At Site 4-B one dead coho fry was found; however, this mortality was not likely a result of stranding as fungus was present on this fish. This is the second year of the Puntledge River steelhead production monitoring study and the results collected to date are not sufficient to allow recommendations to be made regarding flow regimes in the Puntledge River. However, we are able to make some recommendations regarding the methodologies employed this year to improve the performance next year: 1. Ecofish will attempt to continue maintaining consistency in crew staffing by allocating the same experienced staff to the same field tasks within and among years, where practical. Ecofish has secured additional experienced staff for this work: all Ecofish personnel will have sufficient experience and training to complete the planned work. 2. Under the 2007 budget constraints, it was impossible to conduct opportunistic electrofishing to increase the parr (>1+ ) sample size for ageing purposes. It may be possible to collect additional samples during 2008. Discussions will be undertaken with BCH to determine the need for additional sampling. |
| Information Type | report |
| Regional Watershed | Vancouver Island North |
| Sub-watershed if known | Puntledge River |
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| Project status | complete |
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