Wahleach Project Water Use Plan Lower Jones Creek ... - BC Hydro

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were completed for pink salmon during the spawning channel operation, recent site specific survey life is not available for either chum or pink in Lower Jones Creek. The values used for survey life (r) are based on available information from the literature. A maximum survey life value for both chum and pink salmon was applied to a model developed by Korman et al. (2002) (Equation 2) which results in a decaying survey life value as the spawning period progresses. With this model each day within the spawning period is given a specific survey life and the day-specific survey life is applied to the total count on the corresponding day. Equation 2. Daily survey life calculation � � � max� � �� ri � r 1� r r � half �c t � i � � rhalf �c rhalf �c � � t half i �� Where: c = modified slope constant r max = maximum survey life possible t half = the day at which the survey life is half the maximum t l = day of the run The maximum survey life ( r max) is determined using the mean r calculated by Perrin and Irvine (1990), for salmon spawning in the Georgia Straight Region. The maximum survey life selected for both chum and pink salmon was 18 days. The day at which the survey life is half of the maximum value ( t half) was defined as the date at which the sum of the peak live plus dead count was greatest. The rate of change of the survey life or slope of the survey life curve (c = 1.25 for pink, c = 1.0 for chum) has been used in previous studies and was tailored to ensure a reasonable minimum survey life ( r min) as defined by the literature. Uncertainty regarding survey life is assumed to be normally distributed around the assessed value, with a standard deviation assessed in Perrin and Irvine (1990) and outlined in Table 1. The normally distributed error for survey life eri is then calculated as: Equation 3. Survey life estimate error calculation Er = 1.96 √ V(r) Table 1 Survey-life calculation constants applied to escapement calculations Species rmax V(r) c Chum 18 0.42 1.25 Pink 18 0.44 1.00 where: rmax = maximum estimated survey life V(r)= Variance (r) c = modified slope constant The WUP monitoring TOR also describes a visibility/observer efficiency error calculation. Lower Jones Creek Fish Productivity Monitoring 2008-2009 6
Visibility is often different between surveys and by calculating the difference in visibility between adjacent surveys the effects of extrapolating errors in visibility for the unsurveyed period between surveys can be assessed. The error in visibility (ev) is then calculated as follows: Equation 4. Observer efficiency estimate error calculation ev = 1.96 √ V(dV) Where: V(dV) = the standard deviation of the absolute value of the differences of observer efficiency between adjacent surveys. The 95 % confidence limit for the escapement estimate is calculated by substituting vi with vi +/- ev and ri with ri +/- Er into Equation 1 simultaneously. We have modified the terms of reference slightly to include confidence limits using the calculation described above as well as using only the survey life error since the observer efficiency error calculation often results in the substitution of unreasonable observer efficiencies. That is, observer efficiencies resulting from the error calculation are often well above one or near zero. An estimate of escapement was not provided for coho salmon due to the very low numbers observed. Also, coho salmon spawn primarily in areas of Lorenzetta Creek outside of the defined survey limits of Section 5. Although surveyed a number of times this year, Lorenzetta Creek is not routinely covered during the ground surveys. We provide daily counts and carcass recovery information. 3.3 Channel Morphology and Spawner Density Wetted area for each section was estimated by measuring wetted width at a number of locations within each section and multiplying the average width by the length of the section. Since Lower Jones Creek is very prone to channel shifting the wetted area assessment was completed four times during and after the peak spawning period. The initial assessment was completed near the beginning of the spawning period and the following assessments were completed after significant flow events to determine their effect on channel morphology. An assessment of spawning habitat within each section was also provided. Spawner density was calculated for each section by applying the percent distribution of total live counts for each section to the estimate of total escapement for each species. This was considered a better approach than calculating escapement estimates for each section due to the uncertainty in fish movement during the spawning period. The wetted area and transect measurements taken throughout the season were compared to determine whether or not the channel was shifting or changing significantly during the spawning period. Photo documentation was also provided to demonstrate any significant changes in channel morphology. Shifting channels will potentially impact egg-to-fry survival if they occur during the spawning or incubation periods. Other environmental information collected during each of the surveys included: Lower Jones Creek Fish Productivity Monitoring 2008-2009 7
Page 1 and 2: Wahleach Project Water Use Plan Low
Page 3 and 4: Executive Summary As required by th
Page 5 and 6: List of Figures Figure 1 Lower Jone
Page 7 and 8: 1. Introduction The Wahleach Water
Page 9 and 10: Figure 1 Lower Jones Creek study lo
Page 11: The crew members were on opposite s
Page 15 and 16: equired for a mark and recapture. A
Page 17 and 18: 140 120 100 80 60 40 20 0 Chum Adul
Page 19 and 20: Table 4 Lower Jones Creek adult chu
Page 21 and 22: Figure 4 The side channel marked in
Page 23 and 24: 16 14 12 10 8 6 4 2 0 01‐Sep 06
Page 25 and 26: In the single trap configuration, t
Page 27 and 28: Lorenzetti Creek), and significant
Page 29 and 30: Temperature (°C) 18 16 14 12 10 8
Page 31 and 32: 5.3 Fry Out-Migration Chum salmon e
Page 33 and 34: in Lorenzetti Creek. The boulder ri
Page 35 and 36: Macnair, Jason C., 2004, 2003 Lower
Page 37: April 16, 2008 Lorenzetti Creek. Lo

Wahleach Project Water Use Plan Lower Jones Creek ... - BC Hydro

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