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

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Figure 2. Lower Jones Creek Fry trapping locations and adult survey sections 3. Methods 3.1 Adult Enumeration BCH Rearing Channel Ground surveys were undertaken by a crew of two people walking in an upstream direction. The survey was started at the Fraser River confluence and extended up to the barrier to fish migration. Lower Jones Creek was divided into 4 sections (Figure 2) and counts were maintained separately for each section. The four survey sections are: � Section 1: Fraser River confluence to Lorenzetta Confluence (80m) � Section 2: Lorenzetta confluence to boulder riffle (110m) � Section 3: Boulder riffle to hydrometric station (655m) � Section 4: Hydrometric station to barrier (180m) BCH Spawning Platforms The lower section Lorenzetta Creek, from its confluence with Lower Jones Creek to the DFO spawning platform approximately 190 m upstream (Section 5) was also surveyed. Lower Jones Creek Fish Productivity Monitoring 2008-2009 4
The crew members were on opposite sides of the creek and remained in continuous communication with each other to ensure as many fish as possible were observed and to avoid duplicate counts of individual fish. Fish were identified to species and live fish were counted as either holding or actively spawning. Carcasses were identified to species, enumerated and above the high water mark to avoid counting more than once. Counts were conducted once or twice weekly from September 9, 2008 to December 22, 2008. An observer efficiency was estimated for each of the ground surveys. The observer efficiency is a qualitative assessment based on flow conditions and water clarity and provides an estimated efficiency for the days count. For example, an observer efficiency of 75% estimates that 75 % of the fish present on that day are counted and the count is expanded by that fraction in the AUC method. An extended section of Lorenzetta Creek (approximately 600m upstream of the Laidlaw/Lorenzetta bridge) was surveyed periodically during the coho migration and spawning period. This was to better estimate the actual number of coho migrating through Lower Jones Creek and to determine the total distribution of this coho population. 3.2 Escapement Estimates The analytical procedure to provide estimates of total escapement from the day-specific counts is defined in the Wahleach Water Use Plan Monitoring Terms of Reference document and has been approved by fisheries representatives during the TOR development phase of the WUP implementation process. The procedure is summarized below. An area-under-the-curve trapezoidal approximation analysis was applied to the day specific counts to provide an estimate of escapement for chum and pink salmon to Lower Jones Creek. This method is a modification of the area-under-the-curve method commonly applied to these types of survey results and is shown below (Equation 1). Equation 1 Area-under-the-curve trapezoidal approximation method (Hilborn et. al. 1999) � � �x* i x i � 1� ti � ti � 1 n 1 � x * 1 x * n � * � N j � � � � � � 2 � r1 v1 rnvn i� 2 rivi � where: N = total population estimate i = survey number (first survey date i=1) n = total number of surveys t = survey date r = survey-life of adult spawner v = visibility x* = total count of adults observed for each survey number i and section j Perrin and Irvine (1990) and Schwarz and Manke (2000) concluded that survey life of adult spawners cannot be extrapolated between years or species on the same stream without introducing serious errors in escapement. To quote Perrin and Irvine (1990) “Survey life (residence time) should be determined on a site-specific basis each time the AUC method is used to estimate escapement”. Although some survey life assessment Lower Jones Creek Fish Productivity Monitoring 2008-2009 5
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: Figure 1 Lower Jones Creek study lo
Page 13 and 14: Visibility is often different betwe
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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