73078

2008-311-00 EXP NATURAL PRODUCTION MGMT & MONITORING

7/1/2016

6/30/2017

157. Collect/Generate/Validate Field and Lab Data

Work Element Usage Report

N: 157 - Spring Chinook & Steelhead: Operate Resistance Board Weir in Shitike Creek

The weir was designed to operate year-round to capture fish traveling up and downstream. The RBW will actively capture all fish from the beginning of the steelhead upstream migration (approximately mid December) until daily maximum temperature reaches 17 °C. Once daily maximum water temperatures are 17 °C (usually by late May), passive movement through the weir will be enumerated by video observation. Video monitoring will continue until steelhead upstream migration resumes the following year. During the active capture period, the weir will be checked a minimum of once daily and increase depending on the number of fish present in the trap box.

The total population of migrating steelhead will be obtained by summing daily counts of fish captured at the weir. Biological information will be collected on all captured (handled) fish, including date of capture, sex, origin (hatchery or wild), length (nearest cm), weight (nearest kg), whether the fish is pre-or post- spawned (if determinable) and direction of migration (upstream or downstream). Scale samples will be taken from all fish to be archived for potential analysis later. All fish will be checked for external marks and scanned for the presence of a PIT or CWT and reported to regional databases. All adult steelhead captured in the upstream box with receive a PIT tag and secondary external mark (e.g., an opercle punch or a floy tag) before being passed upstream, as a method of determining weir efficiency. Because the number of steelhead migrating upstream is variable and relatively small (<100), a calculation of efficiency is not likely possible. In order for a mark-recapture estimate, a minimum of 100 steelhead will be marked with at least a 20% recapture rate and target a precision no more than 30%.

Recaptures will be recorded during spawning surveys or as post-spawn migrants captured in the downstream weir box. Surveyors will examine carcasses observed during spawning surveys for marks and/or PIT tags. Downstream migrating steelhead will be examined for marks and scanned for PIT tags before release downstream. If less than 100% of these recaptured fish (carcass + downstream migrants) are marked, a mark/recapture methodology will be utilized (if sufficient numbers return) to estimate the total spawning escapement of steelhead.

A resistance-board weir (RBW) was installed in Shitike Creek at RKm 2 in January 2015. The weir was removed from this site in the summer of 2015 because of hydraulic issues, and was relocated to a different site (Rkm 1.5) in May of 2016. The installation of the RBW is semi permanent as there are up to 10 floating panels with a permanent attachment point on the streambed, allowing panels to pivot so debris passes. There are removable picket sections on either side of the floating panels, and removable trap boxes. The RBW will be fished year-round, although the traps will be run with video only during the summer when water temperatures become too warm to capture and handle fish.

$31,367

8.01%

07/01/2016

06/30/2017

06/30/2017

Concluded

n/a

n/a

Recurring