Proposed Lower Fraser River Recreational Hook and Release Sockeye Mortality Study. FRAFS Technical Meeting, Prince George, June 18, 2008

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1 Proposed Lower Fraser River Recreational Hook and Release Sockeye Mortality Study FRAFS Technical Meeting, Prince George, June 18, 2008

2 Background There are no mortality studies for sockeye caught and released in fresh water using recreational gear. In recent years, the Department has been using a 10% mortality rate to sockeye released in freshwater. Due to the nature of bottom bouncing the majority of sockeye caught with this method are primarily hooked on the outside of the mouth or head. The location and degree of hooking injuries suggests that mortality rates should be low but it needs to be quantified. 2

3 Introduction In 2007, the Cheam Band submitted a proposal to the Fraser Salmon & Watershed Program (FS&WP) to conduct a recreational hook and release sockeye mortality study. The study was not conducted. In 2008, the FS&WP is leading the development of a comprehensive study design to estimate short-term release mortality on sockeye caught and released in the lower Fraser River recreational fishery. To be successful, the study design team will work with First Nations, recreational anglers and Departmental employees to ensure agreement on study design, goals and implementation. 3

4 Study Design Team Project Biologist Jim Thomas of J.O Thomas & Associates FRAFS, Pete Nicklin FS&WP, Andrew Stegemann DFO Stock Assessment, Sue Grant, Richard Bailey, Jason Mahoney DFO Resource Management, Debra Sneddon DFO Science, David Patterson 4

5 Objectives Primary objective is to estimate the short-term (24 hour) mortality of recreational catch & release practices that commonly occur in Fraser River recreational salmon fisheries. Secondary objective is to assess the influence of selected variables on hooking mortality rates. 5

6 Methodology Sockeye will be caught by anglers using a range of gear and angler experience. Handling methods will be representative of catch and release practices common during recreational fisheries. A control group must be included to estimate mortality. Controls are used to account for effects of fish transport, handling and holding in net pens. 6

7 Limitations The average sockeye cycle is 4 years. To account for inter-annual variability in migration conditions, fish conditions, fish abundance and stock composition, it is recommended this study be conducted over a four year period. The results from any one year will provide some limited information for use in fisheries management decisions. 7

8 Limitations, con t Single year study has limited value Conducted on one bar No open recreational fishery Only a 24 hour holding study 8

9 Location and Impacts Study area is proposed to be Grassy Bar, just downstream of Island 22 Park. It is estimated that approximately 1,200 sockeye encounters are required to adequately assess the impacts. It is estimated that a maximum of 120 sockeye would be sampled. 9

10 Data Collection Data will be collected on: Angler effort Landing information Control group 10

11 Net Pens The study will use net pens to hold the fish for 24 hours. The net pens will be located near the fishing site to minimize transport time and related fish stress. Information will be collected hourly on flow, temperature (water & air), dissolved oxygen and depth. 11

12 Net Pens con t. The primary holding pen will be placed in an anchored predator net pen. The pens will be covered and locked to ensure sockeye cannot get out. To alleviate concerns of vandalism, theft and liability the pen site will be provided with round the clock security. 12

13 Sampling Physiological sampling (3 types) Non-invasive sampling Fish are placed in a V-trough, where they are held with minimal restraint and allowed freshwater to the mouth and gills. Invasive sampling A limited sample of fish that survive the 24 hour holding will be killed and sampled. Osmotic and ionic regulation 13

14 Next Steps Consultations FWJTC & FRAFS Bi-lateral First Nations Local Sport Fish Advisory Committees Budgets/funding Complete budgets and find funding Participant involvement Beach seine participants Volunteer anglers Fisheries technicians 14

15 Questions and Comments If you have any questions or comments please contact: Debra Sneddon Phone Mail: Annacis Parkway, Delta, BC V3M 6A2 15