July 9, SINTEF Fisheries and Aquaculture 1

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1 Exploring the influence of climate, competition and aquaculture on the dynamics of Fraser River sockeye salmon and the economics of their fisheries Yajie Liu, SINTEF Fisheries and Aquaculture, Norway Brendan Connors ESSA Technologies Ltd, Canada July 9, 2014 SINTEF Fisheries and Aquaculture 1

2 Outline Research problem Methodological framework Results Discussion Limitations SINTEF Fisheries and Aquaculture 2

3 Fraser River sockeye salmon - Ecological, social and economic importance spawning locations - 18 stocks SINTEF Fisheries and Aquaculture 3

4 Run timing Fishery management groups based on run timing for which target escapement Fisheries managed and exploitation by 4 composite rates stock are set groups Summer Late Abundance Early Stuart Early Summer June September SINTEF Fisheries and Aquaculture 4

5 Harvest USA First Nation (food, culture & ceremony) Recreational fishing First Nation (econ. Opportunity) Commercial fishing SINTEF Fisheries and Aquaculture 5

6 log e (recruits/spawner) The problem 16 recruits/spawner recruit/spawner SINTEF Fisheries and Aquaculture 6 Brood year

7 Causes Ocean conditions - SST Prey competition Pink salmon Aquaculture pathogens (?) SINTEF Fisheries and Aquaculture 7

8 SST anomaly ( O C) SST Pink anomaly (100s millions) 5 6 Pink salmon abundance (millions) ECVI WCVI CC ECVI WCVI CC SST anomaly Year Year Year SINTEF Fisheries and Aquaculture 8

9 Farm production (1000s t) Production (1000 t) Salmon farm tenure ECVI WCVI CC Fraser Year SINTEF Fisheries and Aquaculture

10 SINTEF Fisheries and Aquaculture 10

11 Marine Freshwater ( ) Competition Adult Eggs Sub adult Fry Pathogens (?) ( ) Smolt Oceanographic conditions SINTEF Fisheries and Aquaculture

12 Objectives Explore potential future influence of climate, competition and aquaculture on sockeye salmon in Fraser River; Examine the economic consequences of these stressors; SINTEF Fisheries and Aquaculture

13 Model framework US FN, recreational Catch & effort by comm. fishery Population dynamics Aquaculture Competitors Climate Mgmt. group Pre-spawn mortality Harvest control rule Stock-recruit model catch Cost Profit Troll Seine Gillnet Price SINTEF Fisheries and Aquaculture

14 Model framework 1) Built a salmon population model to generate future spawner-recruit time series with added environmental and anthropogenic factors; æ log e ç è 2) Estimated the potential influence of region-wide shared responses to SST, pink salmon abundance and aquaculture by fitting a modified hierarchical mixed-effects; æ log e ç è R i,t S i,t R i,t S i,t ö ø = a + b S + b S + b S + b S +di, E +e i i i,t 1,i i,t 2,i i,t 3,i i,t j i, j,t+x i,t ö ø = (m +a )+ b S +(m +d )E +e a i i i,t j i, j i, j,t+x i,t 3) Estimated catch and effort log e (E i,t ) = f + log e(y i,t )-qt -g log e (R t )+d i b 4) Measured profit P i,t = (r i Y i,t -(E i,t w i )-l i )(1-u) SINTEF Fisheries and Aquaculture

15 Simulation Scenarios Factor Scenario Description Climate (represented by SST at the ocean entry point in the winter preceding marine entry) Competition (represented by the abundance of potential North Pacific pink salmon competitors in the second year of marine life) Aquaculture (represented by farmed-salmon production along sockeye early marine migration routes) Status quo Increasing Decreasing Status quo Increasing Decreasing None Status quo Increasing Decreasing average SST and interannual variability. SST under a high emission scenario (a1b_mirocmed). Decline in SST to average average North Pacific pink salmon abundance and interannual variability. Gradual increase to 1.5 x average North Pacific pink salmon abundance and interannual variability. Decline in North Pacific pink salmon abundance and interannual variability to competitors to average. No farmed salmon production along early marine sockeye migration routes average aquaculture production and interannual variability. Increase to two x average aquaculture production by and interannual variability after. Sharp decline SINTEF to Fisheries ~ no aquaculture and Aquaculture production.

16 sst anomaly ( o C ) (a) Scenarios increasing status quo decreasing pink salmon (millions) (b) farmed salmon (000s tons) (c) year SINTEF Fisheries and Aquaculture

17 Harvest rule and catch USA 16.5% First Nation (food, culture & ceremony) 1 Million Harvest rule / mgt adjustment Early Stuart Early Summ er Summ er Late ER floor TAM cap Target escapement Management adjustment log( ) Recreational fishing 5% First Nation (econ. Opportunity) 3.7% Commercial fishing Troll (5%) Seine (46.5%) Gillnet(48.5) SINTEF Fisheries and Aquaculture 17

18 Too ensure target escapement is met and weak stocks are protected escg Target escapement Exploitation rate Harvest control rule run size SINTEF Fisheries and Aquaculture 18

19 pink salmon abundance pink salmon abundance (a) no open net-pen aquaculture (c) declining open net-pen aquaculture sea-surface temperature (b) stable open net-pen aquaculture (d) increasing open net-pen aquaculture Recruitment SINTEF Fisheries and Aquaculture 19 sea-surface temperature Greatest: Low competitors Low SST No aquaculture Lowest: High SST High competitors Increasing aquaculture production Increasing competitors vs. low SST Increasing SST vs. low competitors

20 (a) no open net-pen aquaculture (b) stable open net-pen aquaculture pink salmon abundance Catch (c) declining open net-pen aquaculture (d) increasing open net-pen aquaculture pink salmon abundance sea-surface temperature sea-surface temperature SINTEF Fisheries and Aquaculture 20

21 2 pink salmon abundance pink salmon abundance (a) no open net-pen aquaculture (c) declining open net-pen aquaculture sea-surface temperature (b) stable open net-pen aquaculture (d) increasing open net-pen aquaculture SINTEF Fisheries and Aquaculture sea-surface temperature Profit Greatest: Low competitors Low SST No aquaculture Lowest: High SST High competitors Increasing aquaculture production Increasing competitors vs. low SST Increasing SST vs. low competitors 21

22 pink salmon abundance pink salmon abundance (a) stable open net-pen aquaculture (c) Increasing open net-pen aquaculture sea-surface temperature (b) declining open net-pen aquaculture sea-surface temperature Profit loss i) Greatest profit losses associated with salmon aquaculture when: The ocean was cool and Both an increasing competitors and salmon farms. ii) Impacts on profit: competition > SST > aquaculture SINTEF Fisheries and Aquaculture 22

23 Concluding remarks Greatest impacts on recruitment, catch and profit when: the ocean early in marine life is warm, the number of salmon competitors later in marine life were high and there was increasing open net-pen salmon aquaculture production along juvenile sockeye salmon migration routes. Competition has the strongest impact Implications for policy and management: Wild salmon fisheries Aquaculture industry and its development SINTEF Fisheries and Aquaculture 23

24 Limitations High uncertainties Fixed harvest rules used: Conservation goal: overestimated Social-economic goal: underestimated Fixed costs and prices No discounting Underestimated FN and recreational values As food fish SINTEF Fisheries and Aquaculture 24

25 Empirical estimates of spawner recruitment (Ricker / Larkin) relationships and environmental covariates Draw parameter values from multivariate normal sampling distribution and variance covariance matrix plus residual error Select climate, competition and aquaculture production scenario and set annual values for each variable Predict recruits by brood year based on spawner-recruit function, environmental covariates and residual error; assign recruits to return year based on age structure Apply harvest control rule (with mgmt. adjustment for PSM) by mgmt. group Calculate catch by fishery and number of adults returning to spawn to each population Estimate fishing effort based on run size; calculate revenue, costs and profits for each fishery Repeat for 20 years Repeat for 1000 Monte Carlo trials Calculate median annual recruitment, catch, profits for each scenario for all populations SINTEF Fisheries and Aquaculture 25