GSI Ratio Method for Determining Total Fraser Chum Escapement or - PowerPoint PPT Presentation

GSI Ratio Method for Determining Total Fraser Chum Escapement or Albion-based estimate of total Fraser River Chum Salmon escapement using GSI at Albion and enumeration of Chilliwack River Chum Salmon escapement,

Background • Fraser River Chum are a significant driver for mixed stock Chum fisheries occurring in Johnstone Strait (Canadian Areas 12 & 13) and US Areas 7 & 7A • Fraser River Chum are managed as a single stock • Total Chum Salmon escapement to the Fraser River is not enumerated • Only a portion (approx. 30%) of the ~110 Chum spawning sites are annually surveyed • Looking for new tools to estimate total Fraser escapement

Background • Significant Fraser River contributors, such as Harrison and Stave rivers, are surveyed annually • Other significant contributors have not been enumerated for many years • Chilliwack Chum were assessed and found to be genetically different from the Fraser aggregate • Chilliwack spawners were last assessed in 2001 • On average (years 1953-2001), Chilliwack Chum comprised ~20% of the assessed Chum escapement to the Fraser River (range: 2% - 42%)

Background • To enumerate total Fraser River Chum Salmon escapement by: o combining a high precision estimate of Chilliwack River Chum salmon escapement with o the ratio of Chilliwack Chum to the total Fraser Chum captured in the Albion Test Fishery • The proportion of Chilliwack Chum at Albion will be determined using GSI on tissue from scale samples • Scale samples already collected during the conduct of the test fishery

Background • Accurate escapement estimates are important to all aspects of Fraser River Chum salmon management including: o Annual stock run reconstruction (a PSC Bi-lateral Chum Technical Committee initiative supported by the PSC Southern Panel) o Production outlook o In-season terminal abundance estimates (Albion Chum Model) o Evaluating whether management objectives were met

Background • These assessments will assist the PSC Southern Panel, the Chum Technical Committee and the DFO in pre- and post-season management processes • This methodology has been used successfully to estimate Chinook escapement to the Skeena River in northern BC (CTC 2015)

The Math Chilliwack Catch Chilliwack at Albion Escapement = Total Catch Total Fraser at Albion Escapement

The Math Chilliwack Total Catch X Total Fraser Escapement at Albion = Escapement Chilliwack Catch at Albion

2016 Chilliwack River Chum Escapement Enumeration

Introduction Background • Study Area • Environmental Issues • Application • Recovery •

Background GOAL: to enumerate total Fraser River Chum Salmon escapement by combining a high precision estimate of Chilliwack River Chum escapement with the ratio of Chilliwack Chum to the total Fraser Chum captured in the Albion Test Fishery

Study Area • This study took place within the Chilliwack River watershed ( highlighted below ) • Data to be Pitt River linked to Albion Test Fishery data Stave River Chilliwack Lake ( highlighted ALBION below ) CHILLIWACK RIVER

Study Area Vedder Bridge Chilliwack Hatchery Chilliwack River Watershed APPLICATION MAIN APPLICATION SITES • Low in system (Top of Canal – Vedder Bridge) • Tags applied in Hoogies Lickman lower end to Top of KW canal Bridge ensure even Giesbrecht Teskies distribution/mixing Denim Pool throughout watershed

Study Area RECOVERY Mainstem and side channels Lower River tribs (Keith Wilson Bridge to Hatchery) • Sweltzer Creek • Peach Creek • Hopedale Sl. Lower Chilliwack River Tributaries • Street Creek Upper River tribs • Ryder Creek • Centennial Ch. Vedder Peach Bridge • Middle Creek Creek KW Bridge Hopedale Street Creek Slough Sweltzer Creek

Environmental Issues • RAIN!!! 2016 Chilliwack River Water Levels (m) - taken at Vedder Bridge Crossing 08MH001 3.00 2.80 2.60 2.40 2.20 2.00 1.80 1.60 1.40 1.20 1.00 03-Oct 05-Oct 07-Oct 09-Oct 11-Oct 13-Oct 15-Oct 17-Oct 19-Oct 21-Oct 23-Oct 25-Oct 27-Oct 29-Oct 31-Oct 02-Nov 04-Nov 06-Nov 08-Nov 10-Nov 12-Nov 14-Nov 16-Nov 18-Nov 20-Nov 22-Nov 24-Nov 26-Nov 28-Nov 30-Nov 02-Dec 04-Dec 06-Dec 08-Dec 10-Dec 12-Dec 14-Dec ~ 1.0m to 1.4m ideal for mainstem application • Gravel bars and islands clear and visible • flow ideal

Environmental Issues • RAIN!!! 2016 Chilliwack River Water Levels (m) - taken at Vedder Bridge Crossing 08MH001 3.00 2.80 2.60 2.40 2.20 2.00 1.80 1.60 1.40 1.20 1.00 03-Oct 05-Oct 07-Oct 09-Oct 11-Oct 13-Oct 15-Oct 17-Oct 19-Oct 21-Oct 23-Oct 25-Oct 27-Oct 29-Oct 31-Oct 02-Nov 04-Nov 06-Nov 08-Nov 10-Nov 12-Nov 14-Nov 16-Nov 18-Nov 20-Nov 22-Nov 24-Nov 26-Nov 28-Nov 30-Nov 02-Dec 04-Dec 06-Dec 08-Dec 10-Dec 12-Dec 14-Dec ~ 1.4m to 2.0m mainstem application becomes difficult • Gravel bars/islands start to disappear • flow affects net weight

Environmental Issues • RAIN!!! 2016 Chilliwack River Water Levels (m) - taken at Vedder Bridge Crossing 08MH001 3.00 2.80 2.60 2.40 2.20 2.00 1.80 1.60 1.40 1.20 1.00 03-Oct 05-Oct 07-Oct 09-Oct 11-Oct 13-Oct 15-Oct 17-Oct 19-Oct 21-Oct 23-Oct 25-Oct 27-Oct 29-Oct 31-Oct 02-Nov 04-Nov 06-Nov 08-Nov 10-Nov 12-Nov 14-Nov 16-Nov 18-Nov 20-Nov 22-Nov 24-Nov 26-Nov 28-Nov 30-Nov 02-Dec 04-Dec 06-Dec 08-Dec 10-Dec 12-Dec 14-Dec ~ >2.0m mainstem application very difficult • Gravel bars/islands under water; flow too strong for net • BENEFIT – creation of side channel seam lines!!!

Environmental Issues SNOW & ICE… • Elongated cold front hampered carcass recovery (last 3 weeks) • Chum frozen solid (and to the ground itself) • Unable to collect certain biosamples

Application

APPLICATION Secondary Mark (1L/2L) & DNA Sex & Fork Length Data (cm) Other Metrics Recorded at Application: Tag Site Location • Daily Set # • Maturity Code (A, B, C) • Marks (SP, N, F, W) • Stress Rel Code (1, 2, 3, 4) •

APPLICATION

APPLICATION Tags Applied by Date - Male vs. Female 120 Female Male 100 80 60 40 20 0 03-Oct 05-Oct 07-Oct 09-Oct 11-Oct 13-Oct 15-Oct 17-Oct 19-Oct 21-Oct 23-Oct 25-Oct 27-Oct 29-Oct 31-Oct 02-Nov 04-Nov 06-Nov 08-Nov 10-Nov 12-Nov 14-Nov 16-Nov 18-Nov 20-Nov 22-Nov 24-Nov 26-Nov 28-Nov 30-Nov • Tag Type: Peterson Disc • Application Period: 03 Oct – 29 Nov • Total Tags Applied: 1867 (1078 Male; 798 Female) • Untagged CM Rel.: 481 (204 Male; 277 Female) • No defined peak – CM arrival in pulses coinciding with high water events

RECOVERY

• • • • TOTAL RECOVERIES: Total Tagged Rec: Total Untagged Rec: 44,487 (20,510 Male; 23,977 Female) Recovery Period: 1000 1500 2000 2500 3000 3500 4000 4500 500 10 20 30 40 50 60 0 0 13-Oct 2 5 15-Oct TAGGED RECOVERIES UNTAGGED RECOVERIES 17-Oct 4 1 6 19-Oct 7 11 6 21-Oct 7 2 23-Oct 30 2 25-Oct 224 43 862 51 27-Oct 34 9 78 5 29-Oct RECOVERY 31-Oct 23 958 26 605 02-Nov 3 473 45,051 564 (286 Male; 266 Female; 12 Sex NK) 13 Oct – 19 Dec (47 day overlap w/ Application) 1 296 04-Nov 93 06-Nov 4 561 08-Nov 12 1802 9 865 10-Nov 5 1166 7 914 12-Nov 14-Nov 1122 44 3851 16-Nov 38 2110 21 2330 18-Nov 9 1189 2 534 20-Nov 1505 22-Nov 40 2385 32 3308 24-Nov 8 951 9 2775 26-Nov 28-Nov 1263 58 2905 50 30-Nov 1379 8 1053 1 02-Dec 620 04-Dec 3 1873 11 06-Dec 986 11 1134 2 08-Dec 475 10-Dec 6 12-Dec 1209 1 200 14-Dec 143 75 16-Dec 18-Dec 1 109

RECOVERY 12000 5.00% 10000 4.00% # RECOVERED CHUM CARCASSES TAG INCIDENCE 8000 3.00% 6000 2.00% 4000 1.00% 2000 0 0.00% R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 Higher proportions of tagged recoveries @ main application sites Lower proportions of tagged recoveries in upper segments

RECOVERY BIOSAMPLING • Total Chum Bio Sampled: 914 (452 Male; 450 Female; 12 sex NK) • Total Scale Samples: 779 (385 Male; 394 Female) • Average Length: 56.8cm (Male 57.8cm; Female 55.5cm) 16% Proportionate Length Comparison 14% % MALE % FEMALE Proportion of Total Sampled 12% 10% 8% 6% 4% 2% 0% 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70+ Size (cm)

RECOVERY

Prelim. Population Estimate M (total marks applied) = 1,867 N = M x C R (total marks rec) = 564 R C (total carcasses rec) = 44,487 N = (1,867 x 44,487) 564 N = 83,057,229 564 147,265

2016 CREW

Work to Do • Complete analysis/adjustments of the mark- recapture data • Finalize escapement estimation (by sex and age) • Process GSI tissue from Albion scale samples • Use GSI results to estimate total Fraser River Chum escapement • Evaluate all project elements • Provide report to PSC SF Note: Proponents have applied to the PSC Southern Fund to repeat project in 2017/18