2017 Chilliwack River Chum Escapement Enumeration
Continuance of 2016 Pilot Project – 2017 (2 nd Year) GOAL: to enumerate total Fraser River Chum Salmon escapement by combining a high precision estimate of Chilliwack River Chum escapement with the GSI ratio of Chilliwack Chum to the total Fraser Chum captured in the Albion Test Fishery
Introduction • BACKGROUND • APPLICATION • STUDY AREA • RECOVERY • ENVT’L CONDITIONS • PRELIM. POPULATION EST.
Study Area This study took place • 50 km within the Chilliwack River watershed ( highlighted below ) Data to be linked to • Albion Test Fishery data ( highlighted below ) Pitt River Stave River Chilliwack Lake CHILLIWACK R. ALBION
Chilliwack River Watershed 2016 Application Area Boundaries 2017 Application Area Boundaries (+ some Upper R. tribs – not shown) Study Area 10 km APPLICATION • In 2016, tags were applied in lower end with hopes to obtain even mark distribution/mixing throughout watershed – RESULT : very few tags recovered in upper river • In 2017, the application crew distributed the tags with roving application; marks applied throughout entire watershed.
Recovery Area Boundaries Chilliwack River Watershed + many other Upper R tribs (not shown) Study Area 10 km RECOVERY • Utilized same recovery areas as 2016 field season • Mainstem: Hatchery to KW Bridge • Lower Tribs: Sweltzer, Peach, Hopedale, Street, Giesbrecht • Upper Tribs: Centennial, Middle • And added many new recovery areas to 2017 field season • Lower Tribs: Salewin, Anderson, Borden, Wingfield • Upper Tribs: Anglewing, 15 Mile, 14 Mile, Centre, Foley
Environmental Issues • Rain / High Water
Environmental Issues Historical Mean 1950-2016 Water Level 2016 Water Level 2017 3.5 2 periods of very high water levels 3.3 3.0 Station 08MH001 Water Levels (m) 2.8 2.5 2.3 2.0 1.8 1.5 Extended period of lower than avg. water levels 1.3 (during peak migration) 1.0
APPLICATION
APPLICATION Sec. Mark - Double Peterson (new to 2017) POH Length Data (cm) Other Metrics Recorded at Application: Tag Site Location • Daily Set # • Better application gear (nets new to 2017) Rel Tag Time • Maturity Code (A, B, C) • Marks (SP, H, N, F, W) • Stress Rel Code (1, 2, 3, 4) •
APPLICATION
APPLICATION 160 140 Male Female 120 100 80 60 40 20 0 Tag Type: Double Peterson Disc • Application Period: 12 Oct – 01 Dec (31 Application Days) • Total Tags Applied: 1826 (1120 Male; 701 Female; 5 Sex NR) • Untagged CM Rel.: 383 (187 Male; 196 Female) •
RECOVERY
1000 1200 1400 200 400 600 800 100 120 20 40 60 80 0 0 • • • • 11-Oct 9 Total Untagged Rec 13-Oct 3 Tagged Rec TOTAL RECOVERIES: 14,499 Total Tagged Rec: Total Untagged Rec: 13,975 (7,215 Male; 6,748 Female; 12 Sex NK) Recovery Period: 15-Oct 37 4 1 17-Oct 10 4 19-Oct 1 21-Oct 27 23-Oct 2 6 1 9 25-Oct 1 16 15 27-Oct 1 29-Oct 133 1 31-Oct 1075 107 RECOVERY 39 2 193 02-Nov 2 268 5 04-Nov 524 (293 Male; 225 Female; 6 Sex NK) 12 Oct – 21 Dec (complete overlap w/ App.) 06-Nov 411 15 70 1 40 08-Nov 998 50 597 10-Nov 33 12-Nov 261 25 701 14-Nov 19 206 1 652 16-Nov 38 599 34 18-Nov 20-Nov 285 8 1019 84 903 22-Nov 3 18 24-Nov 26-Nov 186 5 28-Nov 500 14 428 1 536 30-Nov 7 180 1 02-Dec 04-Dec 313 4 563 9 06-Dec 1229 27 165 1 98 08-Dec 10-Dec 138 1 12-Dec 249 3 307 8 326 14-Dec 1 16-Dec 110 18-Dec 1 39 2 20-Dec 1 3
RECOVERY AVG TAG INCIDENCE TOTAL REC TAG INCIDENCE 2500 10.0% TRIBUTARIES MAINSTEM SECTIONS 9.0% 2000 8.0% 7.0% 1500 6.0% 5.0% 1000 4.0% 3.0% 500 2.0% 1.0% 0 0.0% DOWNSTREAM UPSTREAM Higher tag incidence in lower watershed in Increased tag incidenc in upper watershed in 2017 as high number of tags applied here 2017 – due to new roving application strategy during low water
RECOVERY BIOSAMPLING Total Bio Sampled: 712 (388 Male; 316 Female; 6 sex NK) • Total Scale Samples: 658 (357 Male; 298 Female; 3 sex NK) • Average Length: 58.8cm (Male 60.0cm; Female 58.3cm) • Proportionate Length Comparison 16% Male Female 14% Proportion of Total Sampled 12% 10% 8% 6% 4% 2% 0% 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 Length (POHL-cm)
RECOVERY
M (total marks applied) = 1,826 C (total carcasses rec) = 14,499 R (total marks rec) = 524 N = (1,826 x 14,499) 524 N = 26,475,174 50,525 524 Prelim. Population Estimate N = MC R
2017 CREW
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