550 likes | 557 Views
This article provides an overview of the wild steelhead stock status in British Columbia, including population details, stock abundance estimates, release data, and assessment methods. It also highlights specific rivers and locations where steelhead escapements have been observed.
E N D
Wild Steelhead Stock S t a t u s . . . BC 2006
British Columbia in Perspective • 1200 km (720 mi) south to north • 500-1000 km (300 – 600 mi) wide • 950,000 sq km (367,000 sq mi) • 75% mountains; 60% forested; 10% farmland and lakes; <2% rivers • 7000 km (4200 mi) of coastline
Population Details • ~4.0Million total • ~ 60% Vancouver • ~16% Vancouver Island • ~24 % elsewhere but only 4% in northern half • <4% Aboriginal • Most of BC’s steelhead staff are in this room
B C (Wild) Steelhead Facts • About 580 steelhead “rivers” (3rd order or larger) • About 630 stocks (85% WSH, 12% ISSH, 3% CSSH) (Ahrens = 401 stocks in 21 CUs) • About 1/3 of rivers along remote mid & N coast (seldom, if ever, fished) • About 1/4 of rivers on Vancouver Island
Number of Streams Stocked with Steelhead Juveniles Originating From Wild Brood Stock (F=fry, S=smolt) Time Island Mainland Thompson Cariboo Skeena All PeriodF SF SF SF SF SFS < 1975 1 3 2 2 0 0 0 0 0 0 3 5 1975–84 11 15 14 8 1 1 2 0 4 1 32 25 1985–94 19 17 18 19 1 1 3 0 8 1 49 38 1995–01 11 10 6 14 1 0 0 0 0 1 18 25 2002-05 850? 8 0 0 0 0 0 1 8 13
Steelhead Releases 1975 - 2001 PeriodAv # FryAv # Smolts 1975-79 .07M .07M 1980-84 1.03M .60M 1985-89 1.59M .91M 1990-94 .73M .82M 1995-99 .26M .63M 2000-05 .09M .60M
Stock Assessment Methods • Total Counts • Weirs/resistivity counters (Keogh, Deadman, Sustut, Kitwanga, Kloiya) • Indices of Abundance • Gillnet test fisheries (Fraser, Skeena) • Fishwheels (Nass) • Snorkel observations (some total counts) • Aerial Counts (Chilko) • Juvenile sampling
Nass Lake Bell-Irving River Damdochax Creek Bowser Lake Meziadin Lake BC Kwinageese River N White River Nass River Tchitin River 50 km Cranberry River Canyon City (Gitwinksihlkw) Grease Harbour New Aiyansh Kiteen River Kincolith River Kincolith Tseax River Greenville (Lakalzap) Ishkeenickh River Nass River Watershed
Fishwheel Locations Nass River Meziadin Lake Kwinageese River White River N Tchitin River Grease Harbour Cranberry River Canyon City (Gitwinksihlkw) 50 km New Aiyansh Kiteen River Kincolith River Tseax River Kincolith Greenville (Lakalzap) Ishkeenickh River
Nass River Fishwheels • 6 wheels operated annually • Mainly for stock assessment • Late May to late September • Now operated as the sole in-season salmon indicator for the Nass
PrinceRupert BC Digby Kaien Khyex Island Island River Tyee Test Port Edward Skeena River Fishery Chatham Smith Island Sound N Ecstall Porcher River Kennedy Island 0 6 km Island Tyee Test Fishery Location
Khyex River Khyex Bank SKEENA RIVER Highway 16 Lookout Bank Tyee Tyee Test Fishing Site Port Essignton Ecstall River Tyee Test Fishing Site
Moosevale Weir Location Creek Two Lake Creek Johanson Creek Johanson Sustut Lake Lake Birdflat Creek Red Creek Skeena River Asitka River Sustut River Bear River Study Area N Bear Lake Scale: Approximately 1:340,000 Upper Sustut River Watershed
Trends in Bonaparte Fishway Opened
Note to Bob, recall that these are not reconstructed returns, these are simply the observed spawner returns divided by the predominant brood year abundance.
Keogh River Steelhead Smolt counts, 1977 to 2005 • The capacity for smolts dropped from 7,000 (>10,000 with nutrient addition) to <2000 after 1993. • recent increases in smolts can be attributed to WRP. Extreme low flows in 2004 hindered exit for all species.
Smolt-to-adult survival trends SAS has dropped from average of 15% to <4% Like wild coho, SAS increased in ‘97 and ‘98, but recently declined based on returns thus far of 2001 smolts 2003 estimate based on partial returns.
Steelhead smolt yield and adult returns at the Keogh River, B.C.