Fraser River Chinook Salmon Iv R West Road C Bowron Lake O Ttonwood R
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DFO Science Pacific Region Stock Status Report D6-11 (1999) D r if tw o o d R i FRASER RIVER WATERSHED ve r Takla Lake Sockeye Salmon Distribution M i dd le R . Trembleur Lake 0 25 50miles Stuart Lake 0 40 80km S tua rt R iver Francois Lake Fraser Lake R iver Nadin a R o . k a h Fraser c e PRINCE N GEORGE W B River il o lo w Chilako R w r . o R n i R (upper) v e iv r e r er Fraser River Chinook Salmon iv R West Road C Bowron Lake ottonwoo d R . Q u QUESNEL e s Mitchell River n e l r River e v i Quesnel Lake R r e v WILLIAMS i C R l LAKE e C hil Horsefly R. a co r ti w n Background n o a r s e t iv e p R r R r m o iv R ilk er e o r . h h iv r C e T e R v v i t i f R R a s o R k m e a . s h d t R a A r T r o N. Barriere . r R u e N ich o Lake m m The Fraser River watershed is the largest Canadian s Mo y Chilko e a S Taseko r Adams Lake er F iv Lakes R Lake Shuswap r. e t C Lake r h er a tc iv p R o le producer of chinook salmon. Most Fraser-origin a c g B S a ri n E d o ge B R . ive R r Kamloops L. Mara Lake r B e ir Anderson iv k LILLOOET e Lake KAMLOOPS R chinook spawn in the middle and upper regions of the n n So n h u o o t Mabel e h Thom s s p Lake L a Seton Cr. p i d L. Shuswap R. J l m o lo R N h o ns o . ic ton e Gates Cr. h o e T St t la V rait R M. Shuswap R. watershed, the most notable exception being the iv A e N r C . O R U r h R. NORTH te S R tlatc a V t i aha Harrison River population in the lower Fraser. Chinook r U v N BEND w E a e i . ld t r Harrison . R o P S o f i t R C t a Lake Hell's G t v C a I R e h l S e e Gate l o . a R h L r h A g . a i i l u a i N s q return to the Fraser throughout the year, with most non- R o Pitt . D . C Lake R Stave on ris VANCOUVER ar HOPE Lake H CHILLIWACK Harrison fish arriving in the lower Fraser between April . Chilliwack R. CANADA MISSION R er d ed and September. Harrison fish enter the lower Fraser V U.S.A. during September to November. Map of Fraser River watershed. Fraser chinook spawn primarily from August to December, and most spawners are 3, 4, or 5 years old. the lower Fraser between July 15 and Sept. 1.; and the Fry emerge the following spring and those that spend fall chinook, mostly originating in the Harrison and one or more years in freshwater are called “stream Chilliwack, enter the lower Fraser after Sept. 1. The type,” while those that rear in freshwater less than geographical and timing complexes overlap. For one year (typically less than 6 months) are “ocean assessment purposes, geographic stock aggregates are type.” Harrison fish are unusual in that they are all grouped according to their timing and life history. white-fleshed (most non-Harrison chinook are pink- fleshed) and migrate as recently emerged fry directly Since the early 1980s, the principal hatcheries to the lower Fraser River and its estuary. enhancing Fraser chinook have been the Chehalis and Chilliwack (lower Fraser), Eagle, Shuswap Falls, Fraser chinook are comprised of a large number of Clearwater, Deadman Creek, and Spius Creek (all populations. For management purposes, they are Thompson) and the Quesnel (mid-Fraser) and Stuart/ divided into 4 major geographical stock complexes, and Narcoslie (upper Fraser). In recent years, the 3 timing groups. The geographical stock strata are: Clearwater, Eagle, Quesnel, and Stuart facilities have upper Fraser (those upstream of Prince George and closed. Some enhancement also occurs at small facilities including Nechako), middle Fraser (downstream of throughout the watershed. Enhancement is thought to Prince George but excluding the Thompson), the have a relatively small effect on the total numbers of Thompson, and the lower Fraser (numerically chinook returning to the Fraser, although the effects dominated by fall-returning Harrison-origin fish). The on certain watersheds, such as the Nicola watershed, timing groups are categorized into 3 seasonal runs. The which is enhanced by the Spius Creek Hatchery, and early or spring run migrates through the lower Fraser the Chilliwack River, which is enhanced by the River before July 15; the summer run migrates through Chilliwack Hatchery, can be significant. December 1999 Pacific Region Fraser River Chinook Salmon The Fishery adequately sampled for CWTs, and are therefore excluded from the recovery strata. Under the 1985 Pacific Salmon Treaty, Canada and the U.S. committed to halting the decline of Spring-Run Chinook chinook escapements. Catch ceilings were established for major chinook fisheries from Recoveries of upper Fraser spring-run chinook Alaska to British Columbia and various time and were rare considering the numbers of CWTs area closures were implemented. Since 1994, applied, and these tags were recovered in all strata additional fishery management changes have been (Fig. 1). Most tags were from the WCVI/Entry made to increase the size of spawning stocks of area. Early returning chinook to the upper Fraser upper Fraser River and other chinook stocks. are rarely available to coastal fisheries during July, These have included reduced catch ceilings for but are available to entrance and recreational the troll fisheries, and increased minimum size fisheries in May and June during their return limits and reduced bag limits for the recreational migrations. fishery. In 1997 and 1998, Canadian ocean 0.6 fisheries were dramatically reduced to lessen 0.5 impacts on Thompson basin coho, further altering marine catch distributions and lowering ocean 0.4 catches of Fraser chinook. 0.3 0.2 pre 1997 Estimates of the distribution of Fraser chinook 1997 on are based on data gathered during coded-wire tag 0.1 (CWT) studies. Because of recent changes in the 0 fishery, catch distribution results were divided FWSP T Inside into pre- and post-1997 when there were sufficient Alaska data to do so. Recoveries for all tags were grouped WA/OR Entry/WCVI Fraser. Comm into one of 7 recovery strata: North-Central Fig. 1. Distribution of estimated CWT recoveries of Recovery Stratum Fishery / Mark Recovery Areas Included upper Fraser spring-run chinook before (n=875), and during or after (n=65), 1997. North, Central All northern and central net, troll and sport fisheries There currently are no CWT application programs WCVI, Entrances All WCVI, Johnstone St. and Juan for mid-Fraser spring-run chinook. A total of 504 de Fuca St. fisheries Inside All Georgia Strait troll, net and CWTs were estimated to have been recovered sport fisheries coastwide from earlier tagging. Similar to upper Fraser River Commercial Fraser gillnet, seine, and test fisheries Fraser springs, most recoveries occurred in the Fresh Water Sport All Fraser River recreational WCVI/Entry area, and many of these were caught fishery recoveries in the Juan de Fuca recreational fishery during Alaska Alaskan troll, seine, and gillnet recoveries June. Washington / Oregon Washington, Oregon and California fisheries A greater proportion of chinook originating in the All CWT information is presented as “estimated North and South Thompson were recovered in tags,” – the numbers of tags recovered in the time- the north and central recovery areas than occurred area-fishery stratum– expanded to account for the for mid and upper Fraser spring chinook (Fig. 2). catch/sample ratio. In many instances, sample Freshwater sport recoveries were almost sizes are small, and our understanding of chinook exclusively in the lower Fraser River bar fishery, distribution is limited as a consequence. First as there were no terminal sport fisheries targetting Nations fisheries in the Fraser have not been these (marked) stocks. 2 Pacific Region Fraser River Chinook Salmon Early returning spring chinook from the 0.3 Birkenhead River (upper Harrison system) had a 0.25 very different marine catch distribution than any other Fraser River spring chinook population (Fig. 0.2 4). Most Birkenhead chinook, one of the earliest 0.15 returning populations to the Fraser, were recovered in Alaskan fisheries. Recoveries inside 0.1 the Strait of Georgia occurred during early spring recreational fisheries. 0.05 0.60 0 0.50 Inside Alaska WA/OR 0.40 FWSPT 0.30 North-Central Entry / WCVI Fraser R. Comm 0.20 Fig. 2. Distribution of estimated CWT recoveries of 0.10 North and South Thompson spring-run chinook (n=485). 0.00 A /OR FWSPT Prior to the closure of many of the outside W Inside Alaska commercial fisheries, recoveries of lower raser Comm Entry / WCVI North-Central Thompson springs occurred in all strata with the F exception of Alaska, but were most common in the WCVI/Entry area (Fig. 3). From 1997 on, the Fig. 4. Distribution of estimated CWT recoveries of Birkenhead spring-run chinook (n=398).