Fishery Manuscript Series No Review of Salmon Escapement Goals in Bristol Bay, Alaska, 2009

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1 Fishery Mnuscript Series No Review of Slmon Escpement Gols in Bristol By, Alsk, 2009 y Timothy T. Bker, Lowell F. Fir, Frederick W. West, Gregory B. Buck, Xinxin Zhng, Steve Fleischmn, nd Jck Erickson Alsk Deprtment of Fish nd Gme Novemer 2009 Divisions of Sport Fish nd Commercil Fisheries

2 Symols nd Arevitions The following symols nd revitions, nd others pproved for the Système Interntionl d'unités (SI), re used without definition in the following reports y the Divisions of Sport Fish nd of Commercil Fisheries: Fishery Mnuscripts, Fishery Dt Series Reports, Fishery Mngement Reports, nd Specil Pulictions. All others, including devitions from definitions listed elow, re noted in the text t first mention, s well s in the titles or footnotes of tles, nd in figure or figure cptions. Weights nd mesures (metric) centimeter deciliter grm hectre kilogrm kilometer liter meter milliliter millimeter cm dl g h kg km L m ml mm Weights nd mesures (English) cuic feet per second ft 3 /s foot ft gllon gl inch in mile mi nuticl mile nmi ounce oz pound l qurt qt yrd yd Time nd temperture dy d degrees Celsius C degrees Fhrenheit F degrees kelvin K hour h minute min second s Physics nd chemistry ll tomic symols lternting current mpere clorie direct current hertz horsepower hydrogen ion ctivity (negtive log of) prts per million prts per thousnd volts wtts AC A cl DC Hz hp ph ppm ppt, V W Generl Alsk Administrtive Code ll commonly ccepted revitions AAC e.g., Mr., Mrs., AM, PM, etc. ll commonly ccepted professionl titles e.g., Dr., Ph.D., R.N., etc. compss directions: est E north N south S west W copyright corporte suffixes: Compny Co. Corportion Corp. Incorported Inc. Limited Ltd. District of Columi D.C. et lii (nd others) et l. et ceter (nd so forth) etc. exempli grti (for exmple) e.g. Federl Informtion Code FIC id est (tht is) i.e. ltitude or longitude lt. or long. monetry symols (U.S.) $, months (tles nd figures): first three letters Jn,...,Dec registered trdemrk trdemrk United Sttes (djective) U.S. United Sttes of Americ (noun) USA U.S.C. United Sttes Code U.S. stte use two-letter revitions (e.g., AK, WA) Mesures (fisheries) fork length mideye to fork mideye to til fork stndrd length totl length FL MEF METF SL TL Mthemtics, sttistics ll stndrd mthemticl signs, symols nd revitions lternte hypothesis H A se of nturl logrithm e ctch per unit effort CPUE coefficient of vrition CV common test sttistics (F, t, χ 2, etc.) confidence intervl CI correltion coefficient (multiple) R correltion coefficient (simple) r covrince cov degree (ngulr ) degrees of freedom df expected vlue E greter thn > greter thn or equl to hrvest per unit effort HPUE less thn < less thn or equl to logrithm (nturl) ln logrithm (se 10) log logrithm (specify se) log 2, etc. minute (ngulr) ' not significnt NS null hypothesis H O percent % proility P proility of type I error (rejection of the null hypothesis when true) α proility of type II error (cceptnce of the null hypothesis when flse) β second (ngulr) " stndrd devition SD stndrd error SE vrince popultion Vr smple vr

3 FISHERY MANUSCRIPT SERIES NO REVIEW OF SALMON ESCAPEMENT GOALS IN BRISTOL BAY, ALASKA, 2009 y Timothy T. Bker, Lowell F. Fir, Frederick W. West, Gregory B. Buck, Xinxin Zhng Alsk Deprtment of Fish nd Gme, Division of Commercil Fisheries, Anchorge nd Steve Fleischmn nd Jck Erickson Alsk Deprtment of Fish nd Gme, Division of Sport Fish, Anchorge Alsk Deprtment of Fish nd Gme Division of Sport Fish, Reserch nd Technicl Services 333 Rsperry Rod, Anchorge, Alsk, Novemer 2009

4 The Fishery Mnuscript series ws estlished in 1987 y the Division of Sport Fish for the puliction of techniclly-oriented results of severl yers' work undertken on project to ddress common ojectives, provide n overview of work undertken through multiple projects to ddress specific reserch or mngement gol(s), or new nd/or highly technicl methods, nd ecme joint divisionl series in 2004 with the Division of Commercil Fisheries. Fishery Mnuscripts re intended for fishery nd other technicl professionls. Fishery Mnuscripts re ville through the Alsk Stte Lirry nd on the Internet: This puliction hs undergone editoril nd peer review. Timothy T. Bker, Lowell F. Fir, Frederick W. West, Gregory B. Buck Alsk Deprtment of Fish nd Gme, Division of Commercil Fisheries, 333 Rsperry Rod, Anchorge, AK 99518, USA nd Steve Fleischmn, nd Jck Erickson Alsk Deprtment of Fish nd Gme, Division of Sport Fish, 333 Rsperry Rod, Anchorge, AK 99518, USA This document should e cited s: Bker, T. T., L. F. Fir, F. W. West, G. B. Buck, X. Zhng, S. Fleischmn, nd J. Erickson Review of slmon escpement gols in Bristol By, Alsk, Alsk Deprtment of Fish nd Gme, Fishery Mnuscript Series No , Anchorge. The Alsk Deprtment of Fish nd Gme (ADF&G) dministers ll progrms nd ctivities free from discrimintion sed on rce, color, ntionl origin, ge, sex, religion, mritl sttus, pregnncy, prenthood, or disility. The deprtment dministers ll progrms nd ctivities in complince with Title VI of the Civil Rights Act of 1964, Section 504 of the Rehilittion Act of 1973, Title II of the Americns with Disilities Act (ADA) of 1990, the Age Discrimintion Act of 1975, nd Title IX of the Eduction Amendments of If you elieve you hve een discriminted ginst in ny progrm, ctivity, or fcility plese write: ADF&G ADA Coordintor, P.O. Box , Juneu, AK U.S. Fish nd Wildlife Service, 4401 N. Firfx Drive, MS 2042, Arlington, VA Office of Equl Opportunity, U.S. Deprtment of the Interior, 1849 C Street NW MS 5230, Wshington DC The deprtment s ADA Coordintor cn e reched vi phone t the following numers: (VOICE) , (Sttewide Telecommuniction Device for the Def) , (Juneu TDD) , or (FAX) For informtion on lterntive formts nd questions on this puliction, plese contct: ADF&G Division of Sport Fish, Reserch nd Technicl Services, 333 Rsperry Rod, Anchorge AK (907)

5 TABLE OF CONTENTS Pge LIST OF TABLES...ii LIST OF FIGURES...ii LIST OF APPENDICES...ii ABSTRACT...1 INTRODUCTION...1 METHODS...2 Escpement Gol Recommendtion...3 Stock-Recruitment Anlysis...3 Risk Anlysis...4 RESULTS AND DISCUSSION...5 Sockeye Slmon...5 Ugshik River...5 Egegik River...5 Nknek River...6 Algnk River...6 Kvichk River...6 Nushgk River...7 Wood River...7 Igushik River...8 Togik River...8 Kulukk River...8 Chinook Slmon...8 Nushgk River...8 Togik River...9 Nknek River...9 Algnk River...9 Egegik River...9 Chum Slmon...9 Nushgk River...9 Coho Slmon...10 Pink Slmon...10 ACKNOWLEDGEMENTS...10 REFERENCES CITED...10 TABLES AND FIGURES...13 APPENDIX A. SOCKEYE SALMON...21 APPENDIX B. CHINOOK SALMON...43 APPENDIX C. CHUM SALMON...55 APPENDIX D. WINBUGS CODE...59 i

6 LIST OF TABLES Tle Pge 1. Bristol By sockeye slmon runs y system, List of memers on the Alsk Deprtment of Fish nd Gme (ADF&G) Bristol By slmon escpement gol committee nd other prticipnts who ssisted with the escpement gol review Summry of current escpement gols nd recommended escpement gols for slmon stocks in Bristol By, Current escpement gols nd estimtes of stock-recruitment prmeters (α, β nd Smsy) for sockeye slmon in Bristol By...17 LIST OF FIGURES Figure Pge 1. Mp of Bristol By showing mjor rivers Kvichk River sockeye slmon lower escpement gols nd numer of spwners, Kernel density estimte of the posterior distriution of lph prmeter in Ricker stock-recruitment nlysis of Kvichk River sockeye slmon during off-cycle nd cycle (pre-pek/pek) yers, , otined from 10,000 itertions of the Gis smpler...20 LIST OF APPENDICES Appendix Pge A1. Escpement gol for Ugshik River sockeye slmon...22 A2. Escpement gol for Egegik River sockeye slmon...24 A3. Escpement gol for Nknek River sockeye slmon...26 A4. Escpement gol for Algnk River sockeye slmon...28 A5. Escpement gol for Kvichk River sockeye slmon...30 A6. Escpement gol for Nushgk River sockeye slmon A7. Escpement gol for Wood River sockeye slmon A8. Escpement gol for Igushik River sockeye slmon A9. Escpement gol for Togik River sockeye slmon...38 A10. Escpement gol for Kulukk River sockeye slmon B1. Escpement gol for Nushgk River Chinook slmon B2. Escpement gol for Togik River Chinook slmon...46 B3. Escpement gol for Nknek River Chinook slmon...48 B4. Escpement gol for Algnk River Chinook slmon...50 B5. Escpement gol for Egegik River Chinook slmon...52 C1. Escpement gol for Nushgk River chum slmon D1. WINBUGS CODE...60 ii

7 ABSTRACT The Alsk Deprtment of Fish nd Gme interdivisionl escpement gol review committee reviewed Pcific slmon Oncorhynchus spp. escpement gols for the mjor river systems in Bristol By. Spwner-return dt were evluted for sockeye slmon O. nerk in the Ugshik, Egegik, Nknek, Kvichk, Algnk, Wood, Nushgk, Igushik, Togik, nd Kulukk Rivers; Chinook slmon O. tshwytsch in the Nushgk, Togik, Algnk, Nknek, nd Egegik Rivers; nd chum slmon O. ket in the Nushgk River. There re currently no escpement gols for coho slmon O. kisutch or pink slmon O. gorusch in ny of the rivers in Bristol By. A totl of 17 escpement gols were evluted for 16 stocks in Bristol By. The committee recommended tht the escpement gol for Togik River sockeye slmon e defined s Sustinle Escpement Gol (SEG) insted of Biologicl Escpement Gol (BEG); however, the current escpement gol rnge would remin unchnged. The committee lso recommended tht the 2 escpement gols (off-cycle nd pre-pek/pek) for sockeye slmon in the Kvichk River e comined into single SEG escpement gol rnge of 2 million to 10 million with recommended exploittion rte of 50% or less. The committee is lso in the process of evluting the effect tht trnsitioning from Bendix sonr to dul frequency identifiction sonr (DIDSON) in the Nushgk River on current escpement gols for Chinook, chum, nd sockeye slmon. The finl step in the trnsition occurred in However, dt from the 2 sonr systems hs not een fully processed nd nlyzed t this time. Key words: Pcific slmon, Oncorhynchus, sockeye slmon, O. nerk, Chinook slmon, O. tshwytsch, chum slmon, O. ket, coho slmon, O. kisutch, pink slmon, O. gorusch, Bristol By, Kvichk River, Algnk River, Nknek River, Egegik River, Ugshik River, Wood River, Igushik River, Nushgk River, Kulukk River, Togik River, spwning escpement gol, Ricker stock-recruitment model, smolt, Alsk Bord of Fisheries. INTRODUCTION Bristol By, Alsk, supports some of the lrgest sockeye slmon Oncorhynchus nerk runs in the world. Comined sockeye slmon runs to Bristol By hve verged pproximtely 39.8 million fish for the lst 20 yers ( ), with 9 mjor river systems producing more thn 99% of the returning sockeye slmon (Ugshik, Egegik, Nknek, Kvichk, Algnk, Wood, Nushgk, Igushik, nd Togik rivers; Tle 1; Figure 1). Mngement of these sockeye slmon runs is sed on chieving spwning escpements for ech river within specific escpement gol rnge. Individul escpement gols for sockeye slmon hve een in plce for the mjor river systems since the erly 1960s (Burgner et l.1967; Fried 1994; Cross et l. 1997; Fir 2000, Fir et l. 2004; Bker et l. 2006). Bristol By lso supports one of the lrgest runs of Chinook slmon O. tshwytsch in Alsk. The Chinook slmon run in the Nushgk River hs verged 150,000 since the 1990s. Smller runs of chum O. ket, coho O. kisutch, nd pink O. gorusch slmon re lso found in the mny rivers of Bristol By. The purpose of this report is to inform the Alsk Bord of Fisheries (ord) nd the pulic of our progress in reviewing nd recommending escpement gols for slmon in Bristol By. Mny slmon escpement gols in Bristol By hve een set nd evluted t regulr intervls since sttehood. During the previous ord cycle, , Bristol By escpement gols were reviewed, nd recommended chnges were mde y the Alsk Deprtment of Fish nd Gme (deprtment; Bker et l. 2006). Recent genetic techniques hve gretly improved the ility to ccurtely determine sockeye slmon stock compositions of the hrvest (Dnn et l. 2009). In Bristol By, these dt re currently ville for the pst 3 yers. However, there is study in progress tht uses previous collected scle smples from hrvests dting ck to 1964 to isolte DNA nd determine prtil historicl hrvest stock compositions. Over the next few yers, the dt gthered from these 1

8 studies will e used to reconstruct rood tles for ech sockeye slmon stock, nd hence, gretly improve our understnding of stock productivity. Becuse of this imminent chnge to the rood tles upon which escpement gols re uilt, the escpement gol committee does not elieve tht mjor chnges to existing gols should occur t this time. Nonetheless, it ws the intention of this review to re-evlute existing dt sets using modern sttisticl nd modeling techniques to estimte escpement levels t mximum sustined yield for comprison to current gols. Non-sockeye slmon escpement gols were evluted, s necessry, in this review. Escpement gols were reviewed sed on the Policy for the Mngement of Sustinle Slmon Fisheries (SSFP; 5 AAC ) nd the Policy for Sttewide Slmon Escpement Gols (EGP; 5 AAC ). The ord dopted these policies into regultion during the winter of to ensure tht the stte s slmon stocks re conserved, mnged, nd developed using the sustined yield principle. Two importnt terms defined in the SSFP were: Biologicl Escpement Gol (BEG): the escpement tht provides the gretest potentil for mximum sustined yield (MSY), nd Sustinle Escpement Gol (SEG): level of escpement, indicted y n index or n escpement estimte, tht is known to provide for sustined yield over 5 to 10 yer period, used in situtions where BEG cnnot e estimted due to the sence of stock specific ctch estimte. The deprtment reviews the escpement gols for Bristol By rivers on schedule tht corresponds to the ord s 3-yer cycle for considering re regultory proposls. This report descries the Bristol By slmon escpement gols tht were reviewed in During the 2009 review process, escpement gols for the following stocks were evluted: Sockeye slmon: Ugshik, Egegik, Nknek, Kvichk (pre-pek/pek nd off-cycle), Algnk, Wood, Nushgk, Igushik, Togik, nd Kulukk rivers; Chinook slmon: Algnk, Egegik, Nknek, Nushgk, nd Togik rivers; nd Chum slmon: Nushgk River. During the spring of 2009, the deprtment estlished n interdivisionl escpement gol review committee (herefter referred to s the committee). The committee consisted of 5 Division of Commercil Fisheries nd 2 Division of Sport Fish personnel (Tle 2). The committee ws formed to provide n nlysis for recommending n escpement gol for ech stock of slmon. The committee formlly met 13 Ferury, 2009 to review escpement gols nd develop recommendtions. The committee lso communicted y emil. All committee recommendtions were reviewed y the deprtment s regionl nd hedqurters stff prior to eing dopted s escpement gols per the SSFP nd EGP (Tle 2). METHODS Aville escpement, ctch, nd ge dt for ech stock were compiled from reserch reports, mngement reports, nd unpulished historicl dtses. The committee evluted the type, qulity, nd quntity of dt for ech stock. This evlution ws used to determine the pproprite type of escpement gol s defined in regultion. Generlly speking, n escpement gol for stock should provide escpement tht produces sustinle yields. An escpement gol for stock ws defined s BEG if sufficiently long time series of escpement, ctch, nd 2

9 ge estimtes were ville; the estimtes were sufficiently ccurte nd precise; nd the dt were considered sufficient to estimte MSY (s per rules nd methods in Chinook Technicl Committee 1999; Hilorn nd Wlters 1992; Quinn nd Deriso 1999). An escpement gol for stock ws defined s n SEG if sufficiently long time series of escpement estimtes were ville, ut there ws concern out the spwner-return dt (lck of ge composition estimtes nd/or concern with stock-specific ctch lloction) or there ws lck of informtion on stock productivity. The committee considered visul counts from towers s good estimtes of escpement nd sonr counts s fir estimtes of escpement. Spwner-return dt were considered good if the escpement qulity ws good nd there were no concerns with estimtes of stock-specific hrvest. Spwner-return dt were considered fir if the qulity of the escpement dt ws fir or there were concerns with estimtes of stock-specific hrvest. The mjority of the lrge slmon stocks in Bristol By hve good escpement nd ge dt, nd in some cses, smolt dt. Sockeye slmon escpement ws smpled y ech seine nd visully counted using towers t Ugshik, Egegik, Nknek, Kvichk, Algnk, Wood, Igushik, nd Togik rivers. Escpement ws smpled y gillnet or ech seine nd estimted using hydrocoustics (sonr) for Nushgk River slmon. Age dt hve een collected from oth the escpement nd hrvest for ll of these stocks. Hrvest lloction for ech stock ws estimted y hrvest loction nd ge composition. Stock contriutions for multi-stock fisheries (Nknek-Kvichk nd Nushgk districts) were estimted sed on ge composition nd run timing of ech stock (West 2003). All other stocks (Kulukk By sockeye slmon; ll Chinook slmon) whose escpements were estimted y eril survey were not smpled for ge composition, nor were their contriutions to hrvest. ESCAPEMENT GOAL RECOMMENDATION In previous reviews, escpement gols were evluted for Bristol By stocks using the following methods: (1) Stock-Recruitment Anlysis; (2) Yield Anlysis; (3) Smolt Informtion; nd (4) Risk Anlysis. Spwner-return dt were used to estimte escpement gols when the committee determined they were good estimtes of totl return (escpement nd stock-specific hrvest) for stock. When good spwner-return dt were ville, escpement gols were estimted sed on: (1) escpements producing verge yields tht were % of MSY from stock-recruitment model, nd 2) the Yield Anlysis, descried in Bker et l. (2006), which lso estimtes MSY with corresponding % yield rnge. Smolt informtion, when ville, ws used to id in the estimtion of escpement gols for stocks. When the hrvest of stock ws deemed coincidentl to hrvests nd mngement of primry stocks (e.g., chum hrvests re coincidentl to the directed hrvests of sockeye nd Chinook slmon in the Nushgk River), the risk nlysis pproch ws used to determine SEG thresholds for these non-trgeted stocks. In this review, the purpose ws not to fully re-evlute ll gols s previously explined, ut rther to pply the most widely ccepted method (stock-recruitment models) to estimte the spwning escpement t MSY, when pplicle, for comprison to current gols. As such, only those methods used in this review re descried elow. Stock-Recruitment Anlysis Stock-recruitment models were used to nlyze slmon spwner-return dt for ll ville rood yers. For this nlysis, spwners were nlogous to stock nd return nlogous to 3

10 recruitment. Totl returns were the sum of escpements nd hrvests. Methods used to estimte totl return (hrvest plus escpement) were descried in Bernrd (1983). Sport nd susistence hrvests were only included in totl return estimtes for the Nushgk River Chinook slmon, nd were considered minor components for the other stocks. The most commonly used Stock-Recruitment (S-R) models re the Ricker (1954) nd the Beverton-Holt (1957) models. These models re governed y the following equtions, respectively: R = αse βs αs R = α 1+ S β where α nd β re prmeters in these models. A Byesin pproch ws used to estimte these prmeters in the models. We used multiplictive error Byesin nlysis hs een used for the stock-recruitment dt nlysis for Ricker (Rivot et l. 2001) nd Beverton-Holt (McAllister et l. 2001) models. The deprtment hs lso pplied Byesin pproch to Ricker models in previous escpement gol studies (Der Hovnisin et l. In prep.). We ssumed multiplictive error for oth models. The nlysis in this report ws similr to the previous deprtment studies, ut it differs in three spects. First, the seril correltion ws not explicitly considered in the model. Autocorreltion cn e serious prolem in non-byesin nlysis ecuse utocorreltion leds to worse time-series is (Wlters 1985 nd 1990). However, fter Kormn et l. (1995) exmined sockeye stocks in Bristol By, Alsk, they concluded it ws not worth pplying is-correction method. Second, the prmeter α ws not corrected for the logrithm trnsformtion is using the formuls from Hilorn nd Wlters (1992). Tht correction ws used for the men of n estimted prmeter (Hilorn nd Mngel 1997). It ws not pproprite to mke the correction for the posterior distriution of prmeter within the Byesin frmework. Third, different uninformtive priors (Meyer nd Millr 2000) were pplied. For the detil of the Byesin models, refer to Appendix D. Hving estimtes of α nd β, the fishery mngement prmeter, S msy (the optiml stock size t MSY), ws clculted sed on the formultions from Hilorn nd Wlters (1992). To generte smples from the posterior distriution, Mrkov Chin Monte Crlo (MCMC) chin ws simulted, with 20,000 itertions. The first hlf of the sequence ws discrded nd convergence ws checked. The nlyses were done using WinBUGS (Byesin Inference Using Gis Smpling) (Spiegelhlter et l. 1996). Risk Anlysis For stocks tht were pssively mnged nd coincidentlly hrvested, SEG thresholds (Bernrd et l. 2009) were estimted. The 6 gols previously developed using these procedures were: Kulukk River sockeye slmon; Algnk, Egegik, Nknek, nd Togik rivers Chinook slmon; nd Nushgk River chum slmon. The nture of the risk nlysis pproch does not lend itself to necessry updte with every 3 yers of dditionl dt; therefore, we did not re-nlyze the dt for this review. 4

11 RESULTS AND DISCUSSION A totl of 17 escpement gols were evluted for 16 stocks in Bristol By. The committee recommended tht the escpement gol for Togik River sockeye slmon e defined s n (SEG) insted of BEG; however, the current escpement gol rnge would remin unchnged from the 2000 review (Fir 2000; see lso Tle 3). The committee lso recommended tht the 2 escpement gols (off-cycle nd pre-pek/pek) for sockeye slmon in the Kvichk River e comined into single SEG escpement gol rnge of 2 million to 10 million with recommended exploittion rte of 50% or less. The committee is lso in the process of evluting the effect tht trnsitioning from Bendix sonr to DIDSON in the Nushgk River will hve on current escpement gols for Chinook, chum, nd sockeye slmon. The finl step in the trnsition occurred in However, dt from the 2 sonr systems hve not een fully processed nd nlyzed t this time. The committee recommended no chnge to the current SEG rnges for sockeye slmon in the Ugshik, Egegik, Nknek, Algnk, Nushgk, Wood, nd Igushik rivers (Tle 3; Appendices A1 A9). The committee did not formlly evlute the escpement gols for sockeye slmon in these rivers. Non-trgeted sockeye slmon stocks were identified in the commercil hrvest in ll the fishing districts in Bristol By sed on genetic stock composition estimtes (Dnn et l. 2009). These genetic stock composition estimtes will llow deprtment to produce new estimtes of totl run nd production (rood tle) for sockeye slmon in ech river. The deprtment nticiptes this will occur in 3 5 yers nd plns to re-evlute escpement gols for sockeye slmon once new totl run nd rood tles re completed. The recommendtion for ech escpement gol follows y species nd river. The detiled informtion for ech escpement gol cn e found in the previous escpement gol reports (Bker et l. 2006; Fir et l. 2004). Recent nd historicl dt used for ech escpement gol nlysis is locted in Appendices A C. SOCKEYE SALMON Ugshik River No chnge ws recommended to the current SEG rnge of 500,000 to 1,200,000 sockeye slmon for Ugshik River (Tle 3; Appendix A1). Escpement ws within the escpement gol rnge in 8 of the lst 10 yers (Appendix A1). Escpement verged 853,000; totl return verged million, nd return per spwner (R/S) verged 4.32 sockeye slmon nnully from The current SEG rnge is elow the spwning escpement tht produces Mximum Sustined Yield (S msy ) sed on n nlysis of S-R dt (Tle 4). Egegik River No chnge ws recommended to the current SEG rnge of 800,000 to 1,400,000 sockeye slmon for Egegik River (Tle 3; Appendix A2). Escpement ws within the escpement gol rnge in 6 of the lst 10 yers (Appendix A2). Escpement verged million sockeye slmon, totl return verged million, nd R/S verged 5.88 sockeye slmon nnully from The current SEG rnge is elow S msy sed on n nlysis of S-R dt (Tle 4). 5

12 Nknek River No chnge ws recommended to the current SEG rnge of 800,000 to 1,400,000 sockeye slmon for Nknek River (Tle 3; Appendix A3). Escpement ws within the escpement gol rnge in 2 of the lst 10 yers nd within the optimum escpement gol rnge (800,000 to 2,000,000) 7 out of the lst 10 yers (Appendix A3). Escpement verged million, totl return verged million, nd R/S verged 3.23 sockeye slmon nnully from The current SEG rnge is elow S msy sed on n nlysis of S-R dt (Tle 4). Algnk River No chnge ws recommended to the current minimum SEG threshold of 320,000 sockeye slmon for Algnk River (Tle 3; Appendix A4). The SEG threshold ws exceeded in 10 of the lst 10 yers (Appendix A4). Escpement verged 469,000, totl return verged million, nd R/S verged 3.83 sockeye slmon nnully from The current SEG rnge is elow S msy sed on n nlysis of S-R dt (Tle 4). This Algnk River stock is pssively mnged nd coincidentlly hrvested with the Kvichk River stock. Therefore, the deprtment is not le to ctively mnge this stock nd otin n escpement gol rnge. It is for this reson tht n SEG threshold ws estlished for this stock nd not n escpement gol rnge. Historiclly, Algnk River ws not considered lrge producer of sockeye slmon compred to the Kvichk River nd some of the sockeye slmon stocks in Bristol By. However, since 2003 escpement to Algnk River hs verged million sockeye slmon. We do not yet know the totl return from these lrge escpements. However, we should not e surprised y the recent production increse for Algnk River. Schindler et l. (2006) used sediment cores to show tht periods of high sockeye slmon undnce hve occurred in Algnk River pproximtely every 100 yers for the lst 5 centuries. Kvichk River The committee recommends chnge to the Kvichk River sockeye slmon escpement gol. Currently, there re 2 gols: one for off-cycle yers, nd one for pre-pek nd pek yers. The current SEG for Kvichk River sockeye slmon is 2 million to 10 million for off-cycle yers nd 6 million to 10 million for pre-pek nd pek yers (Tle 3; Appendix A5). Escpement ws within the escpement gol rnge in 4 out of the lst 7 off-cycle yers ( ) nd 1 out of the lst 3 pre-pek/pek yers ( ; Appendix A5). The pre-pek/pek escpement gol hs not een met since 1999; 2005 ws chnged from pek to off-cycle yer. Escpement verged million, totl return verged million, nd R/S verged 2.27 sockeye slmon nnully during off-cycle yers from Escpement verged million, totl return verged million, nd R/S verged 2.45 sockeye slmon nnully during pre-pek nd pek yers from Escpement verged million, totl return verged million, nd R/S verged 2.34 sockeye slmon during ll yers from The recommended SEG rnge of 2 million to 10 million for ll yers is elow S msy sed on n nlysis of S-R dt (Tle 4). Setting n escpement gol for Kvichk River sockeye slmon run hs proven difficult ecuse of the perceived divergence in productivity etween off-cycle nd cycle (pre-pek nd pek) yers; poor density dependence found in the spwner-return dt; nd susequent lck of fit for stock-recruitment models. To help chieve escpements within the gol rnge nd provide 6

13 hrvest opportunity, mximum exploittion rte of 50% ws estlished for Kvichk River runs of 4 million to 20 million. For exmple, the mngement ojective for n off-cycle yer is 50% of the totl inshore run, never to e less thn 2 million or greter thn 10 million. From 1996 through 2004, 7 of 9 yers experienced escpements elow the lower end of the escpement gol rnge (Figure 2). Since 2005, the lower end of the gol hs een chieved ech yer. In recent yers, the ility to define pre-pek or pek run ws mde incresingly difficult s the runs declined. A pre-pek/pek gol, lrgely composed of 5-yer-old 2-ocen fish, ws originlly estlished in the 1960s (Rogers nd Poe 1984) ecuse it ws elieved tht production differed from tht of off-cycle yers. Therefore, it ws dvntgeous to seprte them. However, with the new dt ville, we updted the nlysis for compring production etween pre-pek/pek versus off-cycle yers. Ricker S-R nlyses were conducted seprtely for off-cycle nd pre-pek/pek yers. Alph (α) prmeters from the Ricker S-R nlyses were used to compre the productivity etween off-cycle nd pre-pek/pek yers (Figure 3). The results show similrity in the underlying productivity during off-cycle nd pre-pek/pek yers. In ddition, we re no longer le to identify off-cycle nd pre-pek/pek yers. For instnce, in 1983 (which ws identified s n off-cycle yer), the totl run ws lrge nd looked more like pre-pek or pek yer thn n off-cycle yer. More recently, 2005 nd 2009 (which were identified s pek nd pre-pek yers), the totl runs were smll nd looked more like off-cycle yers thn pre-pek or pek yer. It ws for these resons the committee recommended tht the pre-pek/pek gol of 6 million to 10 million e dropped nd tht the off-cycle gol of 2 million to 10 million expnded to include ll yers with recommended 50% exploittion rte. The recommended chnge of the escpement gol for Kvichk River sockeye slmon ws lso supported y n nlysis completed y Ruggerone nd Link (2006). Their nlysis did not support the existing escpement gol policy of higher escpement levels (6 to 10 million fish) during pek nd pre-pek return yers compred to other return yers (2 to 6 million). They concluded tht mintennce of the Kvichk River sockeye slmon cycle through mngement ctions does not pper necessry for high slmon productivity nd hrvestle surpluses. A similr conclusion ws lso reched y Rogers nd Poe (1984). Nushgk River No chnge ws recommended for the current SEG rnge of 340,000 to 760,000 sockeye slmon for Nushgk River (Tle 3; Appendix A6). Escpement ws within the escpement gol rnge in 7 of the lst 10 yers (Appendix A6). Escpement verged 661,000, totl return verged million, nd R/S verged 3.51 sockeye slmon nnully from The current SEG rnge is slightly elow the spwning escpement tht produces MSY (S msy ) sed on n nlysis of S-R dt (Tle 4). The committee is lso in the process of evluting the effect tht trnsitioning from Bendix sonr to DIDSON in the Nushgk River will hve on the current escpement gol for sockeye slmon. The finl step in the trnsition occurred in However, dt from the 2 sonr systems hve not een fully processed nd nlyzed t this time. Preliminry results my e ville t the Bristol By ord meeting in Decemer Wood River No chnge ws recommended to the current SEG rnge of 700,000 to 1,500,000 sockeye slmon for the Wood River (Tle 3; Appendix A7). Escpement ws within the escpement gol rnge 7

14 in 5 of the lst 10 yers (Appendix A7). Escpement verged million, totl return verged million, nd R/S verged 2.88 sockeye slmon nnully from The current SEG rnge is elow S msy sed on n nlysis of S-R dt (Tle 4). Igushik River No chnge ws recommended to the current SEG rnge of 150,000 to 300,000 sockeye slmon for Igushik River (Tle 3; Appendix A8). Escpement ws within the escpement gol rnge in 3 of the lst 10 yers (Appendix A8). Escpement verged 346,000, totl return verged 976,000, nd R/S verged 4.49 sockeye slmon nnully from The current SEG rnge is elow S msy sed on n nlysis of S-R dt (Tle 4). Togik River The committee recommended chnging the escpement gol for sockeye slmon in Togik River from BEG to n SEG due to ctch lloction issues within the Togik District. Sustntil numers of non-togik stocks were identified in the commercil ctch sed on genetics stock composition estimtes (Dnn et l. 2009). Chnging Togik sockeye from BEG to SEG is similr to wht ws done for most sockeye slmon stocks in Bristol By in 2006 (Bker et l. 2006). Additionlly, the committee recommends no chnge to the current escpement gol rnge of 120,000 to 270,000 (Tle 3; Appendix A9) tht ws sed on n escpement gol nlysis for this stock tht ws completed in 2003 (Fir et l. 2004). The escpement gol rnge includes 100,000 to 250,000 tower counts nd 20,000 expnded eril survey counts tht re considered dditionl to the Togik towers counts (Bker et l. 2006; Fir et l. 2004). Escpement ws within the escpement gol rnge in 6 of the lst 10 yers (Appendix A9). Escpement verged 182,000, totl return verged 559,000, nd R/S verged 3.48 sockeye slmon nnully from The current SEG rnge is close to S msy sed on n nlysis of S-R dt (Tle 4). Kulukk River The committee ws unle to evlute the current escpement gol for sockeye slmon in Kulukk River ecuse no eril surveys were flown in the Kulukk River system from The Kulukk River escpement gol is currently n SEG threshold of 8,000 eril survey counts (Tle 3; Appendix A10; Bker et l 2006; Fir et l. 2004). Escpement exceeded the SEG threshold in 5 out of 5 yers from (Appendix A10). The committee recommends tht eril surveys of the Kulukk River system e flown to evlute this escpement gol in the future. CHINOOK SALMON Nushgk River No chnge ws recommended to the current SEG rnge of 40,000 to 80,000 Chinook slmon for Nushgk River (Tle 3; Appendix B1). Escpement ws within the escpement gol rnge in 4 of the lst 10 yers (Appendix B1). Escpement verged 79,507 Chinook slmon from , producing n verge totl return of 165,329 with n verge return per spwner of 2.61 nnully. The committee is lso in the process of evluting the effect tht trnsitioning from Bendix sonr to DIDSON in Nushgk River will hve on the current escpement gol for Chinook slmon. 8

15 Togik River The committee ws unle to evlute the current escpement gol for Chinook slmon in Togik River ecuse very few eril surveys were flown in the Togik River system for Chinook slmon from The Togik escpement gol is currently n SEG threshold of 9,300 eril survey counts with no upper ounds (Tle 3; Appendix B2). Escpement exceeded the SEG threshold in 4 out of 4 yers ( ). Escpement ws not estimted in The committee recommends tht eril surveys of the Togik River system e flown to evlute this escpement gol in the future. Nknek River No chnge ws recommended to the current SEG threshold of 5,000 Chinook slmon (Tle 3; Appendix B3). The escpement gol for Chinook slmon in the Nknek River ws sed on eril survey estimtes. The gol ws estimted using the risk nlysis pproch with escpement dt eginning in 1971 (Bker et l. 2006; Fir et l. 2004). Escpement hs verged 5,969 Chinook slmon from (Appendix B3). Escpements exceeded the SEG threshold in 6 out the 7 yers ( ; ). Escpement ws not estimted in 1999 nd Algnk River No chnge ws recommended to the current SEG threshold of 2,700 Chinook slmon (Tle 3; Appendix B4). The escpement gol for Chinook slmon in Algnk River ws sed on eril survey estimtes. The gol ws estimted using the risk nlysis pproch with escpement dt eginning in 1970 (Bker et l. 2006; Fir et l. 2004). Escpement verged 4,931 Chinook slmon from (Appendix B4). Escpements exceeded the SEG threshold in 7 out of the lst 10 yers ( ). Egegik River No chnge ws recommended to the current SEG threshold of 450 Chinook slmon (Tle 3; Appendix B5). The escpement gol for Chinook slmon in Egegik River ws sed on eril survey estimtes. The gol ws estimted using the risk nlysis pproch with escpement dt eginning in 1985 (Bker et l. 2006; Fir et l. 2004). Escpement estimtes were the sum of eril surveys from Gertrude, Kye s, nd Tkyoto creeks only. Escpement hs verged 547 Chinook slmon from (Appendix B5). Escpements exceeded the SEG threshold in 4 out of the lst 10 yers ( ). CHUM SALMON Nushgk River No chnge ws recommended to the current SEG threshold of 190,000 Chum slmon (Tle 3; Appendix C1). This escpement gol ws sed on sonr counts nd estlished using the risk nlysis pproch (Bker et l. 2006; Fir et l. 2004). Escpement hs verged 308,945 chum slmon from (Appendix C1). Escpements exceeded the SEG threshold in 8 out of the lst 10 yers ( ). 9

16 COHO SALMON There re currently no escpement gols for coho slmon in Bristol By. Coho slmon escpement gols for Nushgk, Togik, nd Kulukk rivers were dropped in 2006 (Bker et l. 2006). These gols were dropped ecuse the deprtment no longer estimtes coho slmon escpement in these 3 rivers. PINK SALMON There re currently no escpement gols for pink slmon in Bristol By. The pink slmon escpement gol in the Nushgk River ws dropped in 2006 (Bker et l. 2006). The Nushgk River pink slmon gol ws dropped ecuse the deprtment no longer estimtes pink slmon escpement in Nushgk River. ACKNOWLEDGEMENTS The uthors wish to thnk the memers of the escpement gol committee nd prticipnts in the escpement gol review. REFERENCES CITED Bker, T. T., L. F. Fir, R. A. Clrk, nd J. J. Hsrouck Review of slmon escpement gols in Bristol By, Alsk, Alsk Deprtment of Fish nd Gme, Fishery Mnuscript No , Anchorge. Bernrd, D. R Vrince nd is of ctch lloctions tht use the ge composition of escpements. Alsk Deprtment of Fish nd Gme, Division of Commercil Fisheries, Informtionl Leflet No. 227, Anchorge. Bernrd, D. R., J. J. Hsrouck, B. G. Bue, nd R. A. Clrk Estimting risk of mngement error from precutionry reference points (PRPs) for non-trgeted slmon stocks. Alsk Deprtment of Fish nd Gme, Specil Puliction No , Anchorge. Beverton, R. J. H, nd S. J. Holt On the dynmics of exploited fish popultions. Chpmn & Hll, London. Burgner, R. L., C. J. DiCostnzo, R. L. Ellis, G. Y. Hrry, Jr., W. L. Hrtmn, O. E. Kerns, Jr., O. A. Mthisen, nd W. F. Royce Biologicl studies nd estimtes of optimum escpement s of sockeye slmon in the mjor river systems in Southwestern Alsk. Fishery Bulletin 67: United Sttes Fish nd Wildlife Service, Wshington, D.C. Chinook Technicl Committee Mximum sustined yield of iologiclly sed escpement gols for selected Chinook slmon stocks used y the Pcific Slmon Commission s Chinook Technicl Committee for escpement ssessment, Volume I. Pcific Slmon Commission Joint Chinook Technicl Committee Report No. TCHINOOK (99)-3, Vncouver, British Columi, Cnd. Clrk, J. H Aundnce of sockeye slmon in the Algnk River system of Bristol By Alsk. Alsk Deprtment of Fish nd Gme, Fishery Mnuscript No , Anchorge. Cross, B. A., D. C. Gry, nd D. L. Crwford Report to the Alsk Bord of Fisheries on spwning escpement gol evlutions for Bristol By slmon. Alsk Deprtment of Fish nd Gme, Division of Commercil Fisheries, Regionl Informtion Report 2A97-30, Anchorge. Dnn, T. H., C. Hicht, J. A. Jsper, H. Hoyt, W. D. Templin, T. T. Bker, F. W. West, nd L. F. Fir Genetic stock composition of the commercil hrvest of sockeye slmon in Bristol By, Alsk, Alsk Deprtment of Fish nd Gme, Fishery Mnuscript No , Anchorge. 10

17 REFERENCES CITED (Continued) Der Hovnisin, J. A, S. J. Fleischmn, nd S. A. McPherson. In prep. Escpement gols for Chinook slmon in the Blossom nd Ket rivers. Alsk Deprtment of Fish nd Gme, Fishery Mnuscript, Anchorge. Fir, L. F Report to the Alsk Bord of Fisheries on spwning escpement gol evlutions for Bristol By slmon. Alsk Deprtment of Fish nd Gme, Division of Commercil Fisheries, Regionl Informtion Report 2A00-38, Anchorge. Fir, L. F Criticl elements of Kvichk River sockeye slmon mngement. Alsk Fishery Reserch Bulletin 10(2): Fir, L. F., B. G. Bue, R. A. Clrk, nd J. J. Hsrouck Spwning escpement gol review of Bristol By slmon stocks. Alsk Deprtment of Fish nd Gme, Division of Commercil Fisheries, Regionl Informtion Report 2A04-17, Anchorge. Fried, S. M Pcific slmon spwning escpement gols for the Prince Willim Sound, Cook Inlet, nd Bristol By res of Alsk. Alsk Deprtment of Fish nd Gme, Commercil Fisheries Mngement nd Development Division, Specil Puliction No. 8, Juneu. Hilorn, R., nd C. J. Wlters Quntittive fisheries stock ssessment choice, dynmics nd uncertinty. Chpmn nd Hll, New York. Hilorn, R. nd M. Mngel The Ecologicl Detective: Confronting Models with Dt. Princeton University Press, Princeton, N.J. Kormn, J., R. M. Petermn, nd C. J. Wlters Empiricl nd theoreticl nlyses of correction of timeseries is in stock-recruitment reltionships of sockeye slmon (Oncorhynchus nerk). Cndin Journl of Fisheries nd Aqutic Sciences 52: McAllister, M., E. A. Bcock, E. K. Pikitch Using Byesin methods to improve stock ssessment nd mngement of stock reuilding when there is uncertinty in processes ffecting future recruitment. Collective Volume of Scientific Ppers, Interntionl Commission for the Conservtion of Atlntic Tuns 52(3): Meyer, R., nd R. B. Millr Byesin dynmic modeling of stock-recruitment reltionships. Postscript pper. Deprtment of Sttistics, University of Aucklnd, Aucklnd, N.Z. Quinn II, T. J. nd R. B. Deriso Quntittive fish dynmics. Oxford University Press. New York, NY. Ricker, W. E Stock nd recruitment. Journl of the Fisheries Reserch Bord of Cnd, 11: Rivot, E., E. Prévost, nd E. Prent How roust re Byesin posterior inferences sed on Ricker model with regrds to mesurement errors nd prior ssumptions out prmeters? Cndin Journl of Fisheries nd Aqutic Sciences. 58: Rogers. D. E. nd P. H. Poe Escpement gols for the Kvichk River system. Finl Report to the Alsk Deprtment of Fish nd Gme, Contrct No Fisheries Reserch Institute, School of Fisheries, University of Wshington, FRI-UW Settle. Ruggerone, G. T., nd M. R. Link Collpse of Kvichk sockeye slmon production rood yers : Popultion chrcteristics, possile fctors, nd mngement implictions. Unpulished report prepred y Nturl Resources Consultnts, Inc. nd LGL Alsk Reserch Assocites, Inc. for the North Pcific Reserch Bord, Anchorge, AK. xv + 104p. Schindler, D. E., P. R. Levitt, S. P. Johnson, nd C. S. Brock A 500-yer context for the recent surge in sockeye slmon (Oncorhynchus nerk) undnce in the Algnk River, Alsk. Cndin Journl of Fisheries nd Aqutic Sciences 63: Spiegelhlter, K. J., A. Thoms, N. G. Best, nd W. R. Gilks BUGS 0.5 Byesin inference using Gis smpling. Mnul (Version ii). Medicl Reserch Council Biosttistics Unit, Institute of Pulic Helth, Cmridge, Englnd. 11

18 REFERENCES CITED (Continued) Wlters, C. J Bis in the estimtion of functionl reltionships from time-series dt. Cndin Journl of Fisheries nd Aqutic Sciences 42: Wlters, C. J A prtil is correction fctor for stock-recruitment prmeter estimtion in the presence of utocorrelted environmentl effects. Cndin Journl of Fisheries nd Aqutic Sciences 47: West, F. W Aundnce, ge, sex, nd size sttistics for Pcific slmon in Bristol By, Alsk Deprtment of Fish nd Gme, Division of Commercil Fisheries, Regionl Informtion Report 2A03-23, Anchorge. 12

19 TABLES AND FIGURES 13

20 Tle 1. Bristol By sockeye slmon runs y system, Yer Algnk Egegik Igushik Kvichk Nknek Nushgk Togik Ugshik Wood Totl ,456,715 10,982,191 1,253,349 20,546,578 3,303,545 1,260, ,897 5,050,591 2,600,575 46,632, ,516,487 12,931,907 1,316,384 17,987,984 8,675,471 1,797, ,723 2,981,747 2,687,768 50,238, ,653,055 9,938,490 2,513,393 8,329,427 10,285,373 1,800, ,953 5,628,628 3,425,986 44,379, ,349,201 18,616, ,190 10,969,092 5,326,773 1,898, ,259 5,831,415 2,571,473 48,255, ,257,608 24,482,294 1,661,902 9,901,802 4,905,544 2,330, ,395 5,912,728 3,936,201 56,085, ,734,602 12,998,622 1,379,741 22,734,661 3,144,481 1,618, ,040 5,605,154 3,111,319 52,848, ,780,539 16,200,744 1,989,745 28,330,238 3,700, , ,293 6,040,598 4,191,837 63,797, ,917,409 12,253,454 1,513,712 3,538,322 7,076,263 1,804, ,898 5,237,440 5,159,244 39,086, ,409 9,363, ,691 1,828,355 1,514, , ,240 2,238,765 3,631,149 20,765, ,072,427 5,090, ,086 3,553,651 2,747, , ,741 1,785,676 4,143,028 20,261, ,843,135 9,406,998 1,626,796 13,307,746 3,969, , ,234 4,059,544 6,160,257 42,931, ,015,717 8,402,918 1,812,539 3,031,259 4,934,554 1,528,710 1,126,843 2,300,351 5,544,371 30,697, ,106,307 3,867,625 1,324,241 1,435,570 6,683,792 2,126,312 1,109,256 1,356,025 4,014,038 23,023, ,267 5,840, , ,026 2,774, , ,290 2,563,837 3,842,244 17,825, ,789,818 3,502,937 1,035,722 1,750,692 5,183,655 2,273, ,566 2,582,872 5,744,224 26,761, ,776,427 12,857, ,506 7,758,677 3,996,000 2,432, ,297 4,148,186 5,625,181 44,692, ,301,016 9,625,859 1,878,030 2,877,518 7,806,032 3,442, ,478 3,001,814 4,770,667 39,268, ,804,574 8,873,391 1,434,887 5,756,121 5,385,265 3,238, ,755 3,432,755 11,064,404 42,876, ,277,498 7,928,408 1,762,291 4,230,592 8,736,347 2,579,855 1,086,227 7,625,801 6,523,544 44,750, ,907,154 8,663,453 3,294,374 5,631,801 6,253,993 1,644, ,995 2,930,354 5,236,278 40,418,833 Men 2,551,718 10,591,339 1,417,924 8,711,406 5,320,220 1,804, ,669 4,015,714 4,699,189 39,779,857 Medin 1,848,974 9,516,429 1,407,314 5,693,961 5,059,105 1,798, ,647 3,746,150 4,167,433 42,904,234 Min 681,409 3,502, , ,026 1,514, , ,897 1,356,025 2,571,473 17,825,459 Mx 6,776,427 24,482,294 3,294,374 28,330,238 10,285,373 3,442,172 1,126,843 7,625,801 11,064,404 63,797,483

21 Tle 2. List of memers on the Alsk Deprtment of Fish nd Gme (ADF&G) Bristol By slmon escpement gol committee nd other prticipnts who ssisted with the escpement gol review. Nme Position Affilition Escpement Gol Committee: Timothy Bker Are Reserch Biologist ADF&G, Division of Commercil Fisheries Lowell Fir Regionl Reserch Biologist ADF&G, Division of Commercil Fisheries Fred West Asst. Are Reserch Biologist ADF&G, Division of Commercil Fisheries Greg Buck Asst. Are Reserch Biologist ADF&G, Division of Commercil Fisheries Xinxin Zhng Regionl Biometricin ADF&G, Division of Commercil Fisheries Steve Fleischmn Fisheries Scientist ADF&G, Division of Sport Fish Jck Erickson Regionl Reserch Biologist ADF&G, Division of Sport Fish Other Prticipnts: Erik Volk Chief Fisheries Scientist ADF&G, Division of Commercil Fisheries Jeff Regnrt Regionl Supervisor ADF&G, Division of Commercil Fisheries Dn Gry Regionl Mngement Biologist ADF&G, Division of Commercil Fisheries Slim Morstd Are Mngement Biologist ADF&G, Division of Commercil Fisheries Tim Snds Are Mngement Biologist ADF&G, Division of Commercil Fisheries Pul Slomone Are Mngement Biologist ADF&G, Division of Commercil Fisheries Mtt Jones Asst. Are Mngement Biologist ADF&G, Division of Commercil Fisheries Jim Hsrouck Regionl Supervisor ADF&G, Division of Sport Fish Mtt Miller Regionl Mngement Biologist ADF&G, Division of Sport Fish Json Dye Are Mngement Biologist ADF&G, Division of Sport Fish Crig Schwnke Asst. Are Mngement Biologist ADF&G, Division of Sport Fish 15

22 Tle 3. Summry of current escpement gols nd recommended escpement gols for slmon stocks in Bristol By, Current Escpement Gol Recommended Escpement Gol Yer Escpement System Gol Type Adopted Dt Action Gol Type Sockeye Slmon Ugshik 500,000 1,200,000 SEG 1995; Chnged to SEG in 2006 Tower No Chnge Egegik 800,000 1,400,000 SEG 1995; Chnged to SEG in 2006 Tower No Chnge Nknek 800,000 1,400,000 SEG 1984; Chnged to SEG in 2006 Tower No Chnge Chnge to single Kvichk (off-cycle) 2,000,000 10,000,000 SEG 1997; Chnged to SEG in 2006 Tower gol 2,000,000 10,000,000 SEG Kvichk (pre, pek) 6,000,000 10,000,000 SEG 1997; Chnged to SEG in 2006 Tower Chnge to single gol 2,000,000 10,000,000 SEG Algnk 320,000 minimum SEG 2006 Tower No Chnge Wood 700,000 1,500,000 SEG 2000; Chnged to SEG in 2006 Tower No Chnge Nushgk 340, ,000 SEG 1997; Chnged to SEG in 2006 Sonr No Chnge Igushik 150, ,000 SEG 2000; Chnged to SEG in 2006 Tower No Chnge Togik 120, ,000 BEG 1997 Tower Chnge to SEG 120, ,000 SEG Kulukk By 8,000 minimum SEG 2006 Aeril No Chnge Chinook Slmon Nushgk 40,000 80,000 SEG 2006; Chnged to SEG in 2006 Sonr No Chnge Togik 9,300 minimum SEG 2006 Aeril No Chnge Nknek 5,000 minimum SEG 2006 Aeril No Chnge Algnk 2,700 minimum SEG 2006 Aeril No Chnge Egegik 450 minimum SEG 2006 Aeril No Chnge Chum Slmon Nushgk 190,000 minimum SEG 2006 Sonr No Chnge

23 Tle 4. Current escpement gols nd estimtes of stock-recruitment prmeters (α, β nd Smsy) for sockeye slmon in Bristol By. 17 Escpement Gol Spwner- α β Smsy Gol (x thousnds) Return 95% CI 95% CI 95% CI River Type Lower Upper Dt n Model Medin Lower Upper Medin Lower Upper 1/β Medin Lower Upper Ugshik SEG 500 1, Ricker ,241 2, ,410 Beverton-Holt ,481 3,013 99,080 2, ,420 Egegik SEG 800 1, Ricker ,804 6,226 1, ,200 Beverton-Holt ,370 9, ,600 8,871 2, ,900 Nknek SEG 800 1, Ricker ,483 1,947 1,206 8,616 Beverton-Holt ,673 4,010 31,500 1, ,745 Algnk SEG Ricker , ,649 Beverton-Holt ,253 1,312 27, ,533 Kvichk SEG 2,000 10, Ricker ,962 16,040 5, ,100 Beverton-Holt ,990 18,420 1,520,000 13,550 4, ,300 Nushgk SEG Ricker , ,106 Beverton-Holt Model did not converge Wood SEG 700 1, Ricker ,103 1,639 1,005 6,446 Beverton-Holt ,306 3,958 49,600 2, ,730 Igushik SEG Ricker Beverton-Holt Model did not converge Togik SEG Ricker Beverton-Holt , Bristol By SEG 5,730 16, Ricker ,387 14,340 29, ,600 Beverton-Holt ,900 61,070 1,750,000 15,160 37, ,500 Note: A Byesin nlysis ws used to estimte stock-recruitment prmeters for Ricker nd Beverton-Holt models. Multiplictive error ws ssumed for oth models. Medin prmeter estimtes were reported long with lower nd upper 95% credile intervls (95% CI). Blnk cells were tht dt which did not fit the models.

24 18 Figure 1. Mp of Bristol By showing mjor rivers.