stock assessment for fishery management a framework guide to the stock potx

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fishery management Stock assessment for

A framework guide to the stock assessment tools

of the Fisheries Management Science Programme

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Stock assessment for TECHNICAL risus

PAPER

fishery management 437

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The desgutons employe and he preerason af mati shisinloemason rodet swe tpl the expr of ay opinion rhaseog ơn tp ‘like Food aad Agrsoure Onguaton of he United Nations soncerning te Igor developmen sta sy can team se eo atone ‘concering the dnitation of fis oe boro

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Regrettably, while this volume was in press, we heard of the death of Dr Geoff Kirkwood Geoff had been instrumental in developing many of the techniques that are outline in this document and his frends and

colleagues, a well as fisheries science

in generl, wil miss him greatly

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Preparation of this document

These guidelines are intended to assise fishery sciemtists in using a set of stock: assessment computer progeams, developed as part of elfors of the UK Department for International Development (DFID, previously ODA) and the Fisheries Department of the Food and Agriculture Organization of the United Nations (FAO) to disseminate appropriate methodologies to the developing world, The software and this supporting documentation are the outcome of a series of studies funded by DEID under its Hisheries Management Science Progeanme (FMSP) The collation and publication of this document in English, by FAO, ws supported by FMSP projcsr R89 “The CD:ROM incloded with ths paper provides the installation files for exch ofthe four FMSP sofeware programs for fish stock assessment: {Length Frequency Dieribuion Analysis (LEDA\,

2.Gatch and Etfort Data Analysis (CEDAY, 3 Yield snd

4-Pancipatory Fisheries Stock Assessment (PaeFish) including toolkit “These installation fies ae also availabe on the FMSP Web sit at hispyrwwehmep.orguk

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Abstract

This paper provides guidelines for fish stosk assessment and fishery management using the soltware tools and other outpots developed by the UK Department for Taernational Development's Fisheries Management Science Progeamme (FMSP) in

the years 1992 t0 2094 Pace 1 describes some key elements of the precautionary approach ta fisheries management, & stock assessment process s also outlined that can provide the information needed for such precautionary management, The management process summarized in Chapter 2 i based on recent FAO guidance, including the Code of Conduct for Responsible Fisheries It emphasizes the need for setting goals

ard operational objetives for defining shese explicitly as reference points for a range ff fishery indicators; for sdopting decision control rules that inchide precautionary thresholds allowing for uncertainties and isk tolerances, and that drive fishery ‘management using a set of measures tha are pre-agresd with stakeholders Chapter 2 also stresses the aced to integrate use sighs and co-management arrangements into the

‘namsgement framework, where appropiate, as hey clemts for sucess ‘Chapter 3 prosents the process of stock assesment, underlining the need for {quantitative assessment of uncerisnties and risks and the provision of advice based on the various goals ofthe Fishery and considering both short and long-term impacts of sansgement strategies, Methods are given to estimate the surgent status of the Fishery ther as the stock size, the fishing mortality rate or other ecologies) oF gos-based Sndicators Methods are also described foe estimating maximum sustainable yield (MSY) snd other yild-based reference points as wel s some aimed at provsting the spawning capacity ofthe stock and avoiding recrustment overfishing, For sustainable exploitation,

414s recommended that yield-based reference points are use as targets while spassning capacity reference points are used as limits and given the higher preceence, Precautionary thresholds should be set so prevent the limits being exceeded ‘Chapter 4 provides information on the FMSP stack asestment cools and guidelines including four EMSP software packages ~ LFDA, CEDA, Yield and ParFish ~by whish ingcrmediate paramere, indicators and reference points may be estimated The inputs nd outputs and the elative advantages and potential uses ofthe tools are described The

four chapters in Paet 2 further describe these four sofewate tools, residing guidelines ‘om their use and the iting of models, Fell technical details ad svtorias are avail in the software help files provided on the assompanying CD-ROM, Part 3 then summarizes the guidlines produced by a sumber of other FMSP projects relating to stock assessment and management approaches that were iatraduced in “Chat 4, Chapter 19 uses simulation models co compare the performance of length- Insel and age based approaches for two tropical fish spesies The analysis demonsteates the benefits of using age based spproaches where possible, but iis noted chat results may differ for other spevies and their particular lite history strategies Chapter 11 develops simple relationships for che estimation of potential yield and maximum sustainable fishing monaliy based on the Bevercon and Hloe “life-history invariants” “These eclarionships allow sustainable yields and fishing eapacity to be estimaced from sparse data, which may ether be already available, or cxn he relatively easily obtained

Chapter 12 derives g

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‘of empirical modelling approaches that can be used to support Fisheries management, anging in complexity from sinple methods that only require historical catches through to complex multivariate madels based on General Linear Modelling and Bayesian network approaches, These approaches may suit data poor circumstances, or when among fishery comparisons ae possible, for example under adaptive approaches to (€0") "Throughoue the framework, the use of adaptive learning and feedback approaches are promoted within the general principle of precaution Complementary wse of thes approaches should enable incertaintes to be reduced and long-term benefits to be maximized with reduced risks ta the resource base

Hogarth, D.Ds Abeyasekera, S; Arthur, Ril: Beddington, J.Rs Burn, RWG

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Acknowledgements

Part 1 of this document ~ the framework for ssing the FMSP stock assessment tools ~ was crafged around the outputs of various FMSP projects and studies, mainly: by project manager Dan Hoggarth Thanks are due ro Robert Arthus, Ashley Halls, Geoit Kirkwood, Psu! Medley, Chris Mees, Catherine O'Neill ard Graeme Psokes for their help in defining the framework wsed in Part 1 Robert Arthur drafted sections 2.3 and 2.8 and contributed go other parts of Chapters 2 and 5; Graham Pilling drafts section 5.43; Chris Mece drafted section 44 Material for Parts 2 and 3 of the dacument were ‘ost drafted by the original researchers ofthe diferent EMSP project, as listed atthe start of exch section “The authors are grateful to the participants of the September 2004 FMSP Stock Assessment Tools training workshop held in Mangalore, India, for their usful comments ‘onan eatly deft af the document; and wo Job Nuovo, Kevin Stokes and Catherine O'Neil, 5 well as Senge Ganis and Kevern Cochrane of FAO lor ther ets ad soggestions on the ` CREDITS

‘The LFDA and CEDA packages were designed by Dr Geoff Kirkwood Richard Auckland and Simon Holden and programmed by Richard Auckland, Steve Zara, Mark Bravingwon fn Simon Holden “Yield” was designed by Dr Geoff Kirkwood and Trevor Branch ‘sd programmed by Trevor Branch, Simon Nicholson, Steve Zara and Brian Lavoe The Parish softwere wasdesigned and programmed by Paul Melly The Parish toolkit was designed by Pasl Medley, uzaisah Walmsley and Charlotte Howaed

AUTHORS’ ADDRESSES Daniel D.HOGGARTH

‘sch Crefield Road, London W3 9PS, United Kin Ireland

Savitri ABEYASEKERA and Robert W BURN

Statistical Services Centrs, University of Reading, PO Box 240, Reading RG6 GEN, United Kingdom of Grew Brtsin and Northern Ireland

Robert L ARTHUR, Ashley’S HALLS, Christopher C MEES, Graeme B, PARKES and Robert C, WAKEFORD

MRAG Lid, 18 Queen Sacer, London W1] SPN, United Kingdom of Great Britain and Northern Ireland

John R BEDDINGTON Division of Biology, Faculty’ of Life Sciences, lmperial College, South Kensington campus, London SW7 2AZ, United Kingdom of Great Britain and Northern Ireland Geoffrey P KIRKWOOD, Murdoch MeALLISTER and Robin L WELCOMME Renewable Resources Assessment Group (RAG), Imperial College (3 above) Paul MEDLEY

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Contents

Preparation ofthis document iit

‘Abe CC Cơ —————————————k Acknowledgements v

Sgmbol: spd abbrevbvdons xy

PART 1 FRAMEWORK FOR USING THE EMSP STOCK ASSESSMENT TOOLS

Luntraductign 1.1 ‘The new international legal regime 3 1.2 Purpose and content of the quidelines 4 1.3_A framework for fisheries management 5

2 Fishery management systems 9

21 Management approaches 2.11 Comprehensive rational planning 3 3 2.1.2 The precautionary approach 70

2.13 Adaptive management 2

2.2 Management scope 221 Single species management 14 1a 2.22, Multispecies and multigeae management (Gechnical and biological interactions) “

2.2.3 Ecosystem management 5

23_Use rights 231 Aqesriaht 18 19

232 Withdrawal (hanes) lan 19

2.4 Control rights and fisheries co-management 20 2.5_A precautionary management process 725.1 Goals and operational objectives 23 24 2.5.2 Indicators and reference points ~ measuring management performance 77 7 #8 2.53 Harvesting stategies and dedsion contol rules 30 2.5.4 Precautionary reference points — allowing for rik and uncertainiy 3 25.5 Management strategies and measures 35 2,6 The role of stock assessment in management at 3 The stock assessment process 7 31 lnwedugiae 4 4 3.11 Qualitative or quantitative? 4 3.1.2 Deterministic or stochastic allowing for uncertain? 35 5.13 Blomass dynamic or analytical models? +

53:14 Egulbvium or dynamic? +

3-15 Age-based or length-based? a

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22 Collecting fishery data 51

(1.2.2 Size compositions (catch at age and lenath-frequency dete) — — 54 423 Other biological data 8

32.3 Estimating intermediate fishery parameters S31 Geoeth atest occa fabs 35 2.22 Population growth rtm and carina capa s 53.3 Natural morality cate bị 325 Sock and cacutment 336 Beploitaon pattern (gear sleciy) 9 3 57 catchabilty 5 3⁄4 Indicators = measuring the cuzentstaus f the fahery Acai ston and CPUE 60 s8 3á2 takaBe 3A3 Fishing morality at i 2 3g Other nati 35 Estimating technical reference points 35.1 MSY reference points 5 s S52 Proxies for MSY and oer yt based reference pont s 353 Reference point for maintaining the roreduetue aody SĨ een ee 3.54 fik-defined reference pois 7 355 Mullipeces and eccnsten-based rfaence OTS 5 S58 Eeenonie and acl refeence 74 6 Providing management advice 361 Feedback fr “contol ule” management 76 7 1262 Making projections thon tem and medion tam ae 3.63 Recognizing multiple objectives and management options 7 78 35d Proving adc on uncertainty adi = 5 Marogematt proces eration, m

4, The FMSP stock assessment tools and guidelines 35 4.1 Growth and mortality rates from length frequency data

Sine Urba software) 4.1 Purpose and methodology 35 35

4222 Inputs and autputs 26

21.3 Applicability and related approaches $6 42_Reference points from minimal population parameters

“2 fhe Beverton and HOW “invariants” metiogs) 7 4.3 Reference points from yield and biomass models he Vield software) 39

43.1 Purpose and methodology 89

443.2 Inputs and outputs 30

143.3 Applicability and related approaches 3 4.4_Managing fishing effort in multispecies fisheries ‘44.1 Purpose and methodology 9a 94

4.42 Inputs and outputs %

14.43 Applicability ane related approaches % 4:5_ Biomass dựnamiddepletion models (the CEDA software) 445.1 Purpore and methodology 3 ‘7

445.2 Inputs and outputs Tơ

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46 Bayesian stock assessment approaches ‘46.1 Purpose and methodology 107 107 4.6.2 Participatory Fisheries Stock Aarasement he Parish software) '46.3 Comparison with other Bayesian software 110 1H 4L7_ Empiical stock assestment approaches ‘47.1 Predicting vields from resource areas and fishing effort 114 114 47.2 Multivariate modeling of fishery systems 114 4.8 Special approaches for inland fisheries {48.1 Integrated flood management for fisheries and agriculture 115 116 44.82 Stocking models and adaptive management HH

SGondusion tt

PARL2 INTRODUCTORY GUIDES TO THE EMSP STOCK ASSESSMENT SOERNARE,

6 The LFDA software — Length Frequency Data Analysis 197 6.1 Fiting vọn 8ertalanffy growth curves 6.1.1 Fitting seasonal growth curves 127 129 65.1.2 Uncertainty in the LFDA growth parameter imate 130 6.2 Estimating total mortality rates 2) 130

‘Lhe Yield software ts

7.1_ Including parameter uncertainties 133 7.2 Estimating equilibrium per-recruit reference points 133 7.3 Estimating equlibrium yield and biomass reference points 134 7.4 Yield projections and the “risk-based” Transient 558 reference point 135 7.41 Making nan-equilbxium projections under variable recruitment —135 7.42 Estimating the Transient $56 reference point 137 8 The CEDA software ~ Catch Effort Data Analysis 81 The CEDA models 18 139

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9.8 Models fitted to data 98.1 Approach ts 155

9.82, Population models 156

9.8.1 Sock assessment intanieg Tá

99 utility ssinemag———— ah 158

9.92 Prafecence inteniew 188

9293 The catchetion cenatios CC CC CC CC CC T60 9194 scoring 161 29.5 tors and feadbade 286 Preference model tt ac PART 3 OTHER EMSP ANALYSES AND GUIDELINES

10 Comparisons of length- and age-based stock assessment methods 165 Steen eee 10.2.1 Growth parameter etimation 165 10.22" Management strategy simulation 16 fom ` 10.3.1_ Growth parameter estimation TÐ 162

303.2 Management strategy simulation 168 104 Discussing 10.41 Growth parameters 18 169 10.2 Assesement of management performance 169 111 The estimation of potential yield and stock status using Tie history parameters 175

mm ==—

112 Potentialyield ‘U2 Constant recnuiment H8 16 112.2 Recruitment varying with stock wine 379 113 Stockstatus 2.1 Constant eecruitnen a Bi 1132 Recruitment vaying with stock size 184 Ce ILS Assessing stock status 186 1.6 Concluding remarks 186 12 Managing fishing effort in multispecies fisheries 189 lãi Intuadueian a

122 Seme key indings from the study 189 123 Guidelines for data collection and management of multispecies|

i 123.2 Summary of biological guidelines Yor management 191 12.33 Rules of thumb for evaluating the status of kev species and ‘management response 192 13 Bayesian stock assessment of the Namibian orange roughy (Hoplostethus atlanticus) fis 195

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13.2 Namibian orange roughy: biology, exploitation and scientific sean ee a 133 Initiation of the fishery and stock assessment of Namibian ‘orange roughy 196 13.4 The 1999 revised Bayesian stock assessment procedure for Namibian orange roughy 198 13.5 Some key features of this application 200

1a Rewits oe

122 Disassing CC C77777 Mã

14 Empirical modelling approaches 21

14.1 A simple model to predict potential yield from catch time series 211 442 Empirical multispeces yield models 142.1 Models based upon habitat variables 213 213 1422 Models incorporating fishing effort 218 43 Multivariate models .1_The general linear model approach 2 223 1432 Bayesian Network (8N) models 228

——————————— na

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Foreword

Fishery analysts require stock assessment ools to provide advice ro managers but may ‘he constrained in choosing the be tools by the dificult inadentfying the veal benefice and costs of the alternative options This guide attempts to help stock assessment ‘advisors (and in some countries the managers themselves) co choose appropriate tools for their nceds Ie focuses particularly on a suite af products developed by the Fisheries ‘Management Science Programme (FMSP) of the UK Department for International Decelopment (DFID, previously known as ODA) The FMSP was established by: DEID to generate improved livelihood benefits for ‘poor people throsigh the application of new knowledge in bath capture and enhanccrrent fisheries, Since is ereation in 1992, the FMSP has produced a series of outputs on the sssessment and management of exploited fish stocks These outputs range from new methods and software for assessing fish stocks and providing guidance to fishery managers, to applied research on specific country fisheries The first EMSP software packages (LFDA and CEDA) were developed in the early 1990 and have already been used by an estimated 150 fishery scientists in developing countries PMSP projects have Ieee undertaken by many different scientists, usually involving collaborations between United Kingdom and developing country researchers and managers Much of the output hạc slesdy heen disseminated by the individual projets, eg at symposia, in journal papers, via collaborating country fnstiations and sơ cm, Many of the technical reports tnd papers from the projects ar available an the FMSP wc sie (hatel/wwweémsp.org ‘uk/} maintained by the programme manager MRAG Lid “This document attempts to synthesize the various FMSP tools, guidelines and ther foutputs into a single, integrated guide about stock assessment asic eelates to fishery ‘management The materials include in the document originate from over twenty FMSP projects (see list below), our of the total of 48 carried out since 1992, Other FMSP projects have focused on a range of copies including floodplain river and reservoir Fisheries ecalogys fish aggregating devices; economics and management of foreign fheres in Exclusive Esonomne Zones (EEZok prawn Fisheries enhancement; and the understanding of fisheries Hveinoods "The framework presented here integrates the need for precautionary and adaptive ‘management processes and, as suc: is compatible with (and partly derived from) the ‘mansgement framework currently promoted by FAO (FAO, 1997; Coeheane, 20223) ‘Much of the same terminology’ is deliberately adopted Ie is designed to support the new paradigm of precautionary management as described in the Code of Conduct for Responsible Fisheris (FAO, 1995a, 1996) and the 1995 UN “Fish Stocks Agreement”, whish entered into forse in 2001 This guise attempts to faclitare and support the Implementation ofthese instruments by describing she range of possible stock assessment approaches that may be used to feed information into the management process, and by providing some tested tools for their app While attempts are made to deseribe the alternative posible ravtes that stock assessments may follow it x stressed that fish stock assessment is a complex and much sadied field, with many variants of the different models available and in use around the world ‘This manual does not attempr to describe all the possible approaches, but 1 to describe the FMSP tools d

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ferent EMSP sofewarg, included on the companion CD-ROM Itis assumed therefore that readers will have atleast abasic understanding of the alternative stock asessment techniques snd fisheries models and thei opeeation Purthee deals on the mathematics and assumptions behind the diferent methods may be found in fisheries textbooks such 25 Gulland (1983), Hillborn and Walters (1992), Sparre and Venema (1998), Q4 nw and

Deriso (1999) and Cadima (2993)

List of FMSP projects covered in this guide RaBI7 Ra 85030 RS050CH, Reiss 5955 5958 Ret7s R636 Rots? Rotes Rois R700 R704 R702 R703 R75 R524 N7 kre R835 R/97 Ra2lo Raas Ra

Development af Computer Aids or Fish Stock Assessment and Management Poliey Guidelines for harvesting species of different Hfespans

Synthesis of simple predictive models for river fsh yields in major tropical ‘Computer Aids in fish stock assessment ~ Feld development

[Analyse of Multspecies Tropical Fisheries

Fisheries Dynamics of Modified Floodplains in Southern Asia (Culture fisheries assessment methodology

Synthesis of simple predictive models for fisheries in topical lakes

‘The performance of Customary Marine Tenure (CMT) ia the management cof community fishery resources in Melanesia

Management strategies for now or lightly exploited fisheries in developing Growth parameter estimation and the effect of fishing om size composition and growth of snappers and geoupers: implications for management - Phase and IL Evalustion of the biological and socio-economic benefits of enhancement of Aoodplain fisheries

Serategic assessment of tropical coastal fisheries management Sofeware for estimating potential yield under uncertainty

Information systems for ca-management of artisanal fisheries

Selection criteria and co-management guidlines for harvest reserves in tropiel river fisheries Adaptive lesening approaches vo fisheries management

Implementing management guidelines arising from project R6#65 - an assessment of wiity in the BIOT inshore fishery

“The potential for improved management performance with fly age-based stack assessments: Extension of the management stategy simulations to incorporate age-based assessments

Inceeiscipinary multivariate analysis (IMA) for adaptive co-management Investigation of the implicati

fisheries management

of diferent fish Iie history strategies on Integrated fisheries management using Bayesian mul-stterion decision raking

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Symbols and abbreviations

Note: A glossary is not provided with this publication, Readers are instead invited to refer to the glossary given by Cochrane (2002s), which uses meh of the same terminology (sce httpe!/wsw:f40.0rg/DOCREP/005/Y3427E he detailed FAO Fisheries Department glossary is also available a hisp//www:fa, 34270 hemlbm 12), ‘ong/flglossary default asp symbols

2 Coefficient inthe length-weight relationship

In Chapter 11, used asa constant “mokiphier", conditional on ane 6 mote ther parameters, eg aL.) at Lb) b Dower in the lengths weight relationship Biomass

[Biomass at start of exploitation (sometimes assumed equal r0 K) Carrying capacity or unesploited biomass (ue Kas used in PạrEih (Current biomass (as used in chapters 1-3) or current biomass a8 a properties of the unexploited biomass, K (as used in the ParFish chapter 9)

c Catch, ia eumber

© (Oscillation amplizude in seasonal VBGE as used in LEDA,

7 r Fishing effort Instantancous coefficient of fishing morta

Fy Fishing morealiy rae, estimated by methods assuming equilibrium conitions overage and time + Current fishing mortality rate

+ Nest year’s fishing mortality rate

4 “Yield” and Beverton- Hole “invariant” methods Density dependen press in the Beverton and Holt SRR, as used ia & {Growth cate of individual fish, as in che yon Benslanffy growth model K Carrying capacity or unexploted biomass, ain biomass dynamic modes h ‘Total length of an indisidval

1 Smallest length fully represented in sample (in Beverton-HloltZ estimator, used in LFDA, et); mean length a frst captace in *Yield” k Kale-edged length a fest caprure, asa proportion of 36 used in “Heverton-Hole iwvarianes” methods (in Section 4.2, Chapter 11) L Length at which 89 percent af ish are eapeured (lected) by the fishery (in Chapters 19 and 11) 1 E ‘Mean length at maturity as used Kote edged length at fist maturity, asa proportion of L., 38 wed in in "Yield

‘Beverton-Hole invariants” methods (in Section 4.2, Chapter 11), Lov Length at which 39 percent of fish reach first maturity Asymptotic length towards which fish grow, according to the VEGF

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w x ; Zz

Statistical coefficient of determination or R-squated) Recruitment to the exploitable phase

Replacement yield, that would maintain stock sie at its current lew as estimated by CEDA Stack size (numbers or biomass)

Age (usually measured rowing species) in years, but may’ be days oF weeks fo fst ‘Mean age at frst capture, in “Yield”

‘Age at which 59 percent of fsk are capture (selected) by the Fishery (in Chapter 10)

“Mean age maturity, in "Yild”

“Ambient temperate in the Pauly (1980) natural mortality equation “Theoretical age (1) at 2eroTeogth seeordimg to the VBGF Winter point in seasonal VIGE

Individual weight

Proportional escapement (in ection 4.8.3) Yield or catch in weight

Instantancous coefficient of total mortality

Shape parameter in Pella“Tomlioson DRP model used in CEDA, ‘Technical reference points Bạc oan) F MBAL MEY MSY đu,

Biomass ar the lowest historically observed spawning stock size [Binmase that would produce the MSY

F at which te slope of the YR curse is 10 persent ofits slope at the otigin also Fis, Fy et)

F that reduces SPR to the specified percentage of is level in at unfished sock Ƒ thất reduces SSB to the specified percentage of its level in an unfshed stock as estimated in “Yield”

F that reduces the fishable biomass (FB) co the specified percentage ofits level in an unfished stock, as estimated in “Yield” “The point an an equilibrium yield curve at which both the biomass snd the catches are reduced to 2era

F associated with the lowest historically observed spawning tock sire Like Fas the F corresponding to the 10° percentile ofthe observed points Like Fu the Feorresponding tothe 99° percentile ofthe observed points E giving the maxionuin YDR in a dynamic pool model (also Fao) ia (Chapter 11, Fou as used inthe variable recruitment models equivalent to

đạn

F cortesponding to 2 SSB/R equal ta the inverse of the 50" percentile of the observed R/SSB {in Section 3.5.3)

F that would prosluce the MSY corresponding tothe slope ofthe SRR she origin (equivalent Fa) E giving a specified probability that che %SSB wil fll below a specified level during forward projection of x years, as predicted by the "Yield” sofiware

Minimum biologically acceptable evel, of spawning stack size, required to void recruitment overfishing, as observe in ploss of SR data Maximum economic yield

Maxim sustainable yield

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Conceptual reference points (used in defining control rule frameworks) By, Biomass associated with the [RP

Là Precautionary biomass reference point, usualy set above Bl, according 0 measured uncertainty and agreed risk tolerance (equivalent to NAFO's By and ICCATS Bụ„.)

Ba Fishing mortality rate assosised with the LRP

Dã Precautionary fishing morality reference poin, usually set below Fin sccording to measured uncertainty and agreed risk tolerance LRP Limit reference point

PRP Pecsudonuy celerence point TRE Target reference point

Other abbreviations

BPR Biomass per recruit

CBD Convention on Biological Diversity

CCAMLR Commission for the Conservation of Antarctie Marine Living Resouroes CEDA a DAD DRP ELEFAN ESATH EMSP IccaT ICES ICLARM OA, trọ wu EEDA MEY MPA MSY NAO Parish

EMSP Catch and Effore Data Analysis sofeware

‘Confidence interval Department for Intemational Development of the UK government Deterministic reeuitment/production models, e.g Schaefer, Fox mouels ‘etc, a8 fitted in CEDA software Pauly’s (1987) length-based growth rate estimator as used in LEDA,

ESAT, ete

PAO-ICLARM stock assessment cools software Fisheries Management Science Programme of DFID

International Commission for the Conservation ofthe Atlantic Tuas International Counel for the Exploitation of the Sea

International Center for Living Aquatic Resources Management International Plans of Action

Individual eransferable quota (he right t share of an annual catch quota) leg, Unreported and Unregulated Fishing

FMSP Length Frequency Distribution Analysis software Maximum Economic Yield

Marine Protected Ares Maximum Sustainable Yield

Northwest Atantic Fisheries Organization

FMSP Participatory Fisheries stock assesment software PROJMAT Projection matrix method of fising VBGE, a used in LEDA SLCA SRR 5B SSBPR SPR SPR TẠC ‘TURF UNCED UNCLOS VBGE VPA 'WSSD YPR Shepherd's length camposiion analysis se wsed in LFDA Stock-reeruitment relationship

Spawning stock biomass

Spawning stock biomass per eecruit (or SSB/R) Spawning products per recruit

SPR as a percentage ofthe level that would accur in an unfished stock Total allowable catch “ervitoral use rights in fisheries

United Nations Conference on Environment and Development United Nations Convention on the Lave of the Sea

von Bertalantfy groweh function Virwal population analysis

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Part 1

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1 Introduction

1,1 The new international legal regime

Mos fisheries books seem to begin with an account of the poor state of the world’s Fish resources, There are certainly plemty of fisheries that are overexploted, many that are achieving less than thie maximum potential and some thst have collapsed outright ‘There ae also, however, sherie thạc cemain healthy and productive, some perhaps by Tuck, bu oxhers by design, While fisheries management can be succesful this will surely only be maintained over the long term where clear management policies are implemented by a proactive management process Where fishery managers ate Uunawate of che status and potential of the esourees under ther responsibilty, they are unlikely to act at the right time or to make the right choices A suite of international instruments is now in place that promotes effective management action inal fisheries, regardless of their size and stution Diflerent strategies and approaches will work indifferent places but the requirement of good governance forall is now Grmly established ‘The eal bass forthe management of fisheries was ested in 1982 with the agreement of the UN Conseation on.the Law ofthe Sea (UNCLOS), Recogeizing the ned for international coordination for the management of straddling sed highly migratory fish stocks, the UN “Fish Stacks Autcemeat” wa signed in 1998 This requires states to cooperate in managing fishery resources both within and beyond theie exclusive economic zones The 199 EAO “Compliance Agrccmem” addressed the problems associated with reflagsing of fishing vessels as 4 means of avoiding conservation and rmanagersent rules onthe high seas (Cochrane, 2062b) Both UNCLOS and these rwo legal extensions to it are now in force and binding on those counties that have signed and/or ratified chem

Tn addition 10 these legal instruments, several non-binding guides have been developed to asst states in building good! management practices Chef among these is the FAO Code of Condust far Responsible Fisheries, also finalized in 1995 (FAO, 1998s) This moves from the single-state, single species, MSY-based focus of UNCLOS into ecosystem management and the preeautonary approach (de Fontaubert and Lutchman, 2003) The intentions of the Code are elaborated by the FAO Technical Guidelines for Responsible Fisheries In particulae, Guideline No 2 deals with the precautionary approach to esprure fisheries and species introductions (FAO, 1996, Also 1995bs see Section 21.2} No.4 (published in two volumes) adresses the Eenerl process of fisheries management (FAO, 1992), Caddy’ (1996) provides 3 checklist of fishery management issues seen from the perspective of the Cade of Conduct Within the framework of che Code of Conduct are the four current FAO

jatenational Plans af Action POA) have been developed These cover the ection of incidental catches of seabirds in longline fisheties; the conservation and management of ack the management of fishing capacity an the prevention of egal ans/untegulated (1UU fishing National legislation forthe formal implementation of unespavted

these plans is now being developed in many counts ‘Beyond the national level, mose parts ofthe world’s oceans are now covered by one lor more regional eates, commissions or fisheries management organizations Only some ofthese have powers to set management measures that ae binding onthe Fishing fleets of their member countries; many have only advisory functions (de Fontaubert and Lurchman, 2008), None has fully-<ffectve enforcement capabilities, beyond the control exercised by flag states

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sssomen fo hor managomen

[Aca beoader level, the legally binding 1992 Conssation on Biological Diversity (CBD) provides guidance onthe conservation, sustainable use, and equitable sharing of the benefit of biodiversity Chapter 17 of the United Nations Confrence on Envjonment and Deselopmen’s (INCEDL Sgenia 2 and the werk programme of the CBD's 198 Jaharta Mandate provide for the protection ofthe oceans, ea, and coastal areas At the ten-year review of UNCED in 2002, the Johamnesborg War Surnmit on Systinable Deselapment QWSSD) agreed 3 pln to “msintain or restore ish] stocks tolevels that ean produce te maximum sustainable yield where possible nĩi sterthạn 2013740 "exabish effective monitoring, reporting nd enforcement, and onirol of fisbing vessels; 10 “climinate subsidies that soneibute to IUU Fishing"; and to etablsh “representative networks” of matine protected arexs by 2012

‘With this legal and advisory regime in place, there is surely no lack of targets for states to work towards nor any lack of guidelines om how they may be achieved More than ever beloge, coastal states are being called upon to focus intensively on fisheries management 10 secure the future of their fish resources and Fishing industries Some argue tha the profusion of legal instruments may overwhelm small sates with lnited fonding and capacity The need to simoleancously achieve both fisheries development and cosystem management goals presents challenges in toring all ofthe diferent concepts and guidelines inco achievable operational abjetives (Garcia al, 2503) Solutions tan be found, however, by Keeping, clear focus on the resource hase of sustainable development (see Section 25.1), According to the FAO Web site as of Jane 2008, 82 ‘countries reported having fisheries management plans in place that incorporate elements of the Cade of Conduct, including measures to promote use of selective fishing gear, to prohibit destructive practices, and to ensure chat permed catch levels reflec the state 5f stacks and allow depleted populations to recover The pace of uptake varies greatly berveen counties, bur many states sill need to put effective frameworks in place Much remains to be done then, particularly for smal scale, arssanal fisheries These sre reported by FAO 5 producing about 50 percent of the world capruce fisheries |narvet thats sed for human constmption, and s employing abot 20 millon fishers swith many more in downstream, fishery-rlated jobs These fisheries require more ‘tansparent involvement of sakeholders in the development of fishery management plans; the decentralization of decision making: nd the coordination of inte-scetoral linkages between fisheries and the wider social snd ecological systems All fisheries require responsible management now to sustain their prential benefits to society

4.2 Purpose and content of the guidelines

Fishery managers in both developing and developed countries are usually required to achieve poliey goals aimed ar sustainable production of fish yields forthe benefic of sher livelihoods, national food security and economic gain Many different stock assessment models and software packages are avilable to assist managers in reaching these ouls These tools range from simple techniques for estimating parameters such a growth and morality rates, to full simulation models of fishery systems allowing inmeractions between different species, fleets and gear types, and predicting the effects of different management strategies The requirements of such cools, particularly the

data inputs, vary greatly Different tools are also applicable to diflerent fisheries, depending on their operstional structure, ecology and the intended management strategy Fishery managers need o select and use appropriate decision-making support tools from he wide eange of possible choices, bearing in mind ther capacity to collect the accessary data and ther ability to use the models and implement che management xuidance produced Finding the best rool, however, can be hampered by the diversity ‘of choices avilable and the dificuley of comparing the costs (input sequieemenss) nd

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troduction

bengfis (type and precision of management advice) of each tool, As a result, many fisheries in developing countries are either nor managed, of ate managed with only nominal regulations and withoue any zal assessment of the status of fish stocks Such countries 13k losing the many benefits availabe from their resources, This guide attempts to help fishery managers and ther stack assessment advisors ta choose decision-making support tools that will be appropriate to their circumstances and that will produce outputs that support responsible use of fishery resources, recognizing the need for a precautionary approach in the fave of uncertainty The guide tocuses particularly on four software tools ~ LFDA, CEDA, Yield and ParFish ~ developed by the FMSP, but also makes reference to other guidance and tools developed both by the FMSP and elsewhere Such tools are placed ina framework for fishery management and a related process for stock assessment These are described in Chapters 2 and 3 respectively, and summarized in the following Setion 1.3 Chapter 4 provides summary deuails on the msin EMSP tools, concentrating on their main objectives, their data inputs and outputs and their relevance to particular circumstances, Pare 2 presents further deals about the software tools and Part 3 describes other FMSP analyses and guidelines Previous FAO stock assessmeat maswals for tropical fish stack assessment (Sparre Ursin and Venema, 1989, and Sparre and Venema, 1998) have focused mainly on length based approaches, Both these manvals and that of Cadima (2003) have paid Taniced attention to the uncertainey inherent in fish stock assessment and the now widely recognized need for precaution indecision making (see below) This stock assessment manual takes a diferent approach, giving less detailed coverage of the mathematical background ofthe different tools already well covered in the mana above-cied, snd in textbooks suchas Hilborn and Walters, 1992, Quinn and Deriso, 1999, nd Haddon, 2001), and paying more attention instead to the estimation of uncertainty in parameters and is subsequent use i the decision making process (Other software packages for tock assessment have of course been produced outside the FMSP, including the commonly used FAO/ICLARM FISAT II software Most fishery analysts will alse have cheir own simple spreadsheets for modelling yild-per- recruit or other fishery indicators The FMSP tools described here are believed to provide significant benefits aver most such alternatives, Advantages inchide the use of non-equilibrium fitting methods and the inclusion of stock-recruit relationships and parameter uncersainty inthe model inputs Al ofthe FMSP software packages are also now very well documented with their own help files and tutorhis, illustrating step by sep analyses of different example datasets, The introductions in Part 2 ofthis guide are ‘essentially shortened versions ofthe software help files During the more than 10 years since their fist development, LFDA and CEDA have beca well tested by many users ina wide variety of fisheries around the world, The current versions of these packages hhave been developed after extensive feedback Icom users i the feld Use of the FMSP software should therefore increase the likellhood of fishery analysts providing good and timely advice to their managers especially when they do not have the necessary background and resources to develop complex programming tools themselves

13 framework for fisheries management

‘This section outlines a comprehensive framework for fisheries management ~ including stock asessment ~ which sets the stage fr th application of the FMSP and other stock assessment tools, complete fishery management system must recognize a wide range of influences that affect the interaction between the fishery, its stakeholders, and the aquatic environment, The system adopeed for each fishery must be well adapted to the specific conditions found at that location, “The main components of a modera fishery management framework ae illustrated in Figure 1-1 Governing the process, ad hence atthe head of the framework is the

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Ireroducon

‘Chapters 2 and 3 of this document describe in detail the component parts of the management framework and the stock assessment process Readers unfamiliar with the concepts and methodologies in Figure 11 should refer ro the sections indicated to provide the necessary level of understanding for informed use of the FMSP stock assessment tools The FMSP tools themselves are introduced in Chapter 4, with ditional details provided in Parts 2 and 3 Figure 1.2 expands on the stock assessment and research bos in Figure 1.1 giving ‘examples ofthe different elements in the stock assessment process As shown in the figure, the FMSP and other standaed stock assessment tools use fisheries data wo assist, inthe estimation of iermediate parameters fishery indicators and/or reference points ‘Management advice is then wvally based on the relative values of the Fishery indicators

and the reference points as described in detail in Section 2.3, ume 12 Examples of the diferent elements inthe stock astssment process outined in chapter 3, ‘Showing the genera low of information towards the provision of managernent advice Pooh nen baial ee Tre 4 _—nemedaupuaneer cannon sac =— 5 FN

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ck aseent for ery management Summary of the ateratve outputs provided by th four FMSP software tools

Gee Chapters 3 and for deta of methods and notation ete)

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2 Fishery management systems

A fishery management system comprises a wide array of activities designed to easure the sational and responsible use of living mavine resources These activities may include governance arrangements (policy, legal instruments, use sights, contra systems ete, management procedures (setting objectives, control rules, performance measures, feference point te), seienifc advice stock sessment methods, management scenario modelling et.) compliance (surveillance and enforcement, voluntary codes, incentive structures etc} and monitoring This chapter provides the background and context for fisheries stock assessment, by fist considering these overall aspects of the management system Section 2.1 describes the concepts of precautionary and adaptive management, both of which are resommended as fundamental foundations for successful fishery ‘management under conditions of uncertaincy Section 2.2 describes the potential range in the scope of fishery management, from relatively straightforward assessments, of single gear, single species fisheries, through consideration of basic technical and biological interactions becveen gears and species, to the notion of a fully fledged ecosystem approach to fisheries, Seations 2.3 and 2-4 outline che range and importance of alternative use rights in fisheries, andthe options for participatory decision making fo cormanagement Considering these varios elements of the management system, Section 25 outlines the steps involved in a precautionary management process

2.1 MANAGEMENT APPROACHES The question of how fisheries ean best he managed to generate benefits for both current and future generations fas been the subject of debate for many years The question is hard to answer because fishery managers face many uncertainties in the state and the dynamics of both the living resources and fisheries under their responsibility Uncereaingy’ in fisheries has many sources Firstly, fish stock sizes and distributions can fMuotsate widely even in their natural, unexploited stats, due to variations in ‘environmental and climatic facts, and the effects of other species with which they lnceract (sce examples in Hilborn and Walters, 1992) In such a variable environment, the Jong sem unexpfoited average stack size will alvays be hard to estimate, especially when changes go beyond random Muctuations in recruitment to signficane episodic “regime shifts" in the siructare of the eeosystem Secondly, aditonal wncertainty arses because stock status ean be estimated with only Fimited precision Inthe case of the northern cod, retrospective analysis has indicated that stock abundance estimates may have been off bby up 10 109 percent (Hilborn,Pikitch and Francis, 1993) Finally, fisheries systems are often excremely complex, involving dynamic interactions within and between the living resources and the people whe utilize and manage them These imterations are only partly understood, if at all, making predictions and management decisions difficult Facing these many uncertainties, managers of natural resources (neluding fisheries) may the three broad approaches towards decision-making: comprehensive rational planning, precautionary management, or adaptive management, Each approach may Ihave its place, depending on the choice ofthe manager, and on the level of uncertainty associated with the resource system The origins and basis of these systems are eseribed briefly below

2.1.1 Comprehensive rational planning

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Siok sient for fiery management resouioe system can be achieved that can lead to effective management and control (aitchel, 1997), Research is believed to provide bes estimates of stock parameters or ‘hese practice guidelines that can then he used by resource managers for managing the resoinee, In the case ofthe simple reference point MSY, researchers can wse the data fram the fishery on yields and fishing efore to estimase MSY and the corresponding level of fishing effort sequired vo achieve it, and sis can then be used asthe eanagemient target

Comprshensive rational planning daes not generally begin with an assessment of existing uncertainty nr an acceptance that it may not be possi understanding ofthe fishery system and the species affected by it This typeof approach

10 achieve sufficient

is therefore best suited 10 conditions of low oF no uncertain, Wheve considerable lancer exists, a8 in fsberes, believing dat decisions can he made with complete ‘confidence is ikely to resul in disappointment

2.1.2 The precautionary approach ue toies failure to acount for uncertainty, “comprehensive rational planning” bas led to some nasty stirprises for fishery’ managers with stock collapses ani socal disruption, Scientists and managers are now aware thatthe precision of fishery assessments is lower than once thought, that fish populations ate less cesilent than onee imagised, and thar the secovery of populations once depleted can be much slower than expected (Hilborn, Pikitch snd Francis, 1993; Staples, 1996: and Pkitch, 2092), While pelagic sacks tend to recover quite well when fishing is redoced, longer lived and slower growing demersal stocks may not recover within 10-20 yeas, The northern cod stocks SH Newloundland, for evampleate sill showing lite sige of recovery despite a nearly complete closuse of the fishery since 1992, Vakuable fisheries clearly may crash

wer heey exploitation, and sientists have only a imsited understanding of the processes that govern recovery (Royal Society, 2003), This change in perception concerning the resilience of natural resource systems has also altered the view of how they should be managed Building on the 1992 UNCED

meting ia Rio de Janeiro, the FAO has vigorously promoted the concept of the preciutionary approach to Fisheries management, ivan attempt to avoid undesirable foutcomes Precautionary management is atthe care of both the UN “Fish Stocks ‘Aarcement” (i force and binding on signatories since 2001), and the FAO Code of (Conduct for Responsible Fisheries (1953) The Code of Conduct advises tha 75.1 States should apply the precautionary approach widely to conservation,

management and exploitation of licene aquatic resoarces in andr to protect them and prewroe the aquatic environment The absence of adequate scentifc information should not be need as a reason for posponing or failing ta take conservation and managennent measures 75.2 In implementing the precautionary approach, States should take into account, intr ali, wncoreaintios relating tothe size and praduatvity ofthe socks, reference ‘points stock condition in relation to such reference points, levels and distin Of fishing moreality and the inapactofFiubing acticties, nclding discard, om non-target and asociated or dopendene species, well as environmental and

scio-economic conditions

An explasition of FAO's interpeetation of the precautionary approach was given in Annes Il of the Fish Stocks Agreement (soe Section 3.5) Further elaboration was provided by the FAO Teshsical Consultation on the Precautionary Approach 10 ‘Capture Fisheries held jn Lysekil, Sweden in 1993 (EAO, 19980, republished in 1996 ss Paper 2 inthe Technical Guidelines lor Responsible Fisheries series), Revogaizing that uncertainty pervades fisheries management and complicates informed decision-making, the precautionary approach says “the greater the "uncertainty, the more conservative should he the approach” (Cochrane, 2032) Where

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a Seomprchensive ational plannes” might aim exactly at seutng fishing effort or quotas to achieve the model-predicted MSY, 4 precautionary manager would reduce the eifor, for quotas aceording to the level of uncertainty with which the MSY’ is estimated, In a well-managed fishery with an expensive monitoring and analysis system, this ‘precautionary MSY" might be quite close ro the model-predicted MSY Ina data-pooe fisher; it should be much lower, ifthe fishery to keep on the safe side ‘The precautionary approach alo proposes 4 shift in the burden of proof from the regulators ta the exploiters of the resource, Would-be exploiters nced thus show that their activities will aot result in undesirable outcomes for the ecosystem and environment, rather than such outcomes having to become evident before management action is taken to control them With this shift io the burden of proof, the ineentive forthe fishing industry to reduce uncersinty should be strong, High uncertangy calls fora high degree of caution, which in fisheries terms means lower catch levels Bester data strengthen the scientific asis for managensent, ana thereby reduce uncertainty and the magnitude of any “precauionary buffers” (Dayton, Thrush and Coleman, 2003), Providing good data and working with managers showld in theory mean thatthe industry will he allowed to catch more fish, "The precautionary approach goes well heyond just setting catch limits The FA Guidelines (1996) delineate a comprehensive precautionary approach to fisheries a8 a whole, addressing the sources of wncertsinty (ind risk) inall aspects ofthe progustion and management process in esearch (and the elaboration of advice), management (and decision-making), monitoring (and performance assessment), conteol and surveillance (cracking and correting deficiencies inthe system) and in operations eedcing the risks ‘of accidental impact ta species and habitats) Mace and Gabriel (1999) have argued that the concept of precaution has become overused and that what is relly needed is relevant and informative esearch, and effertive monitoring and enforsement According 10 them itis really yanuagement that should he precautionary ein educing the quotat0 75 perceat or 80 pervent of the estimated MSY according to the uncertaingy in the assessment FAO contends (Gates, pers com.) shit the capacity of management te prevent, rshice oF mitigate onwanted outcomes depends on the precautionary perlormance of each of the sub-processes mentioned above Uncertain fishery oF biological data, poor risk assessment (eg using simplistic assessment methous), incomplete advice, inadequate tsk commulniestion, non-transparent decision-making ancl weak enforcement al have the capacity ta redice the precautionary performance fof management no matter how precautionary are the management objectives and felated reference points (se

approach, as recommended by the experts wo developed the FAC (1996) guidelines In such an approach, reeateh will be relevant and sformative and enlorcement will be effective (as qualified by Mace and Gabriel) ifthe risks crested by uncertaime, erors

‘or corruption are systematically tracked! and quantified, and conveyed tothe decision: makers

tion 2.5.2), Hence the need for a more comprehensive

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Stock sent for mang 2.13 Adaptive management Although precautionary management is now being promoted by FAQ as the new fisheries paradigm tha wil ubstandaly reduce the chances of overexplotation of fish stocks, it ends to provide lite information about the system being managed Since the "MSY" ofa fishery cannot be predicted well unt it has been execeded, too mich precaution may result in a ishery falling shoe of its true potential with managers never really knossing what might have been Overly precastionary management policies may thas limit opportunites to increase knowledge about the system that could improve the management poliey in the long-term, Toovercomethis potential drawback, “adaptive management” may be used alongside the precautionary approach, Adaptive management attempts to reduce uncertsintics over time in a structured process of “learning by doing” (Walters and Hllbora, 1978) Management ations are used or interpreted as experiments to learn more about the resource system at the same time as its being managed New knowledge is generated

by the deliberate use of learning processes instead of sticking ta rigid technical solutions that may be sub-optimal “There are twa main types of adaptive management, passive and ative, bath of which are based on inceeasing understanding and using the results to adjuse management polier + Passive adaptive management adopts the bes iting model for that year, and only updates management policy in future according to new in exch year as “rue” data cha arse naturally Passive adaptive management can make use of existing ‘variation in the resource syste

inorder to provide an experiment Learning may also be guined throvgh temporal and spatial variation arising from both changing rescvre assessments, and natural saration in the resource system (Walters and Filborn, 1978), This type of adaptive management has the grestest potential in resource systems that have a high degree of natural variation, In less variable systems itis posible ro become stuck ina narrow range of parameter space Active adaptive management attempts to produce better information for the long term management of the resource, Tt uses management actions to deliberately disturb the system in “probing” experiments that are designed to enable scientists and other stakeholders co leatn mote quickly about the system and its dymamics The advantage of ative adaptive management is that managers can use management ations to test conflising hypotheses relating tothe resource systen> (MoLain and Lee, 1996) Management decisions may also take into consideration the need to minimize short-term losses and prevent long-term overfishing ~ key

someerns a industry and managers

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‘ikery management tem

fishers can be persuaded or induced to Fish in deliberate experimental patter, the best information resurns may be achieved feom rotational “crossover” designs that inchade different levels of fishing in different areas (Le with replication) and with some control units to show the natutal ehanges in the systems inthe absence of fishing (Hilborn and Walters, 1992; McAlister and Peterman, 1992) While some of the 2teas might be deliberately pushed to find the limits to exploitation, che less fished and ‘canteol areas (refuges) can provide s valuable buffer against possible overexplitation tlsewhere sce eg Leaman and Stanley, 1993), The answers equived of management ould potentially be found much more quickly with such experiments thar with the more usval “one way trip” fishery development where all aeas are equally exploited {see Section 45.3) ‘Adaptive management may work best in spatially structured inshore or inland stocks than in the larger offshore unit stocks Inland fisheries in reservoirs, small water bodies or diserete floodplain river units (Lorenzen et aly 1998; Hoggarth etal, 199% Garaway, Lorenzen and Chamsingh, 2091), or relatively sedentary coastal resources such at lobster or abalone living in reels and bays may be effectively spit up into small vit stocks, either completely or partially isolated from other resource units Such units provide excellent opportunities for good experimental designs using replication and tandomization, Even simple spatial comparisons may help to aeclerate the adaptive learning process, particularly where significant spaval variation in Fishing elfort or ‘ther inputs exists (se Section 14.22) Frameworks to guide the implementation of adaptive co-management approaches were developed by FMSP project R7335 (Garaway and Arthur, 2002) vsing the example of spatially dispersed small waterbody fisheries in Lao PDR Earlier FMSP projects (ammarized in Hoggarth et al, 1999) desribed ingttudonal frameworks suitable for adaptive co-management in floodplsin river fisheries Project R7834 also developed rmukivariate analysis tools that provide statistical advice on how to build models of

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co-management performance (equity, sustainability, compliance, yield etc) hased upon multiiseipinary (ecological, socio-economic, institutional, et} variables Such touls may accelerate the learning process for adaptive management, where capacity for thei use exists (see Sestion 4.7.2), For the large, offshore, lessdifferetated and! more mobile unit stocks, spatil “lock design” srategies may be lese applicable Although temporal replication with interspersion” of treatments (e alternating periods with small and large quotas, ee MeAlister and Peterman, 1992) may give some beneits, managers of such stocks may reed to accep more long-term uncersingy and balance the risks of overfishing withthe

possibilty of missing the highest yiekls Large unit stocks are less amenable vo adaptive ‘management than smaller spatially subdivisible ones sv the risks asscisted with probing are greats, ad there will always be considerable uncerainy in the advice provided (and hence the need for precaution),

2.2 MANAGEMENT SCOPE

22.1 Single species management The traditional paradigin of fishery management is that che productivity ofa stock? is

fundsmentally 2 propery ofits size and reproductive potential and that managers only ‘need to control ishing activities in ways that maintain the size ofthe stock and protect breeding fish 20 achieve a good yield, Unfortunately, most fish stocks share their waters with many other fsh species, of different sizes and life histories, and are caught by a range of liffeent fishing vessels and gears, Applying the optimum single species ‘management controls forall species and gears atthe same time is usually impossible, nd some compromises need to be made Neverthless the assessment and management ‘of unit stocks of single fish spevies ean protide a good start for considering management setions even for complex ecosystems When applied propery, these methods have proven invaluable in successully managing 2 number of fisheries They are likely t0 Femain the best tools for assessing many fisheries based on one oF a few main target species for many’ years Most of the semainder of this guide is thevefore devared xo

single spesies assessment techniques, Where stocks interact with other species and fleets, oF with the sider environment in various ways (sce below), some compromises or adjustments will also need to be made a described below:

2.2.2 Multispecies and multigear management (technical and biologicat interactions)

Neatly al fishing grounds are occupicd by several different fish species tha are fished by several differen types of fishing gear and fishing vessels These fish and fisheries ray interst with each other in varios ways, “Techical interactions" between fishing gears cxst wherever tw or more gears anit vessels operate within the save space, of sth fish from the same stocks of ene ot more species of fish “Biologial interactions” berween fish species ave essentially independent ofthe fishery although they may be affected hy the results of ineeased mortality) and include predator/prey eelavionships

and competition for food, habitats or space “Technical interactions between fishing geats may cither be “direct” oF “sequential” (Hoggan and Kirkswood, 199) In the first case, the gears compete for the same fish athe same time; in the second case, one gear catches fish before they become available co the other, ther due tothe different selectivities of the gears arto the locations or tims that they’ are fished, Technica interactions are often the cause of problems with

Fishery managers oly sn 1 work with the Canam fe pei, ving she nme sock parameter nd inhabng of sunt sock, defined 36“ goup of 2 pata geogrpbicel sie (Spee, Uren and Vena 198 ee aula, 19), Te wt stoke

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Fshery management sites

bycatches" and "discards", Where such discards reduce the catches salable in other fisheries (3 with prawn tra Fisheries where the disesds inelude the juveniles of large fish spesies caught clsewhers), technical interactions can be very important, Other cxamples are given by Caddy snd Mahon (1995) ‘Although technica interactions add to the complexity of a stock assessment, they can sill be handled relatively easily (sce Section 44) Extensions to yield per recruit (YPR) models for example can estimate the likely impacts of management measures such gs gear bans lfort changes or closed seasons, on the potential yields ofeach fish species in cach fishing gear Biological interactions on the other hand are lar more challenging, While it nay be intuitively obvious that 2 helthy stock of some prey species should contribute t0 ‘maintaining the sustainability of one ofits predator spevies, the setal prey stock sizes required are hard to predict or manage Althenh 3 range of theoretical tuc can bệ, ‘made (eg, sce summary in Hillorn and Walters, 1992), the dat requirements of food ‘web and trophic level models such 35 Ecopath with Eenim (Christensen, Walters and Pauly, 2004) ae invariably high, The high level of neertainty inherent in the òtphtx from such models must alsa be carefully taken into account by decision makers, “Taking common-sense precautionary measures, eg that make nominal allowances for biological interactions while stil derived feom separate single species assessments for each species, ot lamping species together for an aggregated modelling approach may sill he the best general statepies for these siuations In setting goals for mulkispeces fisheries, managers should also be awace that prolonged fishing at unsustainable levels ca result in eatch compositions shifting from lange, slower tamnover, more valuable species to smaller, aster turnover, ess valuable species This effect, known as “Fishing đoạn the food chain” (Pauly etal, 1998), ‘cers due to both evonomic and biolegiesl factors Cochrane (2002h) notes that in ‘molispcies fisheries, i will be impossible eo maximize or optimise the yield from all fish species simultaneously, Realistic gosls and objectives mut therefore he established (see Section 2.5.1 below),

2.23 Ecosystem management Moving beyond the mulkispecies scale, fisheries also interact with a number of aon Iharvested species and with mankind's other uses of the natural envioamtene at an scosystem scale, Although some fisheries operate far offshore and away from other Thuman acivitcs, most of the world’s fisheries are in coastal waters where interactions ‘with other users are an important consideration and frequently a constraint Other uses ‘of the aquatic environment can include transport, tourism, conservation, oil and gas extraction, offshore mining and shipping, and aguaculwre (Cochrane, 2002), Fisheres management should take account of the elfests that these other sectors can have on Fishing and also of the converse effects that Fishing may’ have upon them “The “Ecosystem Approach” sims to consider all significant interactions between species, sectors and the wider environment Garcia ef 2008) angue that the now rich set of international agreements relating to ecosystem management (including UNCED’ Agenda 2, the Convention on Brologieal Diversity, the Jakarta mandate, the FAO Cole of Conduct for Responsible Fishing, ets ~ see Section 1.1) provide both a fundamental guidance and a significant challenge for the implementation of theceosystem approach, The challenge imo operational objectives and ecosystem management plans that incorporate isin turning all these principles and goidelines Fisheries Broadly speaking, the ecosystem approach implies 4 more holistic approach to management siming 10 ensure that flors and fauna are maintained at viable levels in ‘their native habitas and that the inceprty of ecosystems is maimnaned as lar as possible “while supporting sustainable levels of human use (Grumbine, 1994),

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to the FAO Guidelines on Fisheries Management (FAO, 1997), but provide the broader perspective needed for 2 sectoral and holistic approach to sustainability in fisheries

The role Marine protected arcas (MPAs) or other forms of reserves are actively promoted by of MPAs ‘conservation NGOs as central elements of biodiversity and ecosystem management ‘The selative benefits of reserves as fisheries management tools, however, i stil 3 subject of mach current debate (see eg Hilborn etal, 2004) The effectiveness of reserve for conservation purposes will depend on the relationship between the reserve size and desig, the natural spatial structure and connectivity, and dispersal rates ofthe populations Stadies have generally shown that MPAs will increase the fish abundances tnd sizes insde the reerve In terms oftheir benefit to fishing, simulation studies have shown they may have lee overall impact on the average yield fom a fishery, bt that reserves should help increase the likelihood of sustainability of the stock, and thus of the fishery The impacts on fishers will also depend on the locations of reserves relative ta fishing por and open fishing grounds, (On their own, MPAs will noc help fisheries if excess fishing capacity is simply isplaced ro fishing grounds outside the reserve, MPAs should thus be embedded withia wider marine management strategies MPAs may be mosesuccessfel at protecting and rebuilding the biomass of the more sedentary species, that can then sustain the Fishery outside the reserve by exporting juveniles oF adults Although migratory species may not benefit much from the local eduction in fishing mortality caused by an (MPA, carefully placed MPAs could sill help some of these species by rebuilding the ‘complexity of habitats that have been destroyed by damaging gears such as crawling, ‘of by decreasing the morcaliy of thee juveniies (Pauly etal, 2002) ‘A balanced perspective on MPAs is offered by the monthly electronic bulletin “MPA News” Issue aumber 48 (Vol 5, ne 6), for example, leads with an article bout balancing conservation and fisheries goals, aiming for the “win-win” solution This describes the potential use of decision-support tools such as MARXANG' that can ‘Summary comments onthe alternative posible scope o scale af sheris management and assessments (se alo Secon 84)

TH HH” — AfmuSu/wwaten advantages omens

Sie pes Simaires des oman bry Ta an —— ya toot open Slogan ni, ‘atipesee rEg cata a main apecirin > Anaad ‘iy imac wh ul Bala al sop

“Asin ans to Bt bch, + Matto optinze como fo al pes dra se timers ned Scop tone

++ Use aggregated blomass dynamic eae

po a

Ribas ana cco tances” "yersoul mova lense — - Ặ- neo bí Hướn zrrenhetet —— chudtodengunheieteefeee

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Siac omen for aberymsgeent optimize across multiple competing objectives, allowing for their costs and measures ‘of uncertainy (See also Section 363) Where reserve planners do not have the fesources to use such sophisticated decision-support tools “dauble-payolf” resenve designs ean sill be achieved by careful problem formulation and an acceptance of both sets af objectives, established in conjunction with s broad range of sakebolders Comprehensive guidelines on designing MPAs are given ly Salm, Clarke nd Sirk (2000), Hal (2002),

and others, 2.3 USE RIGHTS

‘The FAO Code of Conduct notes that “States should prevent overfishing and excess fishing capacity” Such problems are usualy caused by the absence of property rights “The FAO has further efficient and responsible fisheries” (FAO, 1997), stated that “limited access widely considered tobe essential for Property rights govern who can do what with respect tothe resourse system and hhave been defined by Bromley (1991) as "the expacty to call upon the collective to stand behind one’s claim toa benefit stream”, Property rights are important in natural fesources management as they provide incentives for management, provide authority and control over the resource system, and can reinforce collective action (Meinzen: Dick and Koos, 1991) Thinking forwards $2 years, Rosenborg (1998) predicts that ‘open access will eventually hecome “sshing ofthe past”, anal cha property ight-base systems will be putin place for all fisheries, though there will be great variety ithe types of systems used Property right in fisheries manageonent are dealt with in detail jn Shorton (2000), Property rights have been divided into ewo groups by Schlager and Ostrom (1993) The fits group is usetights governing the usc of the sesource These mnay be further ive into access rights and withdrawal or haevesting rights Access ights authorize centey into the fishery oF into a specific fishing ground These include traditions systems for acess conteol sucl as TURFs, and limited acess contzols Withdrawal harvest) eights typically involve the right to a specific amount of fishing effort (ea to fish for a certain amount of time or with 3 certain amount of gese) or Uhe right 10 take a sposific each (quata or trip limit systems), Use rights in fisheries are discussed Jn deual by Charles 2002) The second! group is conteol rights, including management s that authorise the making of rules and imposition of restrictions, exshision ahs, which allow the holder ta determine wha may use the resource, and llenadon rights chat enable the holder to transter rights to others for example by inheritance ‘oF through sale or lease, Control rights provide the underlying bass for fisheries co ‘management, dealt with inthe following section These various rights can come from a number of sources inchiding international treaties, starutory legislation, religious practice, local custom, projet regulations and user group rules Several rights may coevst i relation to a single system (Meinven- Dick and Kaos, 19%: Benda-Beckman etal, 1996) There are als diferent possible combinations of rights thạt stakeholders mayo and these can vary between and ‘within stakeholder groups ‘When fisheries are managed by restricting who can have assess to the Fishery (access rights) andlor how much fishing etfore each individual i allowed or how much catch cach can take (withdrawal rights) then those individuals or groups holding such Cntitlements are std to have use rights, In cases where the stare has the capacity 10 enforce property rights and fisheries regulations, man: Fights isan option, These rights can be allocated by the sate to individuals o

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Fishery managment sytem

rights and misunderstanding over this has been the source of many disagreements ver tse rights management policies, As Charles (2002) nowes, decisions regarding allocation of use rights need to be made with care

2.3.1 Access tights The nes to egulate acess roa fishery i fundamental element of fisheries management (Charles, 2002) Unrestricted or "open acess” arrangements ithough often used with some techincal messores (se below), have le to significant oxereapsityin the world’s fisheries and much inefficient "racing behaviour” in fishing, Sestion 7.1.8 of the FAO Cade of Conduct thas recommends that "States should take nneasnres to prevent or eliminate excess fishing capacity and should ensure that levels of fubing effort are consmensirate with she sustainable use of fishery resources 4s 4 means of ensuring tbe effecivenes of conservation and management measares" While messures need £0 bye taken to limit elfor in a tnhery, particular care will be nese f the measures are intended to be equitable sd to reflect historical dependencies and rights (sec FAO, 1997; Greboval, 1999) ‘Access may be restricted (and acoess rights thereby applied) using ewo methods Te frst ofthese isthe use of terttorial use rights (TURES), where certain areas ace recognized as under the waditional or allocated control of certain individuals, tribes

sndlor groups, The second is by limiting entry to the fishery to certain individuals throngh restrict licensing Access regulations used asa sole management or casure have been criticized because, while they ate effective in controlling the number of fishers or vessels in the flee, incentives sil exist for the fishers wo race for the fish and to increase their individual caching power In such eases additional individual effort and cate responsibility

hts may also be ncaed, or incentives for collective

2.3.2 Withdrawal (harvest) rights Withdrawal or harvest rights include the right z0 apply a certin amount of fishing cffor or the sigh ro extract a certain output (i eatch) from te fishery Effort rights exist where measures ate taken 10 control the fishing effore expended eg theough restrictions placed on the number and/or types of gears) vse and/or on the amount ‘of time that ean be spent fishing Where effort rights are employed, managers shoul bbe awace of *eeshnology crsep” whereby the etlctiveness of 3 set of inputs (og 3 single fish rap haul} will increase overtime Oueput rights include catch quotas (ten ' proportion of the Taal Allocated Catch) that may be held by groups or individuals, slowing them to harvest that part wf the fish resource Indivieal quotas (1s) may be either non-transferable or tradable, as in the ease of Individual Transferable Quotas (17Qs} Crtiea issues with 1Qs,inchuding their duration, allocation andl transferability are discussed by FAO (1997), Shottom (2090) and Charles (2002), COuepor rights ae less prone to problems with technology eroep thaa effore rights and avoid the ace to fish However they can alse lead to other peoblems such as social ‘ncerns and conservation problems incaing incentives so under report catches oF to discard low-value sizes of fish to “high monitoring costs are also higher, Some argue thatthe full benefits of private ownership will only be realized when the actual quotas are also set by the ITQ holders 1 exzfully formulated, use rights should make conservation measures more compatible with the fishers’ own long

grade” the catches Data collection and

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Shock sasoent fr fiery management with diferent use rights approaches will ary A system of ITQs may be costly to appl, though the costs may be recoverable by fees applied to the rights holders Chiles (2002) suggests thar community-based rights may be more appropriate for small-scale! anisanal fisheries where mukipl fishery and non-fishery goals are pursued and that market-based rights may be beter in industrial fisheries that do not support coastal communities and where economic profitability isthe main goal All management regimes using harvest rights will require stock assessments to ‘estimate the effort or eatch to be allowed each year Accers rights in contrast may only state who (eg which community or fisher cooperative) is allowed to fishin a stated area In community based management systems, traditional rules almost always relate to fisher behaviour and technical measures (Section 25.5) rather than quantitative {quotas or effort controls, However, while the state can identify targets and limits and se ‘quotas it often lacks the capacity to enforce withdrawal rights and fisheries regulations fr to monitor resource use atthe local level, In such cases attention has been turning to the possibilty of the state devolving contol rights and co-managing the resources with resource users and other stakeholders, as deseribed in the following section,

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2.4 CONTROL RIGHTS AND FISHERIES CO-MANAGEMENT

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Fishery management stems

‘owners fish traders, money lenders, tourism establishments et) share the responsibility and authority for decision making in the management ofa fishery While this definition emphasizes the sharing of decision-making, it has been sore common for government to devolve management responsibilities, typically for ‘monitoring and enforcement, without devolving the management rights (Meinzen- Dick and Knox, 1991; Hara, 2004) While this may be a6 a result of uncertainty about how best to move towards co-management, itis also not uncommon to hear government agency staff talking ofthe need to create incentives for usergroups to take ‘on management responsibilty while stl displaying reluctance to share real power in making management decisions (and few if any government officials including scientists working in the research provision “industry” for fisheries, have explicit incentives co foster power sharing or devolution) The outcomes in cases ofthis type of “instrumental co-management” have not been found to be much better thas for centralized management, often because stakeholders sil lack the incetive to manage ina sustainable manner (Meinzen-Dick and Knox, 1991; Viswanathan eal, 2003; Hara and Raakjaer Nielsen, 203; Hara, 2004; Raakjzer Nielsen etal, 2004) ‘Where co-management har occurred with devolution of both rights and esponsibliies, it has been assumed that stakeholders associated with the fishery will assume the roles previously held by government agencies (Meinzen-Dick and Knos, 1991) To be successful, this requires collective action in order to coordinate and egulae individuals’ behaviour are considered to be interdependent, particularly in common property resources such 25 fisheries where holding rights in ‘common can reinforce collective action by the group and where collective action is requiced for resource management (Meinzen-Dick and Di Gregorio, 2004) Together they define incentives for adopting co-management stratepies that ate both productive ad sustainable The degree to which collective action is possible depends, in the First place, upon existing institutional arrangements providing an enabling enviconment This includes the state providing for the possiblity of such action through the devolution of control rights without requiring engchy or costly procedures In addition, secure property rights are an important clement and need to be of suicent duration to saable a return on investment and be backed by an effective enforcement institution, ‘often, though not exclusively the government, enabling users to take a longer-term view of resource use While successful collective action ie central to co-management arrangements, even when rights are established, much will depend on the attbutes of the participant (ee for example Dietz et a, 2002; Ostrom, 1990; Pomeroy, Katon and Harkes, 2001 and Baland and Plateau, 1998) Capacity building is therefore an important element in many co-management initiatives (Hara and Reakjaer Nielsen, 2003; Cornwall and Jewkes, 1995) ‘The FAO Technical Guidelines for Responsible Fisheries (1997) promote ‘management partnerships involving the different stakeholders in che fishery Such arrangements need to be carefully negotiated and deuailed in a management plan ‘The stakeholders involved and their roles and responsibilities will be very context dependent and may need to change over time As Sen and Nielsen (1996), Dietz et ‘a (2002), Pomeray (2003) and others have pointed out, there is no single opcimum arrangement and the bes strategy for managing the resource system will depend upon the characersties of both the resource and the users Indeed, i i recognized that co-management arrangements exist in variety of forms and with differing roles and ‘esponsbiliies for the stakeholders involved [a some cases the seal and nature of the resource system may be such that nerworks of small co-management units may offer ‘good opportunites Tanger, offshore fisheries, national governments and even international organizations for learning and adaptive management (see Section 2.1.3), For the

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8

Siac eseument for fey management In most co-management arrangements, given the devolution of control eights tan bbe expected that those dependent upon the fishers, or dei represenratves, will have, oF will develop the ability to establish rules and sanctions 2 well as

ake decisions about “organiringcollestive ation an the management ofthe resource system, nelng the methods used to guide the fishery (reference points, stock assessment models etc) As noted by Pinkerton (2902) “when communities or organizations of fishers are cluded 25 parters in the planning, desiga, and implementation ofthe regulations, when they pasticipate in protccting habitat and even more, when they are pat of the crafting of the very policies which underlie management devsions, they grant full legitimacy to the regulations, and are the strongest advocates, eonitors enforcers, and implementers ‘of management decisions Although there are clear benefits, experiences with co-management, including within a number of EMSP projects, hve shown that iis neither simple nor quick to “establish, Co-managen

nt wil be essier to apply in some places than others lists of ‘conditions that will encourage elfective co-management ate siven by Pomeroy and Williams (1994), Berkes etal (2001), Pinkerton (2292) and Olsson, Falke and Berkes (2004) Berkes etal (2001) and Hara and Raakjer Nilsen (2593) emphasize the need to Balance the needs of resource management and! community development, and to focus on capacity building of individuals and stakeholder groups, and the institutional arrangements that are ssed (for informed decision making, conflict management, learning processes, legal supports networking ets) Working with local stakeholders is nor necessarily easy anal equires special training an skills Amongst ather things, they may be sceptical about investing time an elfors,pariculey if they perceive only Timited personal benefits from their involvement in the process (Cornwall and Jewkes, 1995, Eyben and Ladbury, 1998) Co-management requites vompeomise, respect and

trust among stakeholders anda commitment 10 transparency, empowerment and commianiestion al of which may taketime to develop, especially against a ackground ‘f top-down regulation and control, Methods that enable ths ae therefore crucial CCo-management thus requires that government agencies and researchers adopt a sew way of thinking, develop new skis and find new ways of interacting wich other stakeholders (Garaway and Arthur, 2002; Hara and Raakjaer Nielsen, 2003) There is ‘often lgacy of some mistrast on both sides that needs ia be avercome Though this ean ‘ean having to accept slow proggess in the nial stages, building crusts fundamental in developing co-management (eg Jentole, 2093) Important roles include mediation and conflict resolution 35 well as prosiing technical snpport, eveit, marketing sistance and, critically, enabling legislation (Pomeroy and Berkes, 1997; Pinkerton, 2003), While those dependent on the fishery may have knowledge of local resources and needs, they foften đo aot have access to larger scale perspective and the technical and scientific Iknovsedge that can asist in realizing beneficial resource management decisions Co- ianagement partaerships must sherfore improve the knowledge base for management, snd communication beowsen stakeholders abous management options and the trade-offs snd risks associated with dhem (Hea and Raakjaer Nicken, 2933; Borisi-eyerabend fal, 2000) Government agencies and researchers may play an important cole inthis respect (see Garaweay and Arthur 2004, for guidelines In order to assnt practitioners, guidelines for co-management have been developed through FMSP projects both for opiesl coastal fisheries (Anderson, Mees and Cowan, 198), and for floodplain sver fisheries (see Hoggan et, (99% Hoggarh, 1999) Specific guidelines for using “adapeve co-management", ie adapsive management in 3 co-management seting where the emphasis is on developing and supporting laeaing processes, were developed by FMSP projects R7385 and R822 (Garaway and Arthur, 2002, Garaway and Arthur 2034) Inaaldition 10 co-managemeat guidelines and stock assessment rool, the FMSP has