Table of Contents

A Guide to Fisheries Stock Assessment

Chapter

Page
1. Stock Assessments: An Introduction
5
2. What Types of Data are Available?
7
Fishery-Dependent Data
7
   Landing Records
7
   Portside Sampling
7
   Onboard Observers
8
   Log Books and Vessel Trip Reports
8
   Telephone Surveys
8
Fishery-Independent Data
9
3. Biological Reference Points
11
Targets versus Thresholds
12
Determining Thresholds
13
Uncertainty
17
4. Population Dynamics Models: The Underpinnings of Stock Assessment Models
21
The Basic Population Dynamics Model
21
Adding Complexity: Mortality
22
Adding Complexity: Age Structure
23
Adding Complexity: Stock-Recruitment Functions
26
Adding Complexity: Weight and Biomass
28
5. Applying Stock Assessment Models to Data
29
Indices of Abundance
29
   Catch-per-Unit Effort
30
   Estimates of Actual Stock Size
31
Index-Only Models
31
Fitting Models to Data
32
   Frequentist versus Bayesian Approaches
32
   Biomass Dynamics Models—Theory
34
   Biomass Dynamics Models—Targets and thresholds
34
   Age-Structured Models—Theory
35
   Age-Structured Models—Targets and thresholds
37
   Estimating Uncertainty
37
6. Making Recommendations
39
Glossary
41