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Handbook of Fish Age Estimation Protocols and Validation Methods

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Handbook of Fish Age Estimation Protocols and Validation Methods #346 APRIL 2019 Handbook of fish age estimation protocols and validation methods ICES COOPERATIVE RESEARCH REPORT RAPPORT DES RECHERCHES COLLECTIVES ICES INTERNATIONAL COUNCIL FOR THE EXPLORATION OF THE SEA CIEM CONSEIL INTERNATIONAL POUR L’EXPLORATION DE LA MER ICES COOPERATIVE RESEARCH REPORT RAPPORT DES RECHERCHES COLLECTIVES NO. 346 APRIL 2019 Handbook of fish age estimation protocols and validation methods Editors Francesca Vitale • Lotte Worsøe Clausen • Gráinne Ní Chonchúir International Council for the Exploration of the Sea Conseil International pour l’Exploration de la Mer H. C. Andersens Boulevard 44–46 DK-1553 Copenhagen V Denmark Telephone (+45) 33 38 67 00 Telefax (+45) 33 93 42 15 www.ices.dk [email protected] Recommended format for purposes of citation: Vitale, F., Worsøe Clausen, L., and Ní Chonchúir, G. (Eds.) 2019. Handbook of fish age estimation protocols and validation methods. ICES Cooperative Research Report No. 346. 180 pp. http://doi.org/10.17895/ices.pub.5221 Series Editor: Emory D. Anderson The material in this report may be reused for non-commercial purposes using the rec- ommended citation. ICES may only grant usage rights of information, data, images, graphs, etc. of which it has ownership. For other third-party material cited in this re- port, you must contact the original copyright holder for permission. For citation of da- tasets or use of data to be included in other databases, please refer to the latest ICES data policy on the ICES website. All extracts must be acknowledged. For other repro- duction requests please contact the General Secretary. This document is the product of an Expert Group under the auspices of the International Council for the Exploration of the Sea and does not necessarily represent the view of the Council. Cover image: © OCEANA/Carlos Suárez DOI: http://doi.org/10.17895/ices.pub.5221 ISBN 978-87-7482-223-3 ISSN 2707-7144 © 2019 International Council for the Exploration of the Sea Contents Foreword ................................................................................................................................... i Acknowledgements .............................................................................................................. ii 1 Introduction .................................................................................................................... 1 1.1 Why do we age read fish? .................................................................................. 1 1.2 The history of quality assurance and quality control (QA/QC) .................... 1 1.2.1 Tools available for quality assurance and quality control .................. 3 1.2.2 The concepts of accuracy and precision ................................................ 4 1.2.3 Validation .................................................................................................. 5 1.2.4 Direct validation methods ....................................................................... 7 1.2.5 Indirect validation methods .................................................................... 7 1.3 Standardization of procedures ......................................................................... 10 1.3.1 Why standardization is needed ............................................................ 10 1.3.2 Monitoring performance ....................................................................... 10 1.3.3 The benefits of having agreed (validated) manuals .......................... 11 1.4 Accreditation ...................................................................................................... 12 1.5 Contributors ....................................................................................................... 14 2 Gadoids .......................................................................................................................... 15 2.1 Introduction ........................................................................................................ 15 2.2 Age estimation methodologies in gadoids ..................................................... 15 2.3 General age estimation methods and problems ............................................ 17 2.3.1 Saithe (Polliachius virens) ........................................................................ 17 2.3.2 Whiting (Merlangius merlangus) ............................................................ 17 2.3.3 European hake (Merluccius merluccius) ................................................ 18 2.3.4 Cod (Gadus morhua) ................................................................................ 19 2.3.5 Blue whiting (Micromesistius poutassou)............................................... 20 2.4 Age validation case studies in gadoids........................................................... 20 2.5 Application of indirect validation methods ................................................... 22 2.5.1 Length-based analyses ........................................................................... 22 2.5.2 Marginal increment analysis ................................................................. 23 2.5.3 Edge-zone analysis ................................................................................. 24 2.6 Application of direct validation methods ...................................................... 24 2.6.1 Tag–recapture ......................................................................................... 24 2.6.2 Rearing in captivity ................................................................................ 26 2.6.3 Daily increment analysis ....................................................................... 27 2.7 Future perspectives in gadoids: available tools ............................................. 28 2.7.1 Back-calculation of size at previous age and hatch date ................... 28 2.7.2 Simulation tools for otolith macrostructure modelling ..................... 29 2.7.3 Raman microspectrometry .................................................................... 29 2.7.4 Microchemistry as a supportive tool for age validation ................... 30 2.8 Ongoing and future work ................................................................................. 32 2.8.1 Validation of life history events – juvenile check............................... 32 2.8.2 Validation of life history events – spawning check ........................... 33 3 Flatfish ........................................................................................................................... 36 3.1 Introduction ........................................................................................................ 36 3.2 Age estimation methodologies in flatfish ....................................................... 45 3.2.1 Whole otolith method ............................................................................ 45 3.2.2 Break-and-burn method ........................................................................ 47 3.2.3 Sectioned otolith method ...................................................................... 48 3.2.4 Sectioned and stained ............................................................................ 49 3.3 Age estimation problems and features of specific flatfish stocks ............... 49 3.3.1 Plaice (Pleuronectes platessa) ................................................................... 49 3.3.2 Sole (Solea solea) ....................................................................................... 50 3.3.3 Turbot (Scophthalmus maximus) and brill (Scophthalmus rhombus) ................................................................................................... 51 3.3.4 Lemon sole (Microstomus kitt) ............................................................... 51 3.3.5 Megrim (Lepidorhombus whiffiagonis) and four-spot megrim (Lepidorhombus boscii) ............................................................................. 52 3.3.6 Flounder (Platichthys flesus) ................................................................... 53 3.3.7 Witch flounder (Glyptocephalus cynoglossus) ....................................... 54 3.3.8 Dab (Limanda limanda) ............................................................................ 55 3.3.9 Greenland halibut (Reinhardtius hippoglossoide) .................................. 56 3.4 Age validation case studies .............................................................................. 56 3.4.1 Lemon sole (marginal increment analysis) ......................................... 58 3.4.2 Plaice and sole (mark–recapture) ......................................................... 58 4 Small- and medium-sized pelagic species .............................................................. 59 4.1 Introduction ........................................................................................................ 59 4.2 Summary of age estimation methodologies ................................................... 59 4.3 Summary of general age estimation methods and problems ...................... 66 4.3.1 Anchovy (Engraulis encrasicolus) .......................................................... 66 4.3.2 Sardine (Sardina pilchardus) ................................................................... 71 4.3.3 Herring (Clupea harengus) ...................................................................... 73 4.3.4 Sprat (Sprattus sprattus) .......................................................................... 74 4.3.5 Mackerel (Scomber scombrus) ................................................................
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