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Workshop on Micro Increment Daily Growth in European Anchovy and Sar- Dine (WKMIAS)

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Workshop on Micro Increment Daily Growth in European Anchovy and Sar- Dine (WKMIAS) ICES WKMIAS REPORT 2013 ICES ACOM COMMITTEE ICES CM 2013/ACOM:51 REF. PGMED AND PGCCDBS Workshop on micro increment daily growth in European Anchovy and Sar- dine (WKMIAS) 21-25 October 2013 Mazara del Vallo, Sicily 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: ICES. 2014. Workshop on micro increment daily growth in European Anchovy and Sardine (WKMIAS), 21-25 October 2013, Mazara del Vallo, Sicily. ICES CM 2013/ACOM:51. 153 pp. For permission to reproduce material from this publication, please apply to the Gen- eral Secretary. The document is a report of an Expert Group under the auspices of the International Council for the Exploration of the Sea and does not necessarily represent the views of the Council. © 2014 International Council for the Exploration of the Sea ICES WKMIAS REPORT 2013 | i Contents Executive summary ................................................................................................................ 1 1 Introduction .................................................................................................................... 3 2 Ecosystem and biology considerations for anchovy and sardine populations ..................................................................................................................... 5 2.1 Anchovy ................................................................................................................. 5 2.2 Sardine .................................................................................................................... 6 3 Review literature and consider recent research to define daily increment patterns in anchovy and sardine .............................................................. 8 3.1 Introduction ........................................................................................................... 8 4 Standardization of Material and methods for preparation of otolith thin sections in anchovy and sardine ............................................................................... 16 4.1 Species and areas ................................................................................................ 16 4.2 Review Material and techniques ...................................................................... 16 4.3 Review Method image process ......................................................................... 16 4.4 Standardization of protocols ............................................................................. 21 4.5 Alternative techniques for standardize the age estimation. ......................... 21 Age estimation by discriminant analysis in ANCHOVY larvae ....................................................................................................... 22 Age estimation by discriminant analysis in SARDINE Juveniles .................................................................................................. 25 5 Definition and standardization of reading criteria among areas ........................ 29 5.1 Review Reading criteria ..................................................................................... 29 5.2 Review Validation .............................................................................................. 29 5.3 Review Quality control ...................................................................................... 29 5.4 Results from the otolith reading exercise in anchovy and sardine for the standardization of the adoption of ageing criteria .................................. 30 5.5 Definition and standardization of age assignment protocol......................... 30 6 Validation of the first annulus in young of the year anchovy and sardine ............................................................................................................................ 32 6.1 Anchovy Corroboration ..................................................................................... 32 Material and methods ........................................................................... 32 Results ..................................................................................................... 33 Conclusion and Discussion .................................................................. 36 Anchovy Validation ............................................................................... 36 6.2 Sardine Corroboration ....................................................................................... 37 ii | ICES WKMIAS REPORT 2013 7 Growth pattern of juvenile anchovy and sardine in different areas/environments ..................................................................................................... 39 7.1 Collection of information on growth patterns ................................................ 39 7.2 General considerations for each life stage and species .................................. 49 7.3 Concluding remarks ........................................................................................... 51 8 Precision and accuracy of age estimates by micro-increment counts ................. 52 8.1 Material and Methods ........................................................................................ 52 Participants and qualification of readers ............................................ 52 Otolith images of Anchovy and Sardine collection ........................... 53 Guideline on daily age reading ............................................................ 54 Analysis of the daily age readings ....................................................... 54 8.2 Results of the 2013 Otolith Image Exchange ................................................... 55 Anchovy results ..................................................................................... 55 Sardine results ........................................................................................ 62 Aquaculture juveniles of Sardine from Atlantic Iberian set ............. 69 Evaluation of the 2013 Anchovy and Sardine Otolith Image Exchange ................................................................................................. 72 8.3 Results of comparative daily age readings at the Workshop ....................... 73 Anchovy Results (see also annex 6) ..................................................... 73 Sardine results (see also Annex 7) ....................................................... 74 Evaluation of the Anchovy and Sardine Otolith Workshop ............ 75 9 Reference collection of otolith images ..................................................................... 77 10 Contributions to the Workshop (abstracts) ............................................................. 78 11 Acknowledgements ..................................................................................................... 94 Annex 1: List of participants ............................................................................................. 95 Annex 2: WKMIAS final Agenda .................................................................................... 96 Annex 3: Recommendations ............................................................................................. 99 Annex 4: WKMIAS terms of reference for the next meeting .................................... 100 Annex 5: Reference collection of otolith images ......................................................... 101 Annex 6: Results of anchovy otolith reading exercise during WKMIAS ............... 128 Annex 7: Results of sardine otolith reading exercise during WKMIAS ................. 139 Annex 8: Questionnaire sent to the participants before WKMIAS ......................... 153 ICES WKMIAS REPORT 2013 | 1 Executive summary The Workshop on Micro increment daily growth in European Anchovy and Sardine (WKMIAS) met for the first time from 21-25th October 2013 in Mazara del Vallo, Sicily (CNR-IAMC). The meeting was chaired by Gualtiero Basilone (CNR-IAMC, Italy), Be- goña Villamor (IEO, Spain) and Mario La Mesa (CNR-ISMAR, Italy). Six nations were represented by 22 participants. WKMIAS was proposed by the Planning Group on Commercial Catches, Discards and Biological Sampling (PGCCDBS) 2012. Many activities of this group are closely linked to the activities of the Data Collection framework (DCF). Although under the ICES have been made multiple age reading workshops at annual scale, this was the first time that a workshop was dedicated exclusively to age reading at daily scale. The objectives of the workshop were to define and standardize methods, reading criteria and proto- cols of anchovy and sardine daily growth in different developmental stages (larvae and juveniles), and validate the first annual ring of these species to improve annual age estimates. The report summarizes the work in relation to each of the ToRs. Given the terms of reference and objectives, the daily growth of these species is dealt with the following geographical areas/stocks/ecosystems: Bay of Biscay, Atlantic Ibe- rian Peninsula (sardine only), Western Mediterranean, Strait of Sicily, Adriatic Sea and North Aegean Sea. Before the workshop, a questionnaire was performed in which each laboratory should provide information on their method of preparation and interpretation of the anchovy and sardine otolith microstructure. The result of them was reviewed and summarized, reaching a common protocol during
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