EFAN Report 5-2000

Guidelines for the Quality Assurance of Fish Age Determinations

By

W. J. Mc Curdy, Appelberg M., Ayers R., Belcari P., Bolle L., Cendrero O.,
Easey M.W., Fossum P., Hammer C., Hansen F. I., Raitaniemi J.

European Fish Ageing Network (EFAN)

For further information, please contact:

EFAN, Institute of Marine Research, Flødevigen Marine Research Station, N-4817 His, Norway.

Phone: (47) 37 05 90 00; Fax: (47) 37 05 90 01; Email: bente.lundin@imr.no

Office address: Flødevigvn. 49, Hisøy (Arendal), Norway.

Coordinator: Erlend Moksness, Phone (direct): (47) 37 05 90 41; E-mail: moksness@imr.no

,o:p>

Guidelines for the Quality Assurance of

Fish Age Determinations

Version 1.0 October 2000

W. J. Mc Curdy, Appelberg M., Ayers R., Belcari P., Bolle L., Cendrero O.,
Easey M.W., Fossum P., Hammer C., Hansen F. I., Raitaniemi J.

Willie J. Mc Curdy, Dept.of Agriculture and Rural Development for Northern Ireland,

18a Newforge Lane, Belfast PT9 5PX, N. Ireland, UK

e-mail address: willie.mccurdy@dardni.gov.uk

Direct phone: +44 2890 255513

Magnus Appelberg, Institute of Freshwater Research, National Board of Fisheries,

S-178 93 Drottningholm, Sweden

e-mail address: magnus.appelberg@fiskeriverket.se

Direct phone: +46 86200435

Richard Ayers, CEFAS, Fisheries Laboratory,

Pakefield Road, Lowestoft, Suffolk NR33 0HT, UK

e-mail address: r.a.ayers@cefas.co.uk

Phone: +44 1502 562244

Paola Belcari, Dipartimento de Scienze dell'Uomo & dell'Ambiente (D.S.U.A.),

Via Volta 6, 56126 Pisa, Italy

e-mail address: belcari@discat.unip.it

Phone: +39 50 500018

Loes Bolle, Netherlands Institute for Fisheries Research (RIVO),

P.O. Box 68, 1970 AB Ijmuiden, the Netherlands

e-mail address: loes@rivo.wag-ur.nl

Phone: +31 255 564646

Orestes Cendrero, Instituto Espanol de Oceanografia,

Apdo. 240, 39080 Sandander, Spain

e-mail address: orestes.cendrero@st.ieo.es

Direct phone: +34 942 291068

Mick W. Easey, CEFAS, Fisheries Laboratory,

Pakefield Road, Lowestoft, Suffolk NR33 0HT, UK

e-mail address: m.w.easey@cefas.co.uk

Phone: +44 1502562244

Petter Fossum, Institute of Marine Research,

P.O. Box 1870 Nordnes, N-5817 Bergen, Norway

e-mail address: petter.fossum@imr.no

Direct phone: +47 55238633/8503

Cornelius Hammer, Fed. Research Center for Fisheries, Institute for Sea Fisheries,

Palmaille 9, D-22767 Hamburg, Germany

e-mail address: hammer.ish@bfa-fisch.de

Direct phone: +49 4038905-232

Frank Ivan Hansen, Danish Institute for Fisheries Research,

Charlottenlund Castle, DK-2920 Charlottenlund, Denmark

e-mail address: fih@dru.min.dk

Direct phone: +45 33963363

Jari Raitaniemi, Finnish Game and Fisheries Research Institute,

P.O. Box 6, FIN-00721 Helsinki, Finland

e-mail address: jari.raitaniemi@rktl-fi

Phone: +358 205 751340

Further copies or updated versions of this paper can be downloaded from the EFAN website:http:/www.efan.no (Activate the Guidelines button).

THE ULTIMATE GOAL OF EFAN IS TO HARMONISE AGE READING IN EUROPE AND TO WORK FOR IMPROVED COHESION

Abstract

There are three fundamental principles that underpin any successful strategy for the process of continuous improvement within fish age determination methodology.

Firstly it is critically important to foster an environment where all persons involved in the age determination process are able to accept that they genuinely do have shared ownership of the complete process from sample collection, to application of the age estimations.

Secondly in this context, everything possible including exchanges and workshops, must be done to ensure that innovation and creativity are both highly valued and that together with the need for Quality Assurance, are perceived to be a necessary and integral part of the process of evolving methodology for fish age determinations.

Thirdly Quality Assurance cannot be implemented successfully unless sufficient funds and personnel resources are made available for this purpose.

The Guidelines given in this paper outline the principal areas of concern that should be addressed within any Quality Manual for the effective Quality Assurance for fish age determinations.

Introduction

Quality has many meanings and implications, from quality of services to the quality of organisations themselves. However, in whatever form, quality remains a means to an end and not the end itself (Silva Menedes 1996).

From the beginning of EFAN the question of Quality Assurance (QA) for fish age determinations has been a constantly reoccurring issue. The pressure on providing better and more reliable basis for assessments has been growing and is documented in the repeated criticism that assessments of marine stocks are insufficiently reliable. This pressure towards improvement is being partly passed on to the national labs.

The principal goal of this process, is the development of methods applicable to the range and scope of the fish age determination activities carried out within any institute, that are able to clearly evidence the mechanisms which transparently sustain the precision and accuracy of the results.

The overall objective of the QA is the improvement of the reliability of the age reading process. The challenges include;

· Traditionally age reading has been a subjective process.

· In many cases readers are left to deal with the quality issue on their own, in the trust of their superiors that high quality of the age readings is provided by the long individual experience.

Quality management strategies have been understood and implemented in the manufacturing industries for many years. Some public authorities have already started to use quality tools in their policy development and deployment, as a response to the ever present demand for improvement in constantly changing environment.

Benchmarking for example, i.e. the identification and comparison of best practices, is just as applicable to age readings as it is to governmental policies, or the management processes and commercial decisions of private enterprise.

The importance of age reading has been growing with the increasing demand for quality in the assessment work used as the basis for management advice;

· Stock assessment in the classical sense mainly used by international bodies

· Ecological quality objectives as determined by e.g. the EU's Water Framework Directive and OSPAR

The Quality Assurance Process

Quality Assurance is a cyclical process and consists of:

1. Written Procedures designed to implement Best Practice.

2. The application of these Procedures to the Age Reading Process.

3. The inspection of the process and its outputs to ensure that an acceptable level of Quality is being achieved.

4. The revision of the process to improve the Procedures where the required quality standard is not attained.

In essence Quality Assurance is a continuous process of planning, doing, controlling and revision. The input of the EFAN Cells to this process is shown in fig. 1.

The needs of the customer are outside the cyclical Quality Assurance process, but they need to be clearly defined for the Quality Assurance process to be successful. The Quality Manual must define;

· The nature of the customer base, who are the customers?

· What level of Quality is required

· The processes covered by the Quality Manual

· How the Quality Assurance for these processes will be delivered

· The role of the Quality manager.

The Quality Manual should also define the Customers’ commitment to maintain an effective Quality environment that will support the Quality Assurance process. This will include a commitment to Age Reader motivation through involvement in use of fish age data and inter institute contacts via regular meetings and access to the websites of other institutes. Good quality age readings depends on the readers’ enthusiasm and it is essential that age readers have confidence in own readings.

Validation

To refine and develop QA, there is a need for an open communication between the QA and the scientific developments within the field. For assessing the accuracy in fish ageing, this becomes especially important concerning the possibility to provide fish samples where age has been defined by another, independent, method than the one used in the original analysis. Where there is a lack of known age material, sources such as reference collection materials with ages defined from daily ring counts, may be of considerable value in validating annuli readings early in the life history of some species.

Link between Age Reading and the Research

Scientific development is also the guarantee for the evolution of new methods and procedures, that will increase accuracy and precision of fish age determinations. QA is not something that can be designed in isolation. Scientific findings and QA share common principles, e.g. the repeatability of results and peer reviewing of proposals and results, while the Science itself is an integral part of the QA process.

Financial support for Quality Assurance

The demand for Quality Assurance increases the cost of the age readings and these additional costs will have to be funded by individual Laboratories. However Quality Assurance should in the long run be cost effective, although in the short term it will require additional investment from institutes. The current situation where financial support is primarily not provided for exchange of ideas and experiences between individual age readers, does serve neither the interests of Quality Assurance nor the needs of the end-customers.

DEFINITION OF AGE READING PROCEDURES

· All procedures must be written down.

· Age readings must be preceded by an effective sampling programme

The standards that are to be achieved for the complete process of fish ageing and include fish sampling and the handling of the fish age data are outlined below:

1. Fish Sampling

1.1 Measurements of fish - the method of measurement must be clearly

defined.

1.2 The integrity of the links between the data and the age reading materials

must be maintained at all times.

1.3 All the information required in addition to the measurements themselves,

must be specified, e.g. species, area, date, fishing gear, sex, maturity.

2. Selection of Age Reading Materials

2.1 Which hard structures are to be used.

2.2 The preferred sampling site(s) for scale removal, this may vary with the

species and the requirement

2.3 Standards to be shared between institutes working on common stocks

3. Conservation of Age Reading Materials:

3.1 Cleaning method e.g. removing muscular tissue and fats from whole bones and

drying.

3.2 Transport and storage must prevent damage and deterioration

3.3 Handling of Age Reading Materials

3.4 Control of moisture content

4. Species specific preparation techniques

4.1 Criteria for acceptance/rejection of age reading materials

4.2 Preparation techniques

4.2.1 Burning

4.2.2 Staining

4.2.3 Grinding

4.2.4 sawing

5. Age Reading equipment

5.1 Reading equipment set up (e.g. binocular microscope)

5.1.1 Magnification level,

5.1.2 Light intensity

5.1.3 Type of illumination

5.1.4 Equipment quality, define the equipment to be used in

each process

5.1.5 Confidence in equipment

5.1.6 Training use of equipment

5.1.7 Image analysis/digitisation

6. Age Reading Procedure (Manual)

6.1 Time planning for readings and re-readings

6.2 Use of Glossary (1^st Otolith Research Symposium, Hilton Head, 1993)

6.3 Where to start reading

6.4 Definition of rings

6.4.1 Criteria for genuine/ false rings

6.4.2 Number and location of reading axes

6.4.3 Potential age reading problems

6.4.3.1 Double rings

6.4.3.2 Juvenile growth

6.4.3.3 Incomplete growth rings in older fish

6.4.3.4 Edge patterns

6.5 Providing additional information when reading calcified structures

6.5.1 Advantages

6.5.2 Disadvantages

6.6 Ideally ring reading followed by conference reading

7. Recording Age Readings

7.1 Age (and fish) data

7.1.1 Sample ID

7.1.2 Reader identity

7.1.3 Data storage

7.1.4 Ability to trace data edits

7.1.5 Handling and processing the data

7.1.6 Backup of databases

7.1.7 Responsibility for the data at different stages

7.2 Training new readers:

7.2.1 Teaching new readers

7.2.1.1 Conference reading with skilled reader who has good

presentation skills.

7.2.1.2 Discussion of sample problems with mentor

7.2.2 Benefits of conference reading

7.2.3 All calcified structures must be re-read until sample readings reach target agreement level.

7.2.4 Requirement for basic information on calcified structure or other structure

7.2.5 Requirement for information on the biology of the species

7.2.6 Training log

7.2.6.1 Training course units e.g. preparing calcified structures, calcified structure reading, data handling

8. Inspection and Control of the process

8.1 Effective validation is mandatory for Quality Assurance,

8.2 Apply EFAN Guidelines for Validation Studies

8.3 Apply EFAN Tools and Guidelines for Age Reading Comparisons

8.3.1 Reader accuracy checks

8.3.2 Reader precision checks

8.4 Statistics on readings returned to readers

9. Revision of the Procedures to improve the process

9.1 Revision of procedures/age reading is initiated by errors found in the control process.

9.2 Revision of Procedures can be initiated by scientific and technical developments.

9.3 Revision of procedures should always rely on;

9.3.1 Scientific development within the field

9.3.2 Technological development within the field

9.4 Revision should always be performed as specified in the manual

Conclusions

· The input of end-customers in the quality chain is essential and acceptable QA thresholds must be defined.

· It should be of significant importance that performance controls are carried out on a regular basis, for all age readings.

· The uniform application of standard methods and excessive harmonisation. A variety of methods may coexist providing that each has effective quality assurance.

· Exchanges of personal experience will encourage the evolution methods that focus more directly on the "Best Practice" necessary to achieve the common goals of accuracy and precision.

· The potential for IT advances to contribute to the Quality of Fish ageing must not be overlooked.

References.

Silva Mendes, A. 1996. A European Quality Promotion Policy For Improving European Competitiveness. SEC (96) 2000, 30 October 1996, Quality Series nr. 1. Directorate General III Industry, Unit III/A/3, Industrial Competitiveness.

Figure 1

Objectives & demands by customer