What is left and what was achieved? A time perspective of a pioneering project 20 years after the European Fish Ageing Network

Abstract

The European Fish Ageing Network (EFAN) funded by the European Union, is reviewed, and assessed after a 20-year hiatus. The large number of scientists and technicians involved in this independent and informal network, and the time invested (four years), provided a significant advance in fish age estimation and methodologies. The results presented are based on two survey questionnaires sent to EFAN members, specifically to those who had been most actively involved in the programme. Overall, EFAN can be considered as successful as it fulfilled the aim of the FAIR (Fostering Awareness Inclusion and Recognition) program in improving collaboration both at a national and European levels in the field of sclerochronology. Adding to the success was that many survey participants reported a positive impact on both their creativity and scientific careers, particularly participants from university environments and the female members, and around 50% of the participants continued in their age-related research careers. These factors, as well as the positive scientific impact EFAN has had in various European countries (n = 16), point to a very successful programme. The aim of improving what is an objective approach required to interpret growth increments in calcified structures (otoliths) in fishes, is reflected in the various tools developed by EFAN, all of which are found in the many reports produced by the Network. Examples are seen in the quality control approach by the International Council for the Exploration of the Sea (ICES), where tools developed by EFAN have been key to their fisheries management approach. Our general impression is that a project with a lifetime of around four years in principle provides a suitable time period to develop age estimation tools, quality control routines, and working procedures to improve the use of fish age data for fish stock assessments. We argue however, that developing a functioning network requires more time than a conventional project. Therefore, to fully meet the aims of projects such as EFAN, a period of between 10 and 15 years is a more appropriate time frame for these types of programmes to run. A longer time scale can help ensure recommendations are regularly followed, can provide more confidence in on-going routine age estimation data, and so achieve a significant improvement in the application of ageing methods. In turn a more accurate and robust scientific outcome would be available for European fish stock assessments.