AZTI develops a genetic method to facilitate an ecosystem approach to fisheries management – European directives such as the Marine Strategy Framework Directive or the EU’s Common Fisheries Policy require fisheries management to ensure the sustainability of stocks.
In recent years, this management has moved towards a more holistic ecosystem approach, which not only considers the abundance of the stock and the fishing pressure it is subject to, but also how the species interacts with other species in the ecosystem, i.e. who eats whom and who competes against whom. Therefore, a better understanding of trophic relationships in the marine environment and how they vary spatially and temporally is needed.
This knowledge has historically been obtained through visual inspection of the contents of fish stomachs, a time-consuming task requiring a high level of taxonomic expertise, which is particularly challenging (if not impossible) when stomach contents are degraded.
In response to this problem, a multidisciplinary team at the AZTI Technology Centre, composed of experts in genetics, marine ecology and ecosystem modelling, developed and validated an innovative method to facilitate and accelerate the collection of trophic data for five highly commercial species in the Bay of Biscay: anchovy, sardine, hake, horse mackerel and mackerel.
The method, based on the analysis of DNA in fish stomachs, is designed to reduce the time needed to process the stomachs by improving the efficiency of genetic analysis. It also allows the simultaneous analysis of hundreds of samples to obtain a prey inventory for each one.
“Ours represents an accurate and reliable way to collect information on who eats whom and with what preference in the ocean, key data to increase our knowledge of the trophic structure of marine ecosystems,”
says Oriol Canals, marine genetics expert at AZTI.
“A greater understanding of the trophic relationships between marine organisms will facilitate the application of ecosystem approaches to fisheries management, ultimately ensuring sustainable exploitation of marine ecosystems and resources, which is of great value to the economy and the fisheries sector,”
adds the AZTI researcher.
The AZTI team demonstrated that genetic analysis outperforms visual inspection by identifying a wider range of prey, including fast-digesting prey such as jellyfish, which are usually overlooked by visual analysis, and are highly accurate in identifying spatial and temporal variations in fish diets.
“Furthermore, this genetic method is not only applicable to the five species studied, but can easily be adapted to other species,”
says Canals.
The research, led by the Technological Centre, was funded by the European Framework Programme for Data Collection (EUMAP) and the Basque Government’s Department of Agriculture and Fisheries through the GENGES project.
AZTI develops a genetic method to facilitate an ecosystem approach to fisheries management
