Marine resources have been overexploited for centuries, reducing fish populations and altering their behaviour and life cycle characteristics. However, the evolutionary impact of overfishing remains poorly understood, despite being crucial for predicting future population trends and ensuring sustainable fisheries management. Historical data help establish benchmarks for biodiversity, linking biology to history, economics, and culture. However, fishing records prior to 1950 are scarce, while archaeological remains of fish, despite their fragmentary nature, provide valuable information about past economies, diets, and environmental conditions. Ancient DNA (aDNA) techniques offer unique demographic and adaptive data that modern fishing records cannot provide, and studies demonstrate good preservation of ancient fish DNA.
This project focuses on hake (Merluccius merluccius), a species of high commercial value found in the North-East Atlantic, the Mediterranean and the Black Sea. It inhabits diverse environments, demonstrating a remarkable ability to adapt. Hake plays a fundamental trophic role in marine ecosystems, but decades of overfishing have raised concerns about its sustainability, with annual catches exceeding 100,000 tonnes. In the European archaeological record, traces of hake are rare, possibly due to taphonomic processes, as its bones are more fragile than those of other Gadidae, such as cod. Written records also obscure its historical importance, as hake was often referred to under generic fish names, leading to a likely underestimation of its relevance in pre-industrial exploitation.
Commercial records suggest that hake was transported inland as early as the early Middle Ages, but the true extent of its historical exploitation remains unknown. Hake populations are divided into three stocks: a North Atlantic stock, an Iberian Atlantic stock and a Mediterranean stock. However, genetic studies reveal significant genetic flow between Atlantic stocks, highlighting a discrepancy between management units and population structure. Fisheries assessments are carried out annually, but current management strategies may not be fully aligned with the genetic diversity of the species.
This project aims to analyse historical changes in hake exploitation in the Iberian Peninsula and assess the continuity or replacement of populations following industrial overfishing. These results will contribute to evidence-based conservation strategies, assisting fisheries experts and organisations such as the International Council for the Exploration of the Sea (ICES) in implementing more effective management protocols.