Climate versus human impacts on the marine fauna of the Mediterranean Sea during the pre-industrial period

Leal, D.; Agiadi, K.; Bas, M.

doi:10.1101/2025.02.05.636195

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bioRxiv · 10.1101/2025.02.05.636195

Climate versus human impacts on the marine fauna of the Mediterranean Sea during the pre-industrial period

Leal, D.·Agiadi, K.·Bas, M.

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Abstract

Historical baselines are essential for evaluating the cumulative impacts on modern marine ecosystems, particularly in regions such as the Mediterranean, where human activities have been intensive for millennia and climate change is accelerating. However, quantitative evidence of historical impacts remains fragmented. In this study, we investigate changes in the presence, abundance and body size of the Atlantic bluefin tuna, gilthead sea bream, banded-dye murex and turbinate monodont across the Mediterranean Sea from 130,000 years Before Present until the Industrial Revolution (1850 AD), using geological, archaeological, and historical records. Our results reveal significant temporal shifts in the abundance and body size of the banded-dye murex, Atlantic bluefin tuna and gilthead sea bream. Environmental factors, particularly seawater temperature, were the primary drivers of abundance and size in Atlantic bluefin tuna in the past. Human activities, especially exploitation, influenced the abundance of banded-dye murex and Atlantic bluefin tuna, as well as the body size of gilthead sea bream. These findings underscore the importance of integrating long-term ecological data to better understand the interplay between climate, human pressures and ecosystem dynamics.

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Leal, D., Agiadi, K., Bas, M.. 2025-02-07. Climate versus human impacts on the marine fauna of the Mediterranean Sea during the pre-industrial period. https://doi.org/10.1101/2025.02.05.636195

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