Cetacean Strandings and Sea Turtle Routes in the Bay of Biscay

The Basque Stranding Network has been up and running for 23 years; first, thanks to the involvement of the NGO AMBAR and, since 2022, under Plentzia Marine Station (PiE-UPV/EHU). Samples from cetaceans, pinnipeds, sharks and sea turtles are usually collected to be stored and analysed at Plentzia Marine Station’s Biobank. The stranding network is gradually becoming more professionalised. It ensures coordinated, effective and rapid support, along with the maximum wellbeing of the stranded species that are alive and avoiding crossover effects on human health.

The session will address the following goals:

• The importance of scientific research in protecting marine ecosystems.
• Applying biotechnology in the study and conservation of marine species.
• Biobanks and their role in preserving biodiversity.
• Factor that can affecting the stranding of marine mammals and sea turtles.
• Analysing sea turtle routes using satellite transmitters.

Analysing the data of all the stranded species between 1993 and 2023, which refers to the stranding places, shows that the beaches of San Sebastián are a recurrent point, where 81 strandings were recorded. The following municipalities should also be highlighted: Zumaia (46), Zarauz (43), Getxo (36), Sopelana (36), Bermeo (31) and Getaria (31).

On the other hand, species that are alive have been helped. Therefore, 5 sea turtles have been cured and released, in conjunction with San Sebastián Aquarium. The 2 loggerhead sea turtles that recovered at the Aquarium were released on 20/8/2004. The loggerhead sea turtle at the Gorliz Fauna Recovery Centre (Bizkaia) was admitted on 28/08/2024. In 2025, a further 3 sea turtles have been released after long stays at the Aquarium. Satellite transmitters were fitted to follow their journey. Their journeys will be shown during the session.