Unraveling The Secrets Of Mediterranean Sharks: Critical Research Receives National Geographic Funding

Dr. Scheinin and Dr. Livne prepare and deploy a bottom longline at 60 m depth in Boncuk Bay, Turkey, ... [+]AKDENIZ KORUMA/MEDITERRANEAN CONSERVATION SOCIETY

By Melissa Cristina Márquez Published:

University of Haifa researchers have received a substantial $100,000 grant from National Geographic Wayfinder to conduct a groundbreaking study to track the movement of sharks in the eastern Mediterranean Sea (EMS). Home to a rich and diverse marinescape, its biodiversity encompasses a wide range of marine organisms, including fish, invertebrates, corals, marine mammals, and seabirds. Despite the region’s climate change challenges, sharks thrive in this basin, and the researchers aim to unravel the reasons behind their resilience. And given the transboundary nature of the Mediterranean Sea, international collaboration is vital for studying and conserving the animals here.

Led by National Geographic Explorer Dr. Aviad Scheinin from the University of Haifa’s Morris Kahn Marine Research Station, and supported by Dr. Leigh Livne (a postdoc in his lab), the project collaborates with partners across the EMS to combine research and education for long-term conservation outcomes. The Wayfinder grant is crucial to pinpointing the movement and reproduction of sharks and why they return to specific hotspots year after year. “Through National Geographic’s influential platform, we can scale up our story to reach the hearts and minds of scientists, children, and decision makers alike,” Scheinin said. “This is a story about endangered species at the brink, and our ability to discover the secrets about where they are most likely to survive under changing climatic conditions. It can also highlight humanity’s ability to protect and sustain these populations for future generations.”

To date, Scheinin has tagged over 100 sharks, and is leading the Mediterranean’s first “Shark Tagging School” to deploy various state-of-the-art tags to monitor shark distribution. Most sharks have been tagged with acoustic transmitter tags, and his team has deployed a network of 10-15 passive acoustic receivers in areas of known aggregations along the Israeli coastal shelf. The idea for the school originated as a means to bridge the knowledge gap regarding the distribution of Israeli-tagged sharks, fostering a lasting collaboration between Scheinin and his Turkish counterparts. By training fellow shark researchers in safe and ethical catch-tag-and-release practices, the aim is to spread this expertise over the years and extend tagging efforts further west. After carefully building strong collaborations with shark researchers across the eastern Mediterranean, he hopes to unravel the mysteries of the sharks in the EMS. Using a range of minimally invasive satellite tags (including a “Birth Alert Tag” to find parturition grounds of sharks), a network of fixed acoustic receivers, a suite of biological analyses, and the collection of environmental metadata, researchers hope to find where sharks are migrating and residing year-round here.

“Since sharks know no political borders, the researchers’ network of partners is seeking to provide science-based evidence to policymakers with the goal of enacting similar national-level protections for their shark aggregations that already exist in Israel,” National Geographic state in a press release.

According to the IUCN Red List, Sandbar sharks (Carcharhinus plumbeus) are endangered and the Dusky … [+]AFP VIA GETTY IMAGES
To date, Israel stands as the sole country to offer full protection to all elasmobranch species (sharks and rays) within its maritime boundaries. And it here where the study focuses on two specific shark species – the endangered sandbar sharks and data-deficient dusky sharks – both aggregating around the warm water effluent from coastal power stations. According to the IUCN Red List, Sandbar sharks (Carcharhinus plumbeus) are endangered and the Dusky sharks (Carcharhinus obscurus) are data deficient in the Mediterranean Sea and since 2016, Scheinin has been diligently collecting biological, morphometric, and passive acoustic data to assess the well-being and distribution of both these sharks.