Unraveling The Secrets Of Mediterranean Sharks

The University of Haifa researchers have been awarded a significant $100,000 grant from National Geographic Wayfinder for an innovative study tracking shark movement in the eastern Mediterranean Sea (EMS). The EMS is known for its diverse marine life, including fish, invertebrates, corals, marine mammals, and seabirds. Despite facing climate change challenges, sharks thrive in this region. The researchers aim to uncover the reasons behind their resilience. Collaborating with international partners is essential for studying and conserving these remarkable animals.

Dr. Aviad Scheinin, a National Geographic Explorer from the University of Haifa’s Morris Kahn Marine Research Station, leads this project in collaboration with Dr. Leigh Livne, a postdoc from his lab. Together, they are partnering with various organizations in the EMS to conduct research and education activities with the aim of long-term conservation. The Wayfinder grant is essential for understanding shark movement, reproduction patterns, and why they return to specific areas year after year. Scheinin explains, “Through National Geographic’s influential platform, we can share our findings with scientists, children, and decision-makers alike. This is a story about endangered species on the brink and our ability to uncover the secrets of their survival under changing climatic conditions. It also highlights humanity’s potential to protect and sustain these populations for future generations.”

So far, Scheinin has tagged over 100 sharks and established the Mediterranean’s first “Shark Tagging School” to deploy state-of-the-art tags for monitoring shark distribution. Most sharks have been tagged with acoustic transmitter tags, and the team has deployed a network of 10-15 passive acoustic receivers in areas where shark aggregations are known to occur along the Israeli coastal shelf. The Shark Tagging School aims to bridge the knowledge gap regarding the distribution of Israeli-tagged sharks and foster collaboration between Scheinin and his Turkish counterparts. By training fellow shark researchers in safe and ethical catch-tag-and-release practices, the goal is to expand tagging efforts further west in the future. Through the use of minimally invasive satellite tags, fixed acoustic receivers, biological analyses, and collection of environmental metadata, the researchers hope to uncover the year-round migration and residence patterns of sharks in the EMS.

“Since sharks do not recognize political borders, our network of partners aims to provide science-based evidence to policymakers, advocating for national-level protections for shark aggregations in the EMS, similar to those already established in Israel,” states National Geographic in a press release.

Israel currently stands as the only country that offers full protection to all elasmobranch species (sharks and rays) within its maritime boundaries. The study focuses on two specific shark species found in Israeli waters – the endangered sandbar sharks and data-deficient dusky sharks. Both species aggregate around warm water effluent from coastal power stations. According to the IUCN Red List, sandbar sharks (Carcharhinus plumbeus) are endangered, and dusky sharks (Carcharhinus obscurus) have insufficient data available in the Mediterranean Sea. Since 2016, Scheinin has been dedicated to collecting biological, morphometric, and passive acoustic data to evaluate the well-being and distribution of these shark species.

The grant will support the researchers’ efforts to address crucial questions such as “Why do these two shark species use warm water havens from the effluent waters of Hadera power plant cooling water in winter?” and “Where do they go in the summer months?” The EMS serves as a model for other marine regions and offers valuable insights into species’ requirements amidst the escalating impacts of climate change. This study provides a unique opportunity to study the various habitats in the EMS, which exist in a “post-warming” state, and gain a better understanding of the evolving dynamics of marine life in response to changing environmental conditions.

Another essential aspect of the study is conservation physiology led by Dr. Livne. This part focuses on investigating the fecundity and maternal condition of sharks, utilizing hormone and blood biochemical markers, as well as ultrasonography. As part of the Israeli shark tagging team since 2019, Livne assists Scheinin in catch-and-release training and on-board sampling, as well as analyzing the data for meaningful conclusions that will contribute to the conservation of both species. Livne highlights the significance of changing the public’s perception of sharks from being perceived as threats to being recognized as essential stabilizing forces within marine ecosystems. She explains, “The portrayal of sharks as dangerous is often sensationalized. In the 70s and 80s, when the movie Jaws was released, the idea of sharks as predators dominated conversations. However, the public is now learning more about what scientists have been emphasizing for decades – that sharks play a crucial role in our ecosystem. They are stabilizing forces critical to maintaining ecological balance in marine life.”

The ultimate goal is to explore whether the insights gained from this study can be extrapolated and applied to benefit other species around the world.

Denial of responsibility! TechCodex is an automatic aggregator of the all world’s media. In each content, the hyperlink to the primary source is specified. All trademarks belong to their rightful owners, and all materials to their authors. For any complaint, please reach us at – [email protected]. We will take necessary action within 24 hours.