Good news has emerged from a long-term study at the Leon H. Charney School of Marine Sciences at the University of Haifa: the coast between Ma’agan Michael and Dor Beach serves as a vital nursery for the endangered black guitarfish (Rhinobatos cemiculus). The study, led by PhD student Eynav Cohen and her colleagues, shows that this area provides essential support for early life stages for these cartilaginous predators. According to Cohen: “A nursery is a natural area where animals, especially marine species, congregate during the early stages of life. A nursery is defined as an area that increases an animal’s chances of survival during the sensitive early stage of life by providing optimal conditions in terms of food, protection against predators and shelter from extreme environmental conditions. After the findings of the study, we hope that this area will be declared a nature reserve when the young guitar fish are gathered here, so that they can be protected.”
Globally, guitarfish populations are in a constant state of decline, with the Mediterranean Sea particularly affected, mainly due to net fishing pressures. The International Union for Conservation of Nature has classified the black guitarfish as critically endangered, underscoring the urgency of conservation measures. In 2017, NOAA Fisheries listed the species as threatened under the Endangered Species Act. One of the main challenges in understanding and protecting these fishes is the limited biological and ecological knowledge available, especially regarding their population size along Israel’s coastline and around the world. Most existing data derive from commercial fishing activities, which do not provide a comprehensive picture of species health or distribution.
Published in Frontiers in Marine Science and funded by the Blue Marine Foundation, this new study was conducted at the Morris Kahn Marine Research Station at the University of Haifa. The initiative started with research student Barak Azrieli from the non-profit organization Sharks in Israel during his Master’s program and was supervised by Dr. Aviad Scheinin and Professor Dan Tchernov. This marked the creation of the first guitarfish monitoring program in Israel; after Azriel’s basic work, Cohen, along with Dr. Leigh Livne, Dr. Scheinin and Professor Tchernov, continued work with the goal of advancing conservation efforts and ensuring recognition of the Ma’agan Michael coast as a nursery site for blackchin guitarfish.
However, in order to succeed, the researchers had to meet three specific criteria established in 2007 by Dr. Michelle Heupel. The first criterion requires that juveniles of the species in question are found in higher concentrations in the proposed nursery area than in the surrounding regions. The second? It stipulates that these young cartilaginous fish must continue to use the area for long periods, especially for two weeks. Finally, this phenomenon has been observed consistently over many years.
Researchers began conducting preliminary visual surveys along the coast of Israel in 2017, finding that the concentration of juvenile guitarfish at Ma’agan Michael is significantly higher than that of the adjacent coast near Caesarea, thus meeting the first criterion. Surveys also indicated a strong presence of juvenile terns from late August to early November. Boom, which fulfills the second necessary criterion for this designation. And thanks to continued monitoring efforts over the past few years, researchers were able to meet the third criterion by consistently documenting these patterns over multiple seasons.
With this research providing strong evidence that the coast at Ma’agan Michael functions as a nursery for black guitarfish, the team is optimistic that their findings will prompt regional and national regulatory bodies to declare the area a marine nature reserve during the time when the juvenile guitarfish are collected. With this designation, not only would the current juveniles of the species be protected, but the designation plays a crucial role in broader efforts to conserve this endangered fish and its habitat. Protecting the garden is an essential step towards securing the future of the black guitarfish… now will those responsible take it?