As part of our long-term ecological monitoring work, we are constantly searching for potential sites of interest, especially at depths that require the skills of our technical diving team. In October 2019, we conducted a first impression dive at a site of interest in Achziv at 85 meters depth. Prior to the actual dive, we collaborated with other scientists to identify a suitable site that meets our needs. For this survey, we searched for a site with rocky substrate until 100 meters depth, much deeper than our usual dives to 45 meters. Why rocky substrates?
As part of our long-term ecological monitoring work, we are constantly searching for potential sites of interest, especially at depths that require the skills of our technical diving team. In October 2019, we conducted a first impression dive at a site of interest in Achziv at 85 meters depth. Prior to the actual dive, we collaborated with other scientists to identify a suitable site that meets our needs.
For this survey, we searched for a site with rocky substrate until 100 meters depth, much deeper than our usual dives to 45 meters. Why rocky substrates? Rocky substrates allow for the establishment of complex marine communities as they provide a stable anchor to grow on. In order to find such sites, Dr. Itzik Markovsky (University of Haifa) and Dr. Mor Kanari (IOLR) provided us with high-resolution maps of the seafloor and their analysis allowed us to identify a point particular interest.
On the day of the dive, an ROV loaded with cameras from Prof. Jonathan Belmaker’s lab (Tel Aviv University) was lowered in order to confirm that the location was ideal and that conditions were safe for diving, with no strong currents. Despite the poor light conditions at 100 meters, visibility at this point was good, allowing us to conduct the survey.
What we discovered was an oasis of life. While the surrounding area is characterized by soft bedding, this point indeed had a rocky substrate, allowing for a wealth of species to establish themselves in this habitat. The site had a rich variety of invertebrates. While most of the organisms were sponges, there were also corals, sea urchins, hydrozoans, and more. The ROV was able to capture on video very large fish while the divers observed smaller fish. Interestingly, all invertebrates and fish observed were native species, and no invasive species were observed.
These rocky sites in deeper waters provide a unique habitat for animals that are observed only at these depths. Such sites may be serving as a refuge for animals impacted by anthropogenic changes in conditions in shallow water, such as warming. With little research so far conducted in these areas, it is important to continue to study them in order to increase awareness and protect it in the future.