For more than a decade the DoE has been studying our local shark population on top of the coastal shelf (150ft/30m). Using baited remote underwater video systems (BRUVS), acoustic and satellite telemetry, photo ID, and citizen science, we now have a good understanding of our shark population and how species benefit the Cayman Islands.
Relative abundances and resident behavior of sharks typically fluctuate and change throughout the year and over time. Sharks have long generation times due to their slow growth, late maturity, long pregnancies and relatively few young per litter. Hence for real changes in shark populations to occur naturally it takes a long time and it can take decades for real changes in population numbers to become evident. The ongoing monitoring by various methods is critical for the continued protection and conservation of sharks within Cayman waters.
The Cayman Islands lie adjacent to the Cayman trench, the deepest trench in the Caribbean Sea. And our three islands are the tips of the Caribbean ridge, an underwater mountain chain that runs parallel to the trench. So there is a lot of deep water surrounding us, yet little is known of Cayman’s marine life below 150ft/50m. As we feel the effects of climate change and the increase of the human population, one key question is whether Cayman’s deep waters offer a possible refuge from climate change and human disturbances?
Using deep-water baited remote underwater video systems (BRUVS), baited seabed landers, and environmental DNA (eDNA), this project surveys Cayman’s underwater environment down to 6500ft/2000m. Focusing on commercial fish species, such as groupers and snappers, and especially threatened species such as sharks, the project aims to map the distribution of deep-water coral and other biotopes, to further understand how shark populations use the deep, and evaluate connectivity between shallow-water and deep-reef communities.
The Cayman Islands | Deep Sea Research