The Mediterranean's Great White Shark: A Rare Encounter and a Growing Threat
The recent discovery of an adult great white shark in the Mediterranean by volunteer technical divers has sparked excitement and concern. Derk Remmers, a volunteer technical diver and head of Ghost Diving's German chapter, captured the first-ever underwater footage of a great white shark in its natural habitat in the Mediterranean. This rare encounter, while scientifically valuable, was overshadowed by the more pressing issue of ghost nets, a silent killer lurking in the depths.
The Strait of Sicily, a heavily exploited fishing area, was the site of the discovery. The shipwreck targeted by the divers had accumulated ghost nets, a threat that extends far beyond any single wreck. Ghost nets, made to kill fish, continue to trap and kill marine life indefinitely, even when not attached to fishing boats. The divers' mission, organized by the Healthy Seas Foundation, Ghost Diving, and the Society for Documentation of Submerged Sites (SDSS), aimed to clear the ghost nets and recover sections of net, which will be safely discarded or recycled.
The scale of the problem is staggering. Between one to ten percent of all fishing gear from fishing vessels worldwide gets lost every year, adding up to more than half a million tonnes annually. This lost gear poses a significant threat to the marine ecosystem, as it traps and kills marine life, including large fish species and loggerhead sea turtles. The presence of the great white shark in the Strait of Sicily serves as a stark reminder of the scope of this threat, which echoes through the entire marine food web.
Derk Remmers emphasizes that volunteer clean-up operations alone cannot solve the ghost net crisis. While these efforts are valuable, they are limited in scope. The real solution lies in confronting illegal and large-scale industrial fishing head-on. Family-run fishing businesses have strong incentives to prevent gear loss, but it is industrial and illegal actors operating at scale who pose the greatest threat to the ecosystem. Derk urges humans and Europeans to enable politicians to work against this threat and be more cautious about their underwater environment.
The mission also included environmental DNA sampling and underwater monitoring to improve understanding of the species present around the wreck. Further analysis is expected in the coming months, with additional footage and scientific material to be released. The rare encounter with the great white shark highlights the importance of addressing the ghost net crisis and the need for a comprehensive approach to protect the Mediterranean's fragile marine ecosystem.
