The Mediterranean Sea, often seen as a tranquil tourist destination, harbors a surprising resident: the great white shark. These apex predators are present in its waters. While their presence is not as widely recognized as in other global hotspots, scientific evidence and historical accounts establish the great white shark as a component of the Mediterranean ecosystem.
Historical Records and Sightings
Great white sharks have been present in the Mediterranean Sea for centuries. Historical accounts from antiquity, including writings by Herodotus, Aristotle, and Pliny the Elder, describe large predatory fish consistent with sharks. More definitive scientific documentation emerged in the 16th and 17th centuries, with figures like Guillaume Rondelet describing specimens caught off Marseille, and Nicolaus Steno studying a great white shark near Livorno in 1666.
Modern scientific efforts have solidified these historical observations. The Italian Great White Shark Data Bank, established in 1996, has compiled hundreds of records of great white shark occurrences across the Mediterranean. These records, spanning from the Middle Ages to the present, provide insights into their distribution, size, and behavior over time. Confirmed sightings continue to occur despite their elusive nature.
Ecological Drivers of Their Presence
Great white sharks are drawn to the Mediterranean by environmental and biological factors. The sea’s water temperature, typically ranging between 12 and 24 degrees Celsius, falls within their preferred range, allowing them to thrive.
Prey availability is another significant factor. The Mediterranean hosts populations of large bony fish, rays, other shark species, and marine mammals such as dolphins and seals. Historically, seasonal migration of large tuna provided a substantial food source. Scientists confirm the Mediterranean also serves as a breeding and feeding ground for these sharks.
Geographic Distribution and Population Status
Within the Mediterranean, great white sharks are not uniformly distributed but are more frequently recorded in specific “hotspots.” These include the Sicilian Channel, the Straits of Messina, the Ligurian Sea, and the northern Adriatic Sea. The Sicilian Channel, in particular, is considered a significant area, with recent research suggesting it may serve as a nursery ground for juvenile sharks.
Despite their historical presence, the population of great white sharks in the Mediterranean is considered critically endangered. Research indicates a drastic decline in their numbers, with some regional populations experiencing reductions between 52 and 96 percent. Estimating their exact numbers is challenging due to their elusive nature and low density. Ongoing studies, including those utilizing environmental DNA (eDNA) sampling, aim to better understand their current distribution and population trends to support conservation efforts.
Human Encounters and Conservation
Human interactions with great white sharks in the Mediterranean Sea are exceedingly infrequent. Despite their formidable reputation, the probability of an unprovoked attack is very low, far rarer than many common daily risks. While some incidents have been recorded, they are statistically uncommon occurrences.
The great white shark in the Mediterranean faces considerable conservation challenges. Key threats include accidental capture in fishing gear, known as bycatch, and historical targeted fishing. Habitat degradation due to pollution and coastal development also impacts their survival. Overfishing of their prey species further compromises their ability to sustain themselves. Conservation efforts are focused on international cooperation, establishing protected marine areas, and regulating fishing practices to safeguard this vulnerable population.