The Mediterranean Sea has been a popular tourist destination for decades, with a rich history and striking landscapes drawing worldwide visitors. More than just a postcard-worthy backdrop for a holiday, the Mediterranean has been at the center of civilization for millennia as a vital trade route and provider of sustenance to its many nearby inhabitants. Bordered by Europe, Africa, and the Middle East, evidence of the trade and conflict is underwater; fascinating shipwrecks draw scuba divers to destinations including Malta and Cyprus.

Historical Connections

Human activity has a lasting impact on our planet, as evidenced by the evolution of the Mediterranean Sea and its inhabitants. When the Suez Canal was completed in 1869, the Mediterranean opened to the rest of the world, enabling a more efficient trade flow into and out of Europe. While these changes had a visible impact topside, they also affected the underwater world, with marine animals following container ships as they traveled between the established ecosystems of the Red Sea and the Mediterranean.

The warmer waters and higher salinity of the Red Sea provide a robust environment for diverse marine species to thrive. As such, the most common migration of marine life is from the Red Sea to the Mediterranean, known as the Lessepian Migration. Over 300 species have migrated to the Mediterranean, resulting in substantial changes to its ecosystem. The most notable of these is the infamous lionfish.

A Beautiful Invasive Species

Divers are familiar with the striking beauty of the lionfish, decorated with feather-like spines renowned for their painful poison. The fish are endemic to many parts of the world, including the Indo-Pacific and Red Sea, and are routinely spotted when diving or snorkeling in these regions. What happens when a rapidly reproducing poisonous fish enters a new ecosystem? When lionfish were accidentally introduced to the Western Atlantic and Caribbean, they rapidly became the region’s most invasive species. Female lionfish produce 2 million eggs per year and spawn every four days. This incredible reproduction rate in areas with no natural predators has led to a robust population of problematic fish. Lionfish threaten the entire reef ecosystem and ocean by feeding on smaller, juvenile reef fish.

If a lionfish invasion has been so detrimental in the Caribbean that it has inspired lionfish hunting courses, what hope does the Mediterranean have? Interestingly, although the Lessepian Migration began with the completion of the Suez Canal, Lionfish have only become a problem in the Mediterranean in recent years due to rising water temperatures. The European Commission raised the alarm about lionfish in 2015, resulting in efforts to learn from scientists involved in lionfish removal in the Western Atlantic. However, there have been few efforts to report on the Mediterranean lionfish invasion, leading the Underwater Photography Guide’s Editor-in-Chief, Nirupam Nigam, to visit the region to find out first-hand how substantial the problem is.

A Diver’s Startling Discovery

In the summer of 2022, Nirupam packed up his dive gear and traveled to the Turkish Riviera to dive into the waters of the Lycian coast to see what he could discover. The small town of Kas is the hub for scuba diving in Turkey, and where Nirupam ventured out on a dive boat to plunge into the crystal-clear Mediterranean waters. The first dive site met his low expectations and featured mostly lifeless dramatic topography. With a history of fishing dating back centuries, Nirupam anticipated that the Mediterranean would have few fish and discovered that he was correct; the only place he had seen fewer fish was in the Gulf of Maine.

As he continued to descend, Nirupam noticed “small, dark, basketball-sized shadows” emerging from the depths. He approached them as they hovered in the blue; he recognized familiar spines and striations of lionfish and was shocked to see numbers in the dozens. The fish turned and flared their spines in warning. Some lionfish curiously approached their reflections in the dome of his underwater camera.

As the group continued their dive, Nirupam realized there were lionfish everywhere; it was a dramatically different situation from the invasion in the Caribbean. Lionfish appeared to be the primary marine species in the waters around Kas. Rather than an invasion, this was more like a replacement.

Conclusions

Divers bear witness to the constantly changing and adapting ecosystems in our oceans and can have a significant impact by documenting and sharing their stories with others. Although Nirupam did only a few dives in a small region of the Mediterranean, even anecdotal evidence of a profound lionfish invasion is enough to consider its ramifications.

How can we help reset the scales and right this imbalance in the Mediterranean Sea? Scuba divers and free divers can help create programs to cull and eat lionfish, as they have done in the Caribbean. Establish fisheries to capture lionfish in the Mediterranean and provide an excellent source of protein to the region. However, it is complicated, if not impossible, for humans to effectively intervene in an ongoing invasion through the Suez Canal. Time will tell how the lionfish invasion will affect the Mediterranean Sea; as Jeff Goldblum’s character Dr. Malcolm in Jurassic Park says, “Life finds a way.”

About the Author

Top photo: DepositPhotos, rest copyright Nirupam Nigam.