ECOLEGACY MEDITERRANEAN
Invasive Species in the Mediterranean
The Mediterranean Sea has been undergoing a significant ecological transformation in recent years due to the rapid increase of invasive species. A large proportion of these species have entered the region from the Red Sea via the Suez Canal, through a process known as Lessepsian migration. Rising sea temperatures on a global scale have further facilitated the establishment and rapid spread of these tropical-origin species in the Mediterranean.
The expansion of these species is not solely a biological process. Increasing sea temperatures, habitat loss, and human activities are accelerating the transformation of the Mediterranean into a more suitable environment for tropical species. For this reason, addressing invasive species requires holistic approaches that also focus on maintaining the overall health of marine ecosystems.
Today, hundreds of non-native species have been recorded in the Mediterranean. Among them are lionfish (Pterois miles), silver-cheeked toadfish (Lagocephalus sceleratus), rabbitfish (Siganus rivulatus and Siganus luridus), dwarf pufferfish (Torquigener flavimaculosus), blue crab (Callinectes sapidus), and various tropical shrimp and mollusc species. Some of these species are able to rapidly increase in number due to their strong predatory behavior, high reproductive capacity, or intensive grazing habits, often outcompeting native species.
The impacts of invasive species are not only ecological; they can also directly affect fisheries, tourism, and coastal economies. For example, some species alter fish stocks, while others pose risks to human health due to their toxic nature. However, the spread of invasive species is rarely driven by a single factor. Rising sea temperatures, habitat loss, coastal development, pollution, and overfishing all accelerate this process.
For this reason, invasive species should be addressed not only in terms of newly introduced organisms but also in relation to the overall resilience of Mediterranean ecosystems. Healthy seagrass meadows, balanced fish populations, and well-protected coastal habitats enhance the ability of ecosystems to withstand these changes.
Lionfish - Pterois miles
A predatory fish of Red Sea origin, equipped with venomous spines. It feeds on small fish and crustaceans. Due to the lack of natural predators and its rapid reproduction, it is spreading quickly in the Mediterranean and can significantly impact native fish populations.
Silver-cheeked Toadfish - Lagocephalus sceleratus
A highly resilient species with strong teeth. It contains a potent neurotoxin called tetrodotoxin, making it extremely dangerous for human consumption. It can damage fishing nets and have significant economic impacts on local fisheries.
Rabbitfish - Siganus rivulatus & Siganus luridus
These herbivorous species feed primarily on algae. When their populations reach high densities, they can overgraze algal and plant communities in coastal ecosystems, leading to the formation of “barren rocky” areas.
Blue Crab - Callinectes sapidus
A fast-moving crab species capable of spreading over wide areas. It exhibits both predatory and opportunistic feeding behavior. While it has become a new economic resource for fisheries in some regions, it can also compete with native benthic species.
Dwarf Pufferfish - Torquigener flavimaculosus
Known for its inflatable body and strong teeth, this species has powerful jaws capable of crushing hard-shelled prey such as crustaceans. It plays a predatory role within the ecosystem and, in some areas, can exert pressure on native species.
Red Sea Goatfish - Parupeneus forsskali
The Red Sea goatfish (Parupeneus forsskali) is a species originating from the Red Sea that has been increasingly observed in the Mediterranean in recent years. It entered the Eastern Mediterranean through Lessepsian migration via the Suez Canal and has a strong potential to spread rapidly, particularly in warm, nearshore habitats.