Fish: 200 new exotic species in the Mediterranean

Recent research suggests how the Mediterranean is recognized as the most populous sea in the world. It can contain hundreds of new ones exotic species from fish. One wonders what the ecological, social and economic effects of these so-called are fish migrations.

The study shows how the phenomenon has undergone significant acceleration since the 1990s and how the most recent invasions are capable of the most rapid and spectacular geographic expansions. For more than a century, researchers from all Mediterranean countries have documented this phenomenon in the scientific literature, identifying more than 200 new fish species and reporting their catches and their gradual expansion. Thanks to the review of hundreds of these articles and the georeference of thousands of observations, we have been able to reconstruct the ongoing invasion of the Mediterranean. The species of the Red Sea, which entered the Suez Canal (inaugurated in 1869), are the most represented and problematic. However, there are also other important carriers such as ship transport and aquarium unloading. The researchers also looked at the Atlantean origin through the Strait of Gibraltar. Some of these species represent new sources of fish, are well adapted to tropical climates and are already used in the easternmost sectors of the Mediterranean. At the same time, many ‘invaders’ are causing the degradation of natural habitats, drastically reducing local biodiversity and competing with native, endemic and more vulnerable species. The pace of colonization is so rapid that it has already changed the faunal identity of our sea; therefore, reconstructing the history of the phenomenon allows us to better understand the transformation taking place and provides an emblematic example of biotic globalization in the marine environments of the entire planet.

Ernesto Azzurro of Cnr-Irbim and Research Coordinator