Warming waters, maritime traffic, canals: the Mediterranean is seeing the arrival of species from elsewhere. Some settle in and upset the local balance.
What are we talking about?
An invasive species is an introduced species that proliferates at the expense of local fauna and flora. In the western Mediterranean, the blue crab is being observed and reported more and more often in the Gulf of Lion; others, such as the lionfish, are being closely monitored.
Why it matters
These species can compete with or prey on local wildlife, alter habitats and affect fishing. Knowing them better means being able to react early.
The role of divers
Divers are invaluable sentinels: a photo, a location, a report to scientists all help track the spread of these species. On the Côte Vermeille, the Cerbère-Banyuls marine nature reserve (created in 1974, France’s first marine reserve, around 650 hectares) offers a setting where this watchfulness makes perfect sense. It is one of the concrete forms of citizen science.
Talking about it at MERveille
Workshops and talks will help you recognise these species and understand how everyone can contribute to monitoring efforts.
If you spot one, do not handle an unfamiliar species (some are venomous): photograph it and report it to the relevant scientific bodies.