Tropical fish and corals are not adequately protected
A recent study shows that the global network of marine protected areas is insufficient to preserve the biodiversity of corals and tropical fish.
Marine life is threatened by human activity: we already knew that. Fortunately, “marine protected areas” are being established all over the world. There are currently 3,625 such areas on coral reefs, covering a total area of 942,568 km² (or 5.9% of the world’s coral reef area). These areas, where human activities are regulated, serve to protect nature and provide refuges for ecosystems and their biodiversity.
“Trees of Life” that have been only partially preserved
But is this really true for biodiversity as a whole? When it comes to fish and corals, the verdict is in: on a global scale, many species are reportedly insufficiently protected by these sanctuaries. In an article published in Nature Communications on January 12, researchers from the University of Montpellier, IRD, EPHE, and CNRS demonstrate that the global network of marine protected areas is insufficient to conserve the genetic diversity of corals and tropical fish. This diversity is essential for maintaining the long-term functioning of coral ecosystems.
The international team of researchers led by David Mouillot, a professor at the University of Montpellier and at UMR MARBEC, studied the geographic distribution ranges of 805 coral species and 452 fish species and examined their coverage by the global network of marine protected areas. They examined the level of protection afforded to the “tree of life”—that is, the genetic diversity—of these species. The result: only 1.7% of the coral tree of life and 17.6% of the fish tree of life meet the minimum coverage thresholds required by protected areas to ensure their preservation.
Poorly distributed areas
“Marine protected areas only protect closely related species—that is, those belonging to the same families. Other families of species receive little or no protection,” summarizes David Mouillot. The reason is simple: in the absence of a comprehensive conservation strategy, marine protected areas are distributed very unevenly across the globe. While they are abundant around Europe, or between Australia and New Caledonia, for example, there is a significant shortage in the Global South, particularly in the Caribbean and Africa.
These disparities often reflect economic development inequalities, but also political will: in the Northern Hemisphere, and in developed countries with a strong environmental commitment, conservation efforts are substantial, whereas in the South, some countries lag behind in implementing actions.“We must refocus the creation of protected areas on priority zones: regions with high concentrations of ancient, poorly protected lineages that are highly exposed to human activities, particularly in the Atlantic, the Southeast Pacific, and the Indian Ocean,” states David Mouillot.“To preserve genetic heritage and ecosystem functioning, protected areas must now incorporate the evolutionary history of species into their objectives.”