[LUM#3] Coral Reefs in Danger
They are under threat all over the world. How can we better protect coral reefs, those irreplaceable havens for marine life? A scientific expedition offers some new insights.
New Caledonia, the Tonga Islands, French Polynesia: this isn’t a list of idyllic destinations for your next vacation, but the research sites for the Pristine project. In these dream islands, home to some of the planet’s last remaining ocean refuges, a team of marine biologists has dived to explore the teeming marine life. Their goal: to assess the health of coral ecosystems.
Protecting marine life
Because these havens of life are in danger.“The latest scientific reports are alarming: 75% of the world’s coral reefs are currently under threat, with 60% facing a direct and immediate threat. By 2050, that figure will rise to 100%,” warns David Mouillot of the Marbec laboratory.
To protect marine life, we first need to understand it.“The value of near-pristine sites lies in their ability to serve as a baseline: they allow us to assess the state of biodiversity in the absence of any human intervention.” This baseline will then serve as a benchmark for measuring the impact of human presence around the world, as well as for evaluating the effectiveness of marine protected areas.
While diving off the Actéon Islands in Polynesia, the Minerve Reefs in Tonga, and the archipelago of New Caledonia, the researchers were in for quite a surprise. Beneath the waves of the Pacific, they witnessed a forgotten spectacle…“Sharks in abundance, gigantic groupers, Napoleon fish, humphead parrotfish: a teeming life animates these ocean depths. Some species that are thriving here are on the brink of extinction elsewhere,” describes David Mouillot.
An extraordinary biomass: more than one ton of fish per hectare. That’s roughly 70% more than what is found in other protected areas around the world. The difference is striking. Why this explosion of life? Or rather, why are fish so scarce in other protected areas?
All too human
For scientists on the Pristine project, the answer is clear: human proximity is responsible for the disappearance of fish. This is a factor they have carefully measured.“Coral reefs are closer to humans than we thought. Half of the world’s reefs are located within a 30-minute drive of a village, a market… Reefs that are therefore under intense pressure. As a result, 90% of the large predators—tuna and sharks—have disappeared from these areas.”
Only reefs located far enough away from human communities would be safe, according to the study, which estimates the critical threshold to be around a 12-hour journey. However, such reefs are now very rare.“Globally, barely 1% of coral reefs are located in safe havens—that is, more than 12 hours’ travel away. This is the study’s other major finding: the scarcity of these natural refuges. They are found primarily in the middle of the Indian Ocean and in the Pacific.”
Western countries bear the responsibility for protecting these areas, which are vital for biodiversity. This is because most of these remaining havens for marine life belong to the United Kingdom, the United States, and France: New Caledonia alone accounts for a quarter of the world’s isolated reefs…
Biodiversity that is inadequately protected
This is a particularly heavy responsibility, given the state of decline in marine biodiversity. While marine protected areas exist all over the world, their effectiveness is partly called into question by the findings of the Pristine project.“These areas are useful, particularly for allowing small marine life to rebuild its populations. But they are insufficient. They do a poor job of protecting certain species, especially large predators.” The main problem is their proximity to human activity. Their size is also an issue: too small, they do not cover the entire vital range of threatened species.
While efforts are currently being made to establish new protected areas, David Mouillot argues that they remain woefully inadequate. This is especially true given the tendency to establish these areas as far away as possible from zones where conflicts of interest might arise with coastal users—such as fishermen and tourists.“Public authorities are thus creating reserves in locations that do not really require protection,”the researcher summarizes.
Government officials who are, moreover, poorly informed and sometimes unaware of the value of a natural heritage that is, after all, irreplaceable.“As scientists, we have a role to play in informing and raising awareness to shift policy.” This approach can prove effective: in New Caledonia, following the implementation of the Pristine project, the Entrecasteaux reefs were designated a protected area.
What solutions are there to protect marine life?
Ask all the countries involved to make a greater commitment?“It’s hard to ask developing countries to make additional sacrifices. How can we deny access to the sea to villages that depend on fishing for their livelihood? On the other hand, industrialized countries must implement strict protection measures within their own territories.”
What kinds of protection?“Create ‘No Entry’ zones where access will be prohibited. Or even flip the logic, by designating specific areas where fishing is permitted, and automatically designating the remaining areas as protected zones. An experiment that could prove successful on a regional scale—why not New Caledonia or Corsica, which could serve as examples? And demonstrate that fishermen themselves will ultimately benefit from these measures, which alone are capable of rebuilding fish stocks.”
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