When Climate Erases the Memory of the Coast...

The Mauritian coastline is facing the impacts of climate change: erosion, salinization, bleached reefs, and a threatened coastal memory. These disruptions weaken communities and their livelihoods. An overview of the observations and solutions needed to build a fair relationship between Mauritians and their sea.

Iconic beaches like Flic-en-Flac and Le Morne are receding by several meters. Coral reefs are repeatedly bleaching. Agricultural land is becoming sterile due to salt. Climate change is no longer an abstract threat in Mauritius; it is reshaping the landscape before the eyes of residents, jeopardizing the tourism economy and the very identity of coastal communities.

In response to this urgent crisis, scientists, policymakers, and associations have decided to take action. Recently gathered at the Blue Policy Strategy Forum, they aim to bridge a dangerous gap: the one that separates scientific knowledge from political decision-making.

'"Mauritius's future depends on our ability to translate science into concrete actions,' summarizes Dr. Jay Doorga, a lecturer at the University of the Mascarenes, author, and consultant trained at the University of Oxford. With over 50 publications and a book, he actively contributes to African policies on energy and climate.

In just a decade, the phenomenon has severely accelerated. What was once a slow natural process has become a visible threat. Sea levels are rising faster. Waves are hitting harder. As a result, at emblematic sites like Flic-en-Flac or Le Morne, the coastline has receded by several meters.

But that's not all. The corals, those natural barriers that protect the island from waves, are dying. As water temperature rises, they bleach and become fragile. Mangroves, the forests that absorb storm shocks, are gradually disappearing. Furthermore, rampant coastal urbanization exacerbates the situation.

To accurately assess the extent of the damage, the University of the Mascarenes has secured international funding. The goal is to map erosion and propose concrete solutions to authorities. For while signs of climate change are everywhere, precise data is still lacking.

In addition to beach erosion, another insidious phenomenon is eroding the island: the salinization of agricultural land. The mechanism is simple but relentless. Underground, freshwater aquifers normally float above saltwater, which is denser. But this fragile balance is breaking down.

On one side, rising seas push salty water inland. On the other, farmers extracting too much freshwater create a vacuum that allows seawater to fill. The consequence: salt rises in the soil, accumulates at the roots, and renders the land barren. In coastal plains, some fields have already been abandoned.

These losses have yet to be fully quantified, but researchers are working hard on it. The stakes are high: Mauritius needs to know which lands are doomed and which can still be saved.

Will entire villages need to be relocated? This explosive question is now openly posed. Are some coastal neighborhoods, some fishing villages doomed to disappear? Ongoing research aims to identify, with maps, the areas most threatened by flooding and erosion. "These areas may ultimately require adaptation strategies, including relocation," Dr. Doorga cautiously acknowledges. This topic is sensitive as it affects the most vulnerable: fishing communities, residents of neighborhoods built recklessly near the shore, and those whose lives depend entirely on the sea.

These populations suffer a double blow: they lose their homes and land, yet often lack the means to adapt or relocate. Fishermen are witnessing dwindling fish stocks as coral dies. Farmers watch their fields perish under salt. And everyone worries about tomorrow.

Beyond material losses, a collective memory is fading with the coastline's retreat. Elders recount how the beach once stretched, where the best fishing spots were, and where old paths lay. But these landmarks are becoming unrecognizable. "The retreat of the coast erases historical markers and ancestral land boundaries. It is also a cultural and social memory that disappears," explains Dr. Doorga. For coastal communities, this loss of identity makes psychological adaptation even more challenging. How can one get used to a landscape that is changing faster than generations?

Yet this elder memory is not mere nostalgia. It holds valuable information: where seagrass once grew, how currents flowed, how the coastline evolved long before scientists began measuring it. Integrating traditional knowledge with modern data allows for better analyses and solutions that are more acceptable to populations.