Tourists threaten Mauritius coral reefs

Julia Hinde marks World Oceans’ Day with a trawl of marine research

Tourism in the tropics may be killing the very thing which is its life blood, say marine biologists from the University of Wales, Bangor.

Scientists from the north Wales institution spent more than eight years studying the coral reefs surrounding the tropical island of Mauritius.

Their work paints an alarming picture of coral destruction.

According to John Turner, lecturer at the university’s school of ocean sciences, satellite images of the island’s coastline taken in 1990 and 1997, and on-the-ground marine observations, reveal large sections of coral “degraded and broken”.

Dr Turner, who is working with a team of researchers from the University of Mauritius who trained at Bangor, believes this decline in coral life can be attributed to natural impacts such as cyclones. However, he said industrial effluent, sewage, agriculture and tourism have also taken their toll.

Fertilisers used to grow sugar, the mainstay of the Mauritian economy, are washed into coastal coral-filled lagoons and are promoting algae growth, Dr Turner said.

The algae darkens the water and as corals rely on light to feed, their growth is impaired.

The coral is also broken up by tourists diving and snorkelling. The dredging of the sea bed for sand to build hotels disturbs the organisms as well. “Everything is competing against the corals,” Dr Turner said.

“We are trying to discover what are natural changes, and what are caused by man.”