Girolata (France) (AFP)

Impressive red cliffs plunge into a turquoise sea: the UNESCO World Heritage-listed Scandola (South Corsica) nature reserve seeks a delicate balance between tourist attraction and preservation of this environmental jewel.

After 40 minutes of sailing from the small port of Porto, this emblematic reserve of the Island of Beauty, created in 1975, appears with 920 hectares of land and 1,000 hectares of marine area.

Sprinkled with greenery, the cliffs of tortured volcanic rocks give a glimpse of figures carved by time that feed the traveler's myths and imagination: here, a horse or hippopotamus head, here Napoleon's hat, further two faces that kiss or even a singer of Corsican polyphony, hand on the ear.

The boat slides close to the "steps of paradise", rocks in the form of stairs that plunge 15 meters deep, before approaching the "pass of misfortune", a former hideout of pirates.

"Breathtaking!", Loose to AFP Irena Snydrova, a Czech tourist came with husband and children.

"It's the magic of nature that draws," says the guide, a bit of poetry, on this boat that leads Czech tourists, Italian, Spanish or French in the Scandola reserve protected by a multitude of labels: nature reserve , Marine Protected Area, Coastal Conservatory, Znieff, Natura 2000, UNESCO World Heritage and European Diploma of Protected Areas.

However, a paradox agitates these still waters: its beauty and its status as a protected site attract more and more people, but this tourist influx harms the ecosystem.

"The reserve is a jewel for Corsica and the Mediterranean but there are several red lights on: the situation of the Ospreys, the state of the Posidonia meadow or the significant reduction in numbers of certain species of fish, including the corb ", details Charles-François Boudouresque, marine biologist at the Mediterranean Institute of Oceanology (IMO) Aix-Marseille University and chairman of the scientific council of the Scandola reserve.

Disturbed "by the current over-crowding during the four months parents raise their chicks", Ospreys or Fish Eagles have "a zero or almost zero reproductive success, with zero or one fledgling chick each year", explains the scientist who points a possible disappearance in 50 years.

- "Hen with golden eggs" -

In view of this, the scientific council recommended in June to prevent any boat from approaching within 250 meters of the nests occupied from April to the end of July. An emergency measure implemented in July and "respected", welcomes Mr. Boudouresque. "It's a good start" that will have to be confirmed next year with four months of application.

Regarding the fall of attendance of the corb in the reserve, the scientific committee has installed underwater sound sensors. "We think it's the noise of the engines of the hundreds of boats present in season" that makes it flee, he says.

For Diego, a crew member of a boat at sea, "it is the presence of hundreds of groupers in the reserve" is rather involved. "They eat everything, including corb," he told AFP.

Divergences of opinion at the heart of the tensions that have pitted for months some professionals of the sea to the conservative reserve, Jean-Marie Dominici, ardent defender of the site targeted by threats.

As for the posidonia meadow, it "is not in an optimal state especially because of the anchors," says Boudouresque.

Wild anchorages that are allowed the day in a part of the reserve. A situation that astonishes Pierre Gilibert, a 65-year-old doctor "in love with Scandola" who thinks "it's strange for a nature reserve to see all these boats, it might be wise to leave access only to professional boats" .

Several boatmen and tourists also believe that private boats are not sufficiently informed and controlled.

"This morning, we still saw people climbing on the rocks, wet in the faults while it is forbidden," regrets Gabriel Pelcot, chief engineer aboard a boat company Nave Va.

His company Nave Va and Via Mare use hybrid boats: the journey is diesel to the reserve and then passes electrically in the site to reduce noise and pollution. An ecological option "30% more expensive", says Gabriel Pelcot who expects nevertheless to see them generalize.

"We must find a compromise between the need to exploit touristically this natural jewel and that of not killing the hen with golden eggs", summarizes Charles-François Boudouresque.

Optimistic, he believes that a general awareness has taken place and advanced solutions to combine tourism and environmental preservation, including the installation of cameras on the nests of osprey to observe without disturbing them.

© 2019 AFP