They seek to protect the orange crocodile

They were discovered in 2008. They can measure up to 1.70 meters. They live in the caves of Abanda, Gabon, for about 3,000 years.

In Gabon, known for its geological diversity and its fauna, the scientists took a big surprise to discover in orange crocodiles, unique in the world, who live among the droppings of bats in the caves.

"When I approached with my flashlight in the cave, I saw red eyes … crocodile in 2008. Two years later, we released a first specimen of the cave and we realized that it was orange ", remember the geoarchaeologist (specialist in archaeological sediments) Richard Oslisly

An extraordinary double discovery that occurred while he and a team of investigators were trying to find remains of human presence in the caves of Abanda, in southern Gabon.

The "Orange Caves Crocodile", which can measure up to 1m70, is unique in the world and has only been seen in the caves of the African country, according to Oslisly.

"At first, we thought that the color could be due to their diet, since we found that these reptiles eat bats orange," says the French researcher.

But after more detailed studies, the scientists presented other hypotheses: a "depigmentation" caused by the lack of light in these caves or the harmfulness of "guano", a substance composed of bats' droppings. mice in which these animals move in all their underground life.

"The urine of bats began to attack their skin and transform their color," says Olivier Testa, spelunker and member of the scientific team.

Oslisly, Testa and American researcher Matthew Shirley have been increasing scientific expeditions since 2010 to better understand these crocodiles.

When mapping the caves, they found four orange crocodiles on about 40 specimens of this species of cave man.

Dozens of "normal" pigments live in nearby caves connected to the surface, says Testa, while orange specimens live in caves accessible only by vertical wells.

– A Presence of 3000 Years –

"We believe that dozens of crocodiles were installed in the caves of Abanda 3000 years ago, which corresponds quite well to a period when the sea level had fallen and this coastal area was back on earth, "says Shirley.

The orange crocodiles were probably trapped in the cave" after entering the hallways when they were small "and not being able to get out of there as they grew, according to Oslisly

Several more or less narrow and interconnected corridors form a network of caves in Abanda and are sometimes inundated by the rising waters of the water table

Shirley argues, however, that crocodiles may have been settled in their cave by their own decision and that they can not be trapped there.

In total darkness, these animals su live in a particular diet, in the caves there are no fish or shellfish, and they feed on bats, grbadhoppers and crickets. "It's a particularly demanding environment," says Shirley.

According to the researchers, these specimens, both orange and those of normal color, belong to the group of dwarf crocodiles "Osteolaemus tetraspis" and are "mutating".

The DNA of these specimens is not sufficiently different from the surface of their dwarf cousin to make a new species, says Shirley, but these animals have developed their own "genetic signature".

Cave crocodiles have, in effect, a unique group of genes pbaded down from generation to generation, scientists have found, comparing blood samples of troglodyte dwelling specimens with those of their dwarf cousins living only on the surface in Gabon

Although the crocodile is already a protected species in Gabon, Oslisly advocates that the caves of Abanda become a "fully protected sanctuary".

"There is still a lot to discover in the caves of Abanda", explains the geoarchaeologist, who hopes to promote "scientific tourism".