Gambier Islands, 4 new species of coral


30 June 2011

Tara has adopted her ‘coral rhythm’. Finished the long distances of the preceding leg between Guayaquil (Ecuador) and the islands of French Polynesia. We are now almost sedentary, staying for 2 weeks in the lagoon of the Gambier Islands.

From our mooring, each day 2 pneumatic boats take Francesca, Connie and the 2 Erics to a diving site, one in the morning and a different one in the afternoon. The divers jump into the water equipped with a burin and net for collecting samples of coral, and a camera to photograph the sampling site and coral in situ. For an hour they crisscross the ocean floor at depths varying between 10 and 15 meters.

Metallic hammering noises echo underwater, and a long column of bubbles rises from each diver. In the zodiacs, Mathieu and Julien keep an eye on their progression.

After an hour, heads emerge from the water. Mathieu takes care of the diving tanks. “Find anything interesting?” “It looks very much like this morning’s site,” says Francesca, “But nothing like what we saw the first day, where there was a lot of dead and damaged coral. Here it’s very much alive and very beautiful!” “And we had another visit of a small black spot,” she says smiling. The lagoon’s little sharks seem curious about the scientists’work and swim by to observe them, but without showing their teeth for now.

In 1974, the biologist Jean-Pierre Chevalier made a study of Gambier Island coral and inventoried 54 species, a collection conserved at the Museum of Natural History in Paris. “It’s fantastic to be here and pursue my work! Since Sunday I’ve already found 4 new species! So we’re now up to 58!” Francesca’s radiant smile communicates her energy.

Eric Béraud brought up a big block of porites, a kind of coral — 40 kilos on the deck that will allow us to study the history of the lagoon. “Porites grow 1 cm per year, so this 40 cm block will tell us about events of the past 40 years. Like a glacial carrot, or the cross-section of a tree-trunk, it will give us information on the evolution of the ocean’s state-of-health.”

Eric Roettinger, nicknamed “Kahikai”, is in charge of imagery. He goes collecting specimens, then brings them aboard the boat. The ‘science table’on the deck is where he sets up his photo studio, just like a portrait studio, but in miniature. The only real difference is that the models measure only a few centimeters and pose in aquariums. A uniform backdrop and 2 lateral lamps, and Kahikai is ready to shoot. “Could you turn over the jellyfish with the pipette? That way the tentacules will be more visible.”

The elegant, translucent creature continues its pulsations and dances beneath the lights. Night has fallen and it’s gotten cool, but Kahikai stays cosy under his cap, and continues taking pictures through the night.

Hervé Bourmaud, the captain went to Mangareva in the hope of buying some fuel, but returned empty-handed. Hazards of island life, the Nuku Hau, the boat we’ve been expecting for 2 days, has still not arrived. “The one who advances in peace” takes her time and wears the name well.

Tomorrow Tara will change moorings with 2 days scheduled around Taravai, island west of the lagoon. Stationed in the shelter of this island, we’ll be protected from the “noirot”, wind of 25 knots forecast for the coming days.

Sibylle d’Orgeval