My stay in Mauritius and Rodrigues lasted two months and a few days. On my return to France, I wanted to share with the members of S.O.S Big Blue my experience and adventure with marine mammals.
Introduction
The team settled in a house by the sea, in "La Preneuse", a small neighborhood in the village of "Black River" in the southwest of Mauritius. I accompanied a scientist and future ketologist.
History:
Mauritius was discovered by the Portuguese around 1510 and Tristan da Cunha named it "Cirne", the island of the Swan, after one of the ships in his fleet or the strange bird he saw: the "dodo", which became the national emblem. It was occupied in 1598 by the Dutch who called it "Maurice", after their prince. In 1715 the French took possession of the island and Mahé de Labourdonnais made Port-Louis a trading post of the Indies. But after many naval battles with England, France gave up its island and the crown gave it back the name of "Mauritius". Mauritius gained its independence in 1968 and became a republic on March 12, 1992. Its constitution is based on the "Westminster" model (a prime minister and his cabinet exercise executive power) and the Napoleonic code is still in force.
Geography:
Mauritius is small: 1865 km2 (65 kilometers long and 45 kilometers wide) and 160 kilometers of coastline. It is located in the Indian Ocean, in the Southern Hemisphere, and belongs to the Mascarene Archipelago (with Reunion and Rodrigues). Madagascar, located in the west, is 855 kilometers from the island. The highest peak is the "Piton" of the Black River at 827 meters.
Project of Miss Delphine Legay :
I had decided to meet Ms. Legay in Mauritius since she started in ketology. Since June of this year, she has been planning a study entitled "Ceta-Squale Project: acting to save our oceans". In other words, on "Whales, dolphins and sharks of the Southwest Ocean Sanctuary; for a regional observatory of marine mammals".
Winner of the "Marcel-Bleustein Blanchet Foundation for Vocation" in 1997, Delphine was a student at the Sorbonne University in Paris and was preparing a PhD on the biology of cetacean behavior.
Of Mauritian mother, she decided to settle near the dolphins and whales of the Indian Ocean, little known in the world, despite a whale sanctuary. With her association "Ceta-Squale" of which she is the director, she has six main objectives on the island:
- To develop the research activity in marine biology by studying the large predators of the marine ecosystems such as whales, dolphins and sharks around the islands of Mauritius, Rodrigues, Saint-Brandon, Reunion, Madagascar, Mayotte, Comoros and Seychelles.
- Educate local communities about the need to protect marine life by training them, involving them in research, and talking to children.
- To train students in marine mammal and shark research so that the project can become a long-term study and last for many years with a local life.
- To protect marine biodiversity by proposing texts on how to act for the respect of ocean animals.

- Enhance tourism in the region by developing scientifically controlled whale ecotourism activities.
- The long-term objective is to ensure the conservation and ecotourism value of cetaceans by creating a marine mammal observatory on each of the islands.
His project is planned for two and a half years: from July 1999 to October 2001. Photo-identification has started on the "spinner dolphins" (Stenella longirostris), very numerous in Mauritius, and the "bottlenose dolphins" (Tursiops truncatus). The humpback whale (Megaptera novaeangliae) migrates along the island during the southern winter from June to October, its study will start next year, it will be accompanied by skin and blubber samples (biopsies).
The Indian Ocean includes about twenty species of cetaceans, but nothing is proven. Acoustics, ecotoxilogical studies, acoustic recordings and tagging will be studied. Miss Legay would like to know the interactions between cetaceans and sharks, in order to examine the bites inflicted on dolphins.
Experiences and swims:
Sperm whales (Physeter macrocephalus):
As usual, we got up at six o'clock in the morning to enjoy the calm sea and little wind. The fishing clubs located in the village had indicated the presence of sperm whales for years off the island. With our 4.50 meter Zodiac and a 25 horsepower engine, we headed out to sea. The sea was a sea of oil. We had taken the risk to leave despite our small boat. At about 4 miles (1 mile = 1853 meters), we met a group of about thirty "longbeaks" (Stenella longirostris). Smiling, Delphine told us that they might lead us to the sperm whales.
Surprise, a few minutes later, at 6 miles, we saw eight sperm whales in a tight formation, going south and facing the boat. Delphine decided to swim underwater to film them. I decided to accompany her. As soon as I started to swim, my heart was beating fast and I didn't breathe anymore. The sperm whales were moving slowly, separating, regrouping, and seeming to enjoy themselves. Only one decided to spy-hop, several times he observed our boat. The engine was cut, only the paddle was used. Delphine found herself in front of him, and he stood up. She had tears in her eyes. A few meters away from us, the sperm whales were caressing each other, sliding under each other for a few seconds; nature's magic. Without worrying about our presence, they were having fun. The "clicks" could be heard clearly under water. We then tried to catch up with them, but after a caudal stroke, we could hardly follow them. I didn't think anymore, I looked and my soul cried with happiness, then slowly the eight sperm whales sounded in the deep blue of the sea.
They came out further south, the sea being still as calm as ever. We wanted to see if the group included females, males or both. In front of us, the sperm whales went their way, without getting angry, compared to the small beings that we are. Delphine and I noticed that four females had just probed and shown their bellies, lined up and disappearing in the depths. My God, what an image! The recognition of a group including females was explained by the behavior of a male slipping under a female - or was it a game? Mystery. Under our feet, almost 1450 meters deep, enough to make us dizzy.
Bottlenose dolphin (Stenella longirostris):
Delphine Legay knew that our house was not far from a dolphin bay, "Tamarin Bay". The particularity of the bay allowed the dolphins to find a calm sea, shallow water and no lagoon, the waves crashing directly on the beach. For a very long time, fishermen had been seeing dolphins and sharks. Our study, from the beginning, allowed us to notice that a group often comes back, thanks to the recognition of a dolphin, whose dorsal fin is cut in two. We decided to name it "Captain Hook". A group of more than 100 individuals had already met our boat in the bay itself. The bottlenose dolphin (Tursiops truncatus) was seen with the common species of Mauritius. Also, offshore, we saw the pantropical spotted dolphin (Stenella attenuata) swimming with the long-beaked one.
After a series of photos of a group in the bay, we decided to get in the water our way. We stood on the surface of the water holding a rope firmly attached to the front of the Zodiac. The dolphins were surprised at first but slowly they came closer. With the speed reduced, the dolphins came to the bow a few feet from my face. I remember that two dolphins came from the right side at one meter from me, causing a great fear. Their whistles were very clear. A whole group, a few meters below the surface, was following the boat and its strange mount. Four hours in a row allowed us to get the best shots and enjoy their games.
Before heading back to France, I slipped into the water and stayed away from the boat. The dolphins were all around me but I could hardly see them. Suddenly, a group of them slipped underneath me, and followed me for almost fifteen seconds. A short but precious moment. Under my foot, about fifteen meters.
Conclusion:
With hindsight, the moments spent next to sperm whales or dolphins remained very strong. The first look of this mass in front of my eyes will be forever engraved in my memory. Alas, we were never able to see them again. But it was not a dream. The dolphins showed it to us.

I want to dedicate my stay to the Mauritians, for their kindness and respect, their magnificent island, to Delphine for sharing her unique moments with me, to the cetaceans, to the liquid element, in short, to nature par excellence.
December 1999
FRANCE
by Julien Marchal