Diving and Marine Biology in Nosy Be, Madagascar.
Marine biology diving can have several applications:
- Learn to avoid the dangers of the environment (hydroids, some shells, some equinoderms, some corals, and other poisonous animals)
- Learn to search for animals to observe. Many animals are confined to a specific biotope. Depth, environment (corals, algae, sandy bottom, sponges), and current conditions... all this will be decisive in defining the type of animal you can meet. Especially for small animals, such as seahorses, nudibranchs, frogfish, ghost fish...
- referencing animals. We list nudibranchs and flatworms for several international scientists because the evolution of knowledge of these animals is very fast, and there have been very few studies carried out on the reefs of Madagascar.
- Monitoring of "Bleaching alerts" (alerts of coral bleaching due to too high water temperature: March-April) issued by CORDIO (scientific institute monitoring the evolution of coral reefs in the Indian Ocean) and estimation of percentages of corals temporarily affected or dead.
- Learning to behave responsibly. So that the reefs remain healthy, Do not try to touch the animals (stroking a shark or a turtle generally leads to its death, by parasitization giving tissue necrosis), control its buoyancy to avoid the contact of fins with the corals or bury them, respect the crustacean fishing closures (lobster, crab, shrimp: do not buy, do not order..) to allow them to reproduce.
- Learn to see the richness and diversity of the reef. Diving to see the big stuff is good.. when it is present, and when he decides to come and see us. All the rest of the time, there are plenty of little individuals competing in color, shapes, and who are always present, observable every day.
Diving and Geological Context of Nosy Be
Due to its particular positioning, between Madagascar and Africa, the geology of Nosy Be is varied. Influence of Madagascar, torn by the bursting of Gondwana and the opening of the Mozambique Channel, Modeled by several volcanic episodes from ancient to Quaternary, the island presents sedimentary entities (shists and liasic sandstones) all interspersed by more or less eroded plutonic intrusions.
Sea level varied a lot. During the various glaciations which punctuated the Tertiary and the Quaternary, the sea level could be up to 42m lower, which explains certain faults, caves in the reef. Likewise, the "fossil beaches": We have 3 diving sites which show "fossil beaches": at 25 / 27m, sites including the topography (Extension of cape, slight sandy slope, large blocks of granite polished by the assault swell) show a beach edge during a last ice age, when the sea level was lower. These granite blocks are now covered with a specific fauna, including large clumps of black coral.