Marine wildlife

Marine Biodiversity

Nosy Be marine areas offer magnificent natural aquariums where you can find many varieties of fish, corals, shellfish and other aquatic species.

Among all these species, we can observe among others:

  • Whale shark
  • Humpback whale
  • Humpback dolphin
  • Tusiops, the Indo-Pacific bottlenose dolphin
  • Stenella longirostris, Stenella attenuata, Long-beaked dolphin
  • Leopard shark
  • Manta ray, stingray, eagle
  • Green turtle, hawksbill turtle
  • False killer whale
  • Globicephala macrorhynchu
  • Barracuda, lutjan, snapper
  • Parrotfish, grouper, platax
  • Moray eel



Nosy Komba shelters a varied and abundant marine fauna.

Sea turtles are present all year round and it is common to see a turtle poking its head out of the water to catch its breath, either from a boat or from the beach.

Several families of humpback dolphins live all around the island. Several families of humpback dolphins live all around the island. Sometimes you can see them playing and jumping between the villages of Anjiabe and Antamontamo.

Humpback whales

What season to watch whales in Nosy Be?

Humpback whales stay in Nosy Be from July to November. This is only a stage in their migratory cycle, because each year, humpback whales travel about five thousand kilometres from their feeding grounds in the deep south. They travel to warmer, shallow, well-protected waters. Some come to breed, and some come to give birth.

They feed on plankton and their young, while protecting themselves from marine predators that prefer cold water.
In Nosy Komba, excursionists propose sea trips to observe them. They are usually found offshore, but they can sometimes be seen from the shore.


They are easily recognizable. They have a robust body, black back and flanks, and white belly. The dorsal fin has a hump at its base and the caudal peduncle is quite short. The whale’s head has many protuberances and tubercles cover the lower jaw. It has long black and white pectoral fins (about 1/3 of the body, the largest in the whale family) with a serrated edge.
Its adult size is about fifteen meters, some females can measure up to 19m. These whales weigh between 30 and 40 tons as adults and 1 ton (for about 4 meters) for the calf at birth. The life expectancy of a humpback whale is about 50 years. Just like our fingerprint, each whale has a black and white mark on the inside of its tail that characterizes it.

Reproduction and behaviour

Females are very protective of their calves. They caress them with their pectoral fins and act as a shield in case of danger. As for the calf, it always stays very close to its mother. Nursing lasts about a year. Among the whales, humpback whales are the most gifted in jumping.
They sometimes perform acrobatics that allow us to admire for a few seconds their large pectoral fins and their splendid black and white tail. They fall back into the water on their backs.

When this majestic cetacean surface, it expels the air in its lungs, and its breath causes a cloud of nearly three meters.

Humpback whales communicate in part through a very elaborate song, composed of phrases repeated like the progressions of a musical score. The song can be heard underwater for dozens of kilometres.


The life of this majestic animal is very fragile. In addition to predators such as killer whales, sharks and disease, man remains their greatest danger. Whaling, but also the repercussions of human activity: pollution, boats, drift nets… are all factors that make their lives more fragile.

Whale sharks

When to watch whale sharks in Madagascar?

The whale shark frequents the waters of Nosy Be from September to December. It is possible to see them the rest of the year during a cruise or a scuba dive, but this period is the best time to see them.

For a respectful observation of whale sharks, it is advisable to respect certain rules:

    • Boats must respect an approach distance of 15 meters.
    • Swimmers must stay between 3 and 4 meters from the fish.
    • It is recommended to be vigilant, even with this distance.
    • It is forbidden to touch them.
    • Avoid violent flipping and sudden movements.
    • Sunscreens are toxic for them.


Unlike the whale, which is a mammal, the whale shark is a fish. It is the largest fish in the world: its average size is eight metres, but some measure more than ten metres. Its weight varies up to twelve tons. This massiveness may impress, but these creatures are gentle and harmless to humans.
Their thick dorsal skin covered with ridges and dots makes it easy to distinguish them. These dots on their backs allow for individual identification. The whale shark feeds mainly on krill, small fish and squid, as well as plankton, which it filters, and a liquid that corals spread.
Although it travels thousands of kilometres on its migrations, it moves rather quietly.


During their breeding season, it is possible to observe groups of whale sharks, although this one is quite solitary.
How gestation occurs is still a mystery to this day. Like many sharks, whale sharks are born fully formed and measure about forty centimetres in length at birth.


As with the whale, the threat to these large fish from human activity is growing. Overfishing and ocean pollution are a major threat, and whale sharks are now considered a vulnerable species.

Discover the local culture

Nosy Komba is very attached to its traditions and ancestral rituals…

On the same subject…

The birds

The birds

There are more than twenty species of birds on the island of Nosy Komba.

Maki Macaco

Maki Macaco

Many lemurs macaco are living in Nosy Komba. There are several mixed groups led by females.


Questions / Advice

Can we swim with the humpback whales in Nosy Be?

No, the rules prohibit the launching of swimmers with whales in Nosy Be and everywhere in Madagascar.

What is the approach distance for a whale watching boat?
The observation zone for humpback whales is defined in the Madagascar marine mammal approach official document. It is located between 100m and 200m.
How to spot humpback whales from far away?
Humpback whales can be spotted by their vertical blast that releases a spray of water, which rises more than two metres from the surface of the water and can be seen for miles. They can also be spotted when they jump out of the water.
When can I see whale sharks?
Whale sharks are present in Nosy Be area from September to December.
Can we swim with whale sharks in Nosy Be and Nosy Komba?

Yes, some excursionists offer to swim with whale sharks. These animals are vulnerable and fragile, and a distance of several meters from the animal must be respected.