Dolphins of Comoros
False Killer Whales (Pseudorca crassidens)
Distribution of false killer whales, Comoros
False Killer whales family, Chindini 2019
Spy hopping False Killer whale, Chindini 2019
False Killer whales family, Chindini 2018
This species of dolphin was observed for the first time by Moidjio CRCAD in October 2009 during a crossing between Moheli and Chindini and it was the first documented observation of this species in the Comoros. Since Moidjio CRCAD observes this species regularly south of Grande Comores between Chinidini and Mohéli. We think it is a resident species of Grande Comore. Locally, we call him Mafoumba and he is a dolphin who is not shy, he comes to feed on fishing lines and come into contact with humans. It is a large dolphin that can reach up to 6 meters long, it has the shape of a torpedo, a long, slender and streamlined body, a round snout, without beaks and a slightly distinct melon of the body. It is completely black with a slightly paler coloring below, its melon is also sometimes darker. A white heart shape is between its two pectoral fins. Its dorsal fin is located in the middle of the body, rather small compared to its body, rounded at its end and slightly curved. Older males have dorsal fins that hook and are distinctively more curved. The pectoral fins are small and pointed and curved, forming an impression of articulation at the elbow. It is a very social animal that lives and hunts with the family. They feed on fish of different sizes and are not afraid to tackle big tunas. They share the food by passing the pieces of flesh through their mouths and cutting pieces in the process. This behavior was observed several times during our expeditions. The groups encountered vary between one individual and up to twenty animals. They have been observed alone or in the company of dolphins on multiple occasions and Fraser dolphins on two occasions. In other parts of the world it is known to feed on other cetaceans but this behavior has not been observed in the Comoros until now. Finally the Mafoumba is a dolphin that produces a strong smell of fish, typical, detectable at great distance. He is very vocally active and his whistles are very typical, they click and whistle at the same time.
Melon headed whales (Peponocephala electra)
Distribution of Melon headed whales, Comoros
This dolphin is of average size between 2.2m and 2.7m, it lives in very big group counting between 200 and 500 individuals divided in small groups from 5 to 20 individuals sailing in tight formation. It is a fairly regular sighting around the Comoros Islands and especially in the southwestern Chindini area in deep waters and also near the coastline. It is an animal very little observed in other parts of the world. It is an animal that is very similar to the false killer whale, its wing is smaller, less robust, its muzzle is without beak and more pointed than the false killer whale, its body is more tapered, its pectoral fins are thinner and pointed. It is black, brownish, with a more marked coloration, greyish at the level of the melon. He has white lips, less pronounced than the Pygmy killer whale.
The most tangible criterion for its identification is the number of individuals in a group, from 2 to 30 they are probably Pygmy killer whales, large groups larger than 100, they are the dolphins of electra. Literature describes him as a fierce animal and who does not let himself approached, our observations shows that he is on the contrary very calm and allows himself to be approached, he is even curious and come to our contact. He is very vocal and his acoustics are very complex. On two occasions, we observed the Electra dolphin accompanying female humpback whales that seemed to give birth. Is it altruism or interest, we do not know. Our theory is that either they expect the newly born calf to eat it, or they wait for the large placenta to feed on it.
Pygmy killer whales (Feresa attenuata)
The Pygmy Orca is a medium-sized species of dolphin, less than 3m. It is quite rare to observe it in the world and also in the region, little is known about this elusive species. It is a black dolphin, slate, much like the false killer whale, a dark band extends from the melon to the dorsal where it widens to become a saddle. The pygmy killer whale, with a rounded snout, without beak, white lips more or less extended, his body can be strewn with scars. It has a robust body which is lengthened, refined towards the base of the peduncle. The dorsal fin is tall and broad for its size, of various shapes, its pectoral fins are relatively long and rounded at the ends. Moidjio CRCAD observed this species on three occasions: a group of 20-25 individuals between Chindini and Moheli, a group of 3 and 6 individuals west of Chindini near the submarine canyons. It is a dolphin known for its aggressiveness in captivity, very shy when approaching the boats and always in active swimming. Our observations show the opposite, each observation was long and we could approach them several times to take their photo-ID and swim with them without feeling aggression. Their swimming was slow and on two occasions they floated on the surface without moving.
Distribution of Pygmy killer whales, Comoros
Risso's Dolphin (Grampus griseus)
It is a medium-sized dolphin reaching 3.5m, frequenting deep waters and abyssal fauna. It is very easy to identify by its greyish coloring with white scars, the extent of these scars is such that some individuals, usually older, appear virtually white. It has a robust body, its dorsal fin is very tall, thin and arched, it has a large melon, devoid of bill, slightly pointed at the level of the mouth. Its melon is split from a channel, centrally from the muzzle to the vent.
Moidjio CRCAD has observed this species on four occasions, mainly along the abyssal cliff that separates Grande Comore and Mohéli in groups of 10 to 60 individuals. It is a very shy and elusive species that can not be approached. It is a specialist in deep water and can stay 30minutes in apnea.
Distribution of Risso's Dolphins, Comoros
Bottlenose dolphin - Indo-pasific bottlenose dolphin
(Tursiops truncatus-Tursiops aduncus)
There are two subspecies of bottlenose dolphins living in Comoros, the Common Bottlenose Dolphin and Indo-Pacific Bottlenose Dolphin. Both forms of dolphins are similar and difficult to observe at sea. The common dolphin is larger between 3 and 4m long and 2.5m for the indo-Pacific. The GDC has a shorter and more robust bill, a larger and more robust dorsal fin, a more defined and more bulbous melon. The GDC also looks darker. The GDIP him, sometimes presents spots of black pigments on the belly. Generally speaking, the bottlenose dolphins are gray in color, dark gray with a slightly darker cloak.
The GDIP seems less fierce than its cousin the GDC. Moidjio CRCAD observed both species, GDC was either in a group alone or in association with pilot whales in groups of 3 to 20 individuals, GDIP was observed either as a group alone or in the presence of False orcas, Peponocephali or dolphins. Fraser. It is a dolphin that occupies all layers of depths and we can find it offshore and ready odds.
Distribution of Bottlenose dolphins, Comoros
2 different species or subspecıes of bottlenose dolphins in the water of Comoros not yet clearly identifıed... to be continued.
Pantropical spotted dolphin (Stenella attenuata sp.)
It is a medium-sized dolphin reaching 2.6m, it is a fairly common sight in the Comoros. It is an animal that prefers deep waters. In our observation area it seems to prefer the southwestern part of the Chindini region, the so-called dolphin bay. It is found in large groups of 3 to 400 individuals when in single-group, may be associated with tuna or other marine mammal species such as spinner dolphin and electra dolphin but smaller groups of 20 to 40. It is recognisable at a distance by the shape of its dorsal fin, small, fine and curved. It has a large dark cape, concave at the level of the dorsal which goes down quite low on the flanks.
The flanks are bluish-gray, he wears a dark mask around his eyes, his beak is medium in size, dark with a white tip and fine white lips. His body is more or less dotted with small light spots on the dark and dark parts on the light parts. Younger individuals have virtually no spots. It is also an acrobatic dolphin who can undertake spectacular jumps reaching heights of 4 to 5m. He is less player than the long-nosed dolphin, but tends to play with the boat if he is not busy hunting.
Distribution of false Pantropical spotted dolphins, Comoros
Spinner dolphin (Stenella longirostris sp.)
It is a small dolphin that does not exceed 2m. It is the most southerly species of Great Comoros with a resident population that seems to appreciate the proximity of the Mahle coral reef. It is found everywhere in the Comoros near shallow areas. It is known to hunt at night in deep water and rest and socialize near the coast. It is an easily recognizable animal with a very long tapered beak, a tri-partite coloration (a black cape, gray sides and a white belly), a black mask from the beak to the armpit through the eye Some individuals of Long-billed Dolphins in the Comoros appear to have the distinctive feature of having yellowish flanks, which do not appear to have been noted in other areas, it also appears that some groups have smaller individuals than other groups and some individuals have pink belly (juveniles). It is possible that 2 subspecies coexist in the Comoros. Its dorsal fin is quite small and triangular. It is a very acrobatic dolphin who performs multiple tendrils during his jumps. He is a player and always comes into contact with the boats and he races with them. The group we follow counts in the 300 individuals who appear to be a cohesive group per occasion and splits into smaller groups on other occasions.
Distribution of Spinner dolphins, Comoros
Fraser's dolphin (Lagenodelphis hosei)
Distribution of Fraser's dolphins, Comoros
It is a medium sized dolphin between 2.5m and 2.8m, robust and very active surface, it forms groups of 200-300 individuals. Its dorsal fin is very small compared to its body and triangular. General appearance, It is gray / light blue, with a long dark band lined with thin light bands, from the beak to the peduncle. For the males this band is practically black and for the juveniles, very little distinct from the rest of the body. Its beak is very short and wide enough. Moidjio CRCAD has met dolphins on 3 occasions, once in a single group, a faith in the presence of false killer whales and a last opportunity in the presence of false killer whale and bottlenose dolphins. He is a dolphin who does not let himself be approached and does not like the company of the boats, he swims very fast and in tight formation. It is an offshore dolphin and its presence around the Comoros Islands is rare.
Short-fin Pilot whale (Globicephala macrorhynchus)
The tropical whale is a species we do not meet often, we have only seen it once in the southwest region of Chindini. It is a deep water animal and prefers life offshore. It is easily recognizable with its round, very sturdy dorsal fin, a very wide base and located very in front of the animal. His head is very round, wide in the shape of a bulb. Their pectoral fins are long, thin and pointed. The males are larger, larger, more massive and their dorsal wider. It is a large dolphin that reaches 7m long, its body is profiled, end with a very arched peduncle. They are very dark, black in color, they have a white shield in the shape of a heart on the chest, the juveniles are pale, in light gray. It is a very social species that lives in groups of 20 to 100 individuals, preferring deep offshore waters, it feeds almost exclusively squid. Moidjio CRCAD makes its first observation in 2018 of a group of about thirty individuals and two dead individuals, stranded in the mangroves of Nioumachoua in Mohéli.
Distribution of Pilot whales, Comoros