Common Name: Indo-pacific bottlenose dolphin
Tursiops spp: The Tursiops genus has been split into two, T. truncatus and T. aduncus. The taxonomy of this genus is still not thoroughly clear, however due to considerable geographic variations, additional species may be recognised in the future.
General Description: Indo-Pacific bottlenose dolphins have a large, robust head and trunk, a gently curving melon with a sharp crease before the beak. The beak is moderately long and slender compared to the common bottlenose dolphin. The dorsal fin is tall and triangular (not as falcate as common bottlenose dolphins) and larger than in common bottlenose dolphins. The flippers are long and pointy at tips.
The colouration is variable, but usually shades of light grey on the flanks, grading to white or pink on the belly. Belly is marked with speckles or black spots in adults. Usually a dark ring is present around the eye.
Size: Calves: Length of animals at birth is approximately 85cm – 112cm. Adults: Adult dolphins are between 2.7 m, males tend to be slightly larger than the females. Maximum weight is around 230kg.
Appearance At Sea: While Tursiops is easy to identify at sea given the relatively short beak, robust body, convex melon, sharp beak crease and body colour pattern, it is not easy to separate between T. trunctus and T. aduncus. A suite of characteristics need to be checked, and good pictures is the best way to confirm.
Found In: Occur on the continental shelf in shallow coastal and around oceanic island groups.
Records from India: From offshore waters of peninsular India and the Lakshadweep and Andaman Nicobar Islands.
Could Be Confused With: In areas where they overlap in distribution, they can be confused with common bottlenose dolphins, rough toothed dolphins and spotted dolphins.
Diagnostic Features at sea:Can be distinguished from common bottlenose dolphins based on overall size, shape of body, shape of head and beak, spots on the belly, shape of dorsal fin and colouration.
Stranded specimens: Stranded individuals can best be identified based on total length, shape of fin, length of beak and teeth count between 21-29 pairs in each jaw.
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