Bottlenose Dolphin

They are grey, varying from dark grey at the top near the dorsal fin to very light grey and almost white at the underside. This countershading makes them hard to see, both from above and below, when swimming. Adults range in length between 2 and 4 metres (6.6 and 13 ft), and in weight between 150 and 650 kilograms (330 and 1,400 lb).[20] Males are, on average, slightly longer and considerably heavier than females. In most parts of the world, the adult's length is about 2.5 m (8.2 ft), with weight ranges between 200 and 300 kilograms (440 and 660 lb).[3] Their size varies considerably with habitat. Except in the eastern Pacific, dolphins in warmer, shallower waters tend to be smaller than those in cooler, pelagic waters.[1] A survey in the Moray Firth in Scotland, the world's second northernmost dolphin population, recorded an average adult length of just under 4 m (13 ft) compared with a 2.5 m (8.2 ft) average in a population off the coast of Florida.
Bottlenose dolphins can live for more than 40 years.[21][22] However, one study of a population off Sarasota, Florida indicated an average lifespan of 20 years or less