Follow by Email

Tuesday, April 8, 2008

bottlenose dolphins

The bottlenose dolphin is recognizable by its large curved dorsal fin and gray body with muted color patterns. Males sometimes exceed 12 feet and 1,200 pounds, living 40-45 years in the wild. Females are smaller and longer lived. Widely distributed, the dolphin inhabits tropical and temperate latitudes around the world, residing both offshore and in estuaries, bays and the lower reaches of rivers. A playful animal, bottlenoses are often spotted bow-riding, wake-riding and body-surfing across the surface.
Inshore bottlenose dolphins differ markedly from the offshore variety, which tend to be darker with larger bodies and smaller flippers. They also typically gather in larger social groups, sometimes numbering more than a hundred, than inshore dolphins. Bay residents gather in groups as small as 2-15. Both varieties prey on fish, inshore individuals supplementing their diet with marine invertebrates. Often they are attracted to commercial fishing operations, feeding off discards or escapees. Their more unusual hunting practices include chasing fish out of the water and then partially beaching themselves to feed.
Though worldwide populations remain vibrant and widely-distributed, some regional populations are endangered by hunting, degradation of habitat and conflicts with commercial fishing. The Black Sea population is in particularly narrow straits, decimated by severely degraded water quality and killings that continued well into the 1980s and 1990s. Pollution, gill net entanglement and the collapse of fish populations threaten Mediterranean populations.