Wednesday, April 4, 2007

About Atlantic Bottlenose Dolphin


I'm a member of Ocean Conservancy and just wanted to share info on bottlenose dolphins since that is what I was referring to...
Bottlenose Dolphins Scientific name: Tursiops truncatus
From the Ocean Conservancy Site



Dolphins were thought by ancient Greeks and Romans to bring mariners good luck, and appeared frequently in their legends. In fact, the Greeks honored them on more than 40 coins.
Thanks to their graceful beauty, intelligence, acrobatics and playful nature, bottlenose dolphins have fascinated people since ancient times. Streamlined and smooth, their bodies reach varying lengths from 6 to 12 feet, dependent upon geographic location. Females can live for more than 50 years, while males typically live for about 40 years.
Bottlenose dolphins produce several sounds, including whistles, clicksused for echolocation, and squawks. Their "signature whistles" areindividually distinct and are probably used to communicate the dolphin'sidentity, location, and emotional state.
Habitat & Diet
Found primarily in the temperate and tropical oceans of the world,bottlenose dolphins tend to be coastal dwellers, but they can adapt to avariety of marine and estuarine habitats.
They feed mostly on bottom-dwelling fish and squid. Adult males feedfarthest from shore, while adolescents and females with their calvestypically feed nearer the shore.
Social Organization
Social interaction is an important part of life for bottlenose dolphins,as it is for their cousins, the great whales. Dolphins typically formgroups of from two to 15 individuals. The structure of these socialgroups varies widely with regard to sex, age, familial relationships,and affiliation histories. Smaller groups tend to frequent near-shorewaters, whereas larger groups form in offshore waters.

Reproduction
After a gestation period of about one year, females give birth to livecalves, which they may nurse for up to two years. The interval betweenbirths is usually from three to six years.
Females reach sexual and physical maturity between five and 13 years ofage, long before their male counterparts. Males reach sexual maturity atbetween nine and 14 years, but they are not fully physically matureuntil their late teens. Most breeding males are at least 20 years old.

Threats to Bottlenose Dolphins
While fishing for dolphins still occurs in some parts of the world, suchas Peru, Sri Lanka, and Japan, most countries have outlawed thepractice. Nonetheless, dolphins are stilled killed incidentally in otherfisheries-including tuna, sardines, and anchovetas.
Some bottlenose dolphin populations have declined as a result ofpollution and habitat alteration. Dolphins are known to accumulatecontaminants in their tissues, which may affect dolphins' ability toreproduce and contribute to higher infant mortality. Because manydolphin populations frequent near-shore areas, they are particularlyvulnerable to entanglement in fishing gear and boat collisions.