Common Bottlenose Dolphin - Tursiops truncatus Media:commonbottlenosedolphin.jpg
Habitat Bottlenose dolphins live in warm, shallow waters close to the shore. They are also commonly seen in bays and lagoons, and large rivers.
Range Generally the common bottlenose dolphin ranges in temperate and tropical waters of the Atlantic and Pacific Ocean and also connecting seas. In the United States these dolphins can be found year round in Florida and Hawaii and during the summer from Cape Hatteras, NC to Point Conception, CA.
Description The appearance of the bottlenose dolphin can range from light gray to black. Those that live inshore are smaller and lighter in coloration and those that live offshore are larger and darker in coloration. These animals are 6-12.5 feet long and can weight 300-1400 pounds.
Lifespan The bottlenose dolphin can life between 40-50 years. Males live between 40-45 years and females live over 50 years.
Diet and Feeding Style Normally these dolphins are found in groups of 2-15 when inshore, but when off shore they can be found in groups of hundreds. To locate and capture prey, such as small fish, squid, and shrimp, they use high frequency echolocation. They have several different feeding styles; hunting in groups, chasing fish into mudflats, and striking the fish with their flukes to knock it out of the water.
Life History Sexual maturity varies between populations but usually falls between the age of 5-14 years. Off the coast of Florida, the mating time is between March and April. The gestation period lasts for 12 months meaning that the calves are then born between February and May. Lactation lasts for 12-18 months, but the calf can feed on solid food after 6 months. The calf will stay with the mother for 4 or 5 years. There is normally a 2-3 year time interval between pregnancies. Female bottlenose dolphins reach sexual maturity between 5-12 years of age, while males reach sexual maturity between 9-13 years of age.
Threats and Conservation The bottlenose dolphon faces many threats to its populations including; injury and mortality from gillnets, seines, trawls, and longlines used when fishing, viral outbreaks, harvest hunting in select countries, and exposure to biotoxins and pollutants.
In the United States there have been modifications done to the fishing nets used in order to protect the dolphins from getting caught in them. Also it is illegal to take or kill dolphins in United States waters; the dolphins are protected under the Marine Mammal Protection Act of 1972.
Journal Articles To learn more about the common bottlenose dolphin here are some articles with more information:
Juan Pablo Torres-Flórez, et al. "Southernmost Distribution Of Common Bottlenose Dolphins (Tursiops Truncatus) In The Eastern South Pacific." Aquatic Mammals 36.3 (2010): 288-293.
This journal discusses the possibility of new colonizations of the bottlenose dolphin in the Southern Pacific which indicates the furthering its range southward.
Randall S. Wells, et al. "Prey Selection By Resident Common Bottlenose Dolphins ( Tursiops Truncatus) In Sarasota Bay, Florida." Marine Biology 157.5 (2010): 931-942.
This journal discusses a study done in Sarasota Bay, Florida on the prey selection of the bottlenose dolphin, by looking into availability, abundance, and hunting techniques.