In U.S. waters of the western North Atlantic, the bottlenose population is estimated at about 11,700. Of course, at least 9,200 are offshore animals. The Mediteranean population is estimated at less than 10,000. 2. Bottlenose dolphins are not endangered. Chromosome banding techniques have proven useful in bottlenose dolphin population studies.
Scientists can identify individuals and determine relationships among dolphins in a group.
Bottlenose dolphins measured off Sarasota, Florida averaged 2.5 to 2.7 m and weighed between 190 and 260 kg. Differences in body size and skull dimensions may be related to habitat differences. The two northwestern Atlantic ecotypes exhibit a pronounced size variance. Large bottlenose dolphines in the Pacific may be 3.7 m and weight kg. In the Mediterranean, bottlenose grow to 3.7 and more.