River Sofia
Top ten facts about dolphins
There are currently 42 species of dolphins and seven species of porpoises.
Dolphins are marine mammals. They must surface to breathe air and give birth to live young.
A dolphin pregnancy last between nine and 16 months. The mother feeds her offspring on milk. The sons and daughters of resident orcas stay with their maternal family for life.
Dolphins eat fish, squid and crustaceans. They do not chew their food but may break it into smaller pieces before swallowing.
All dolphins have conical-shaped teeth. A Risso’s dolphin has 14 while a spinner dolphin can have 240.
The orca (killer whale) is the largest dolphin. Hector’s dolphin and Franciscana are two of the smallest.
The four river dolphin species inhabit the large waterways of Asia and South America.
Dolphins have an array of vocalisations such as clicks, whistles and squeals which they use for their well-developed communication and echolocation skills.
Lifespan varies from around 20 years in the smaller dolphin species to 80 years or more for larger dolphins such as orcas.
Maui’s dolphin is the most endangered dolphin. There are less than 50 individuals remaining. Fewer than 10 vaquitas (a species of porpoise) survive.
