Names and nick names can certainly be confusing there are eight dolphin names that feature the word ‘whale’, including pilo t whales, killer whales, false killer whales and melon-headed whales. However, classification is not an exact science and as more information and discoveries come to light, deliberations will continue and some dolphin species are likely to be further split into more than one species and/or subspecies. Fewer than 10 vaquitas (a species of porpoise) survive.Ĭurrently there are 49 dolphin and porpoise species which are grouped into six families: the oceanic dolphin family is by far the largest with 38 members the porpoise family has seven members and there are four river dolphin families, each containing just one species. There are less than 50 individuals remaining. Maui's dolphin is the most endangered dolphin.

Lifespan varies from around 20 years in the smaller dolphin species to 80 years or more for larger dolphins such as orcas.

Dolphins have an array of vocalisations such as clicks, whistles and squeals which they use for their well-developed communication and echolocation skills.

The four river dolphin species inhabit the large waterways of Asia and South America.

Hector's dolphin and Franciscana are two of the smallest.

The orca (killer whale) is the largest dolphin.

A Risso's dolphin has 14 while a spinner dolphin can have 240.

All dolphins have conical-shaped teeth.

They do not chew their food but may break it into smaller pieces before swallowing.

Dolphins eat fish, squid and crustaceans.

The sons and daughters of resident orcas stay with their maternal family for life.

A dolphin pregnancy last between nine and 16 months.

They must surface to breathe air and give birth to live young.

There are currently 42 species of dolphins and seven species of porpoises.

However, there's no evidence to substantiate this claim, Marino said, and no evidence that dolphins can heal people using echolocation.įollow Tanya Lewis on Twitter and Google+. For example, people have reported dolphins acting strangely in the presence of someone with a cancerous tumor. Some people claim dolphins also have the ability to diagnose or treat human ailments, but these claims are much less credible, Marino said. She suspects their echolocation must be learned as well.Įven though dolphins might be able to detect a pregnancy, giving birth near dolphins may be a bad idea, as the meat-eating marine mammals are known to sometimes be aggressive, scientists say. Baby dolphins, for instance, babble before they learn to make more complex sounds, Marino said. Dolphins use echolocation for many different purposes, from communicating in a group to disciplining their offspring, Marino said, adding, 'They're always buzzing!'ĭolphins probably aren't born with their echolocation ability, but develop it over time. Indeed, the animals have been seen buzzing on other pregnant dolphins. Just as sonograms give people a visual image of their babies, echolocation might give dolphins a mental image of them.īy extension, it's quite possible that dolphins can detect pregnancies in other dolphins, Marino said. 'We know from other studies that they are very good at going from a visual image to an acoustic image,' and vice versa, Marino said. Marino said she thinks dolphins probably see some sort of image of the baby. Still, the dolphins may not know that what they're seeing inside the pregnant woman is a person, he said. After all, water is the perfect medium for ultrasound, Walsh said.

'It would seem logical that they would have the potential to discriminate between different humans' who are pregnant or not, said Mike Walsh, an aquatic animal veterinarian at the University of Florida. But Nicolson, who wrote a book on the development of obstetric ultrasound, noted that this was only speculation.Īt least one study has found that dolphins can perceive shapes through an opaque barrier, such as a box. Dolphins might even have the ability to detect a fetal heartbeat in a woman they have never bumped up against before, he added. For instance, a dolphin that swims with a female trainer before and after she becomes pregnant 'might well be able to detect a difference in her echo profile,' or the pattern of sounds returned by echolocation, Nicolson said. Malcolm Nicolson, a history of medicine professor at the University of Glasgow in Scotland, agreed that dolphins may be able to detect a human woman's pregnancy.

Dolphin fetus