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Today on Animal Fact Files we’re discussing dolphins. Technically all dolphins are whales, dolphins are toothed whales, like sperm whales and are separated from the other whale group, the baleen whales, like blue whales, because they don’t have baleen... or two blow holes but that’s beside the point!

Dolphins are typically separated from porpoises because dolphins tend to be leaner, have longer beaks, and rounded, hooked dorsal fins - if they have any dorsal fin at all that is as some dolphins don’t have dorsal fins. Dolphins are typically separated from animals with the common name “whale” because they’re smaller than animals commonly known as whales; however, some dolphins are more commonly known as whales, like the killer whale who just so happens to be the largest living dolphin species. These can reach more than 30 feet (9m) in length while the smallest dolphins max out at about four and a half feet (1.4m) in length.

There are just over 40 living dolphin species and most of them live in marine waters around the world. A handful of dolphins, however, are freshwater swimmers and live in rivers of southern Asia and South America. Unlike sharks and other fish who move their tails back and forth while swimming, dolphins and other marine mammals move their tails up and down. Like all living mammals, dolphins have hair - they just happen to lose theirs shortly after being born. Baby dolphins are usually born tail first after a gestation period of nine to seventeen months depending on the species. The baby’s fins are soft at birth, much like the spines of a hedgehog, and harden shortly after they’re born. Young dolphins nurse, or drink their mother’s milk, for upwards of three years and some may live in their mother’s group for the rest of their lives.

Dolphins tend to be social animals and live in groups called pods. These may number just a few individuals to thousands! The larger groups are typically found out at sea in deep water. Some dolphins, like bottlenose dolphins, can dive more than 1,500 feet (457m) in search of food. Dolphins are believed to have a bad sense of smell but can rely on echolocation, like some bat species, to find food.

Some dolphins have hundreds of sharp teeth that help catch and hold slippery meals like fish while others have far fewer teeth and just suck their squishy meals from the water, such as squids. These mammals are found in every ocean on earth, though most remain in warmer, tropical waters - one exception being the aforementioned orca who lives in arctic waters. River dolphins are some of the most threatened dolphin species because they have more limited habitats. In fact, there’s at least one river dolphin that has likely gone extinct during your lifetime. Since 2006, the whitefin dolphin is believed to be extinct. That year researchers spent weeks looking for them but were unable to find any living individuals.

Most dolphin threats are human in origin and include habitat loss as well as pollution (including noise pollution). Young dolphins may also be taken by sharks are other large predatory fish as well as other dolphins like killer whales. Smaller dolphin species tend to have short lifespans than large species with the lifespan of dolphins ranging from 20 to more than 60 years in the wild.

For more facts on dolphins, check out the links in the description. Thank you to Halima for today’s request! Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files!