Learn all about the endearing bottlenose dolphin, which lives and plays in the waters off the British coastline

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Published: Thursday, 04 July 2024 at 15:39 PM


Celebrity comes naturally to some. The cry of ‘dolphin!’ stops most people in their tracks, necks craned and eyes shielded from sunlight reflected on the waters where this most talkative of acrobats plays.

 Our entire coast is a part-time theatre for bottlenose dolphins: from Cornwall to Orkney, Brighton to Northumberland, they spin magic.

Dolphins are good for us – they boost our economy via wildlife watching tours, and bring a smile to many faces. But they also challenge us to tread a little more softly on the marine environment.

What are bottlenose dolphins?

Bottlenose dolphins are marine mammals. There are two species of bottlenose dolphin: the common bottlenose dolphin (Tursiops truncatus) which we see in our seas and the Indo-Pacific bottlenose dolphin (Tursiops aduncus).

How do bottlenose dolphins communicate?

Bottlenose dolphins need quiet so that they can talk. Their whistles pulse around them as they speed through the water; each dolphin has a unique call, and some research suggests they mimic the whistles of others to address them by ‘name’. 

How many bottlenose dolphins live in a pod?

Large-brained, gregarious – pods can reach 1,000 individuals, although groups of 15 are more common.

How long do bottlenose dolphins live?

Bottlenose lifespan can live for several decades, and usually notch up between  30 and 50 years in the wild

How smart are bottlenose dolphins?

The bottlenose dolphin is famously one of the smartest and most self-aware of all wild species. They are one of a select few which recognises itself in a mirror. One population in Australia even exploits tools, using marine sponges to aid their foraging for prey on the sea floor.

How big are bottlenose dolphins?

Our British bottlenose dolphins are some of the largest of this highly international species, tipping the scales at up to 365kg. 

What do bottlenose dolphins eat?

What a bottlenose dolphin eats will depend on where it lives. For those in the Moray Firth, there’s nothing better than a plump tasty salmon. For others it’s squid and crustaceans. They swallow their food whole and if you watch a dolphin hunting fish, you will often see it tossing its prey into the air to get a better angle so that it slides down the throat more easily. They hunt using echolocation.

How to tell the difference between bottlenose dolphins and harbour porpoises?

Their size, sociability and greyness distinguish them from the chubby dark frame of the more solitary harbour porpoise, which is the other cetacean likely to be seen close to shore. It is fair to say that porpoises have little reason to share our affection for dolphins, which can attack them with extraordinary aggression. But then to a dolphin, a porpoise is an intolerable competitor for cod, pollock and other marine delicacies.

What threats do these dolphins face?

It is the fish taken by people that lure dolphins into greater trouble. To avoid killing marine mammals as bycatch, fishing boats may be fitted with acoustic ‘pingers’, but it is feared that some dolphins deliberately approach this noise because they have learned it means a netted fish shoal.

At other moments, it is not our diets but our curiosity which can harm dolphins – if you are lucky enough to find a boat while boating, please keep a respectful distance and enjoy them with a clear conscience. Natural celebrities perhaps, but they are legally entitled to protection from disturbance.