The bottlenose dolphin (Tursiops truncatus) is probably the most well-known dolphin species in the world. There appears to be a general trend of inshore specimens being smaller than the larger, more robust variety that live offshore; but in British waters, we’re known for having some of the longest and stockiest specimens in the world, throughout our coastal waters. They have a torpedo-shaped body, are coloured dark grey along the back, paler grey on the flanks and more white-pinkish underneath, and earn their common name with their long, protruding rostrum.
The most easily-recognisable features of the bottlenose dolphin as it breaks the surface of the water are its tendency to display acrobatic feats as it leaps from the water, but more so the more curved, sickle-shaped dorsal fin and overall body size, relative to the other most commonly-sighted cetacean in this region, – the harbour porpoise (Phocoena phocoena); which is much smaller, and has a more triangular dorsal fin.
Adult males usually range between 2.4 – 3.8 meters in length. Female adults tend to be slightly smaller, typically anywhere from 2.3 – 3.7 meters.
IUCN status Least Concern
Common as they are, along almost all of the world’s temperate, tropical and subtropical coasts, we find them in high abundance in this region, too. The International Union for the Conservation of Nature (IUCN)’s Red List has classifies the Common Bottlenose Dolphin as Least Concern (LC), and are listed under Appendix II of CITIES. Protection, or at the very least, study of this species, is still vital due to the role it plays as an apex predator in each of the ecosystems that it occupies. The affects of human disturbance, hunting and being caught in fishing nets need to be continually monitored to ensure that our populations do not start to suffer at an increased rate.
Where to find them:
Bottlenose dolphins occupy both coasts and offshore habitats, often found in both open waters, and also rocky reefs and lagoons. The species are regularly seen throughout the region, occupying the entirety of Liverpool Bay (from the Dee estuary all the way as far north as the Cumbrian coast); with the mouths of the Mersey and Dee rivers, and off the coast of Blackpool being the main areas where they’re spotted by the public, in recent years.
Famous for its intelligence and cognitive ability, the Common Bottlenose Dolphin engages in a wide array of feeding and hunting behaviours, many of which are unique to specific populations in isolated areas. The range of prey species that they hunt is just as wide, including numerous species of small fish, crustacean and squid.
Did you know the bottlenose dolphin engages in an interesting, but as yet largely under-studied interaction with the region’s other, most abundant cetacean, the harbour porpoise. The dolphins have been known to harass them, rake them with their teeth; potentially resulting in the death of the porpoise. Numerous such injured porpoise have been washed up on our coasts, dead. We don’t yet know the reasons for this behaviour.
Did you know that Liverpool Bay Marine Life Trust aided in the first photo identification bottlenose dolphin off Merseyside.