What are bottlenose dolphins?
Bottlenose dolphins are marine mammals. There are two species of bottlenose dolphin: the common bottlenose dolphin (Tursiops truncatus) and the Indo-Pacific bottlenose dolphin (Tursiops aduncus).
Where do bottlenose dolphins live?
Bottlenose dolphins are found in warm and temperate seas worldwide, except in the Arctic and Antarctic Circle regions.
How big are bottlenose dolphins?
Bottlenose dolphins are around 4m in length. They weigh on average 300kg, but weight can vary between 150 and 650kg depending on where they live. Those in Scotland's Moray Firth are thought to be the biggest.
What do bottlenose dolphins look like?
Bottlenose dolphins are varying shades of grey all over, with a distinctive bottle-shaped rostrum (snout)
Do individual bottlenose dolphins have particular markings?
Yes. Individuals are recognised by distinctive and unique markings on their dorsal fins.
How many teeth do bottlenose dolphins have?
Teeth are more numerous in T. aduncus than in T. truncatus (T. aduncus has 23–29 teeth in each row; T. truncatus 19–27 teeth per row). Teeth are used for catching and gripping prey.
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.
Do bottlenose dolphins use teamwork when feeding?
Yes. They either feed alone or in groups where they work together to catch prey. Strand-feeding is a technique used by bottlenose dolphins near and around coastal regions of Georgia and South Carolina, where they encircle a school of fish in a mini whirlpool and then force them to the shore and scoop them up. They also use mud-ring feeding, where they entrap the fish within a mini-mud whirlpool, confusing their quarry and allowing them to be caught.
Bottlenose dolphins are also known to cooperate with humans. In Brazil, fishermen and bottlenose dolphins work collaboratively to catch fish.
How did the bottlenose dolphin get its name?
The Latin name derives from the Latin tursio (which means dolphin) and the Greek ‘ops’ which means ‘appearance’, followed by truncatus for the characteristic truncated teeth. Aduncus is from the Latin for ‘hooked’, possibly referring to the slightly hooked lower jaw. The common name derives from the distinctive bottle-shaped rostrum.
Do bottlenose dolphins form superpods?
Bottlenose dolphins are typically found in pods of 2–15 individuals, though pods of more than 1,000 have been reported, otherwise known as a superpod. Living in groups is an effective form of defence.
Do bottlenose dolphins stampede?
A stampede is when hundreds, sometimes thousands of dolphins are seen leaping in and out of the water (known as porpoising) at top speeds (as there is less resistance through air than through water). They are heading in one direction, as if moving towards or away from something.
No one knows for sure why dolphins suddenly begin to stampede, but they could have been alerted to a food source, be evading a nearby predator or meeting up with another pod of dolphins. Bottlenose dolphins are rarely seen stampeding.
How do bottlenose dolphins breathe?
Dolphins are voluntary breathers, meaning they have to deliberately come up to the surface to breathe. They can stay underwater for around 20 minutes. Bottlenose dolphins are very active on the surface, breaching and tail slapping, which is part of their sociality. Sometimes they may just want to check out what’s going on above the water.
How long do bottlenose dolphins live for?
A bottlenose dolphin's lifespan is usually between 40 – 50 years.
How high can a bottlenose dolphin jump?
Bottlenose dolphins can jump around one body length in height.
How deep can a bottlenose dolphin dive?
It would depend on usual habitat but approximately 200m (some have been recorded deeper).
How fast can a bottlenose dolphin swim?
Around 20kph
How intelligent are bottlenose dolphins?
They are smart. Like us, they like to play just for the fun of it and that is a sign of intelligence.
They also use tools. A group of common bottlenose dolphins in Shark Bay, Australia, hold sponges to stop their beaks getting scratched and cut when they search for food on the rocky seabed. This unique hunting technique was started by a single female dolphin, who taught her daughter how to do it and eventually spread the useful custom to the whole group. This is an example of culture - new behaviour that is invented and passed on through learning – something we know is also important to chimpanzees and humans.
Bottlenose dolphins have special brain cells called spindle neurons. Humans and great apes have them too, and scientists think they enable us to feel complicated emotions and also to understand and relate to how others are feeling (empathy). Studies have led some researchers to suggest that bottlenose dolphins may experience emotions on a level far greater than humans and have much deeper and more complex social bonds than we do.
What is the social organisation of a bottlenose dolphin?
Fission-fusion – meaning a fluid dynamic. Some individuals stay together over longer periods of time and make long-term relationships, others move between groups.
How do bottlenose dolphins breastfeed underwater?
They breastfeed in the same way as other whales and dolphins. The calf inserts its tongue into the mammary slit of the mother and sucks.
How long will a calf stay with its mother?
Usually around 3–5 years but can be as short as 18–20 months.
What sounds do bottlenose dolphins make?
Bottlenose dolphins produce three primary categories of sound: whistles (individual identity), echolocation clicks (foraging and navigation), and burst-pulse sounds (social behaviour).
Does the bottlenose dolphin have any natural predators?
It depends on where they live but in many habitats, sharks are the main predator.
What threats do bottlenose dolphins face?
All bottlenose dolphins face daily threats from noise and chemical pollution to hunting and death in nets. Nets, particularly gill nets, are the biggest single killer of whales and dolphins around the globe. Plastic waste is also a threat - plastic can entangle dolphins and be mistaken for food, causing longer term issues. Microplastics floating in the ocean enter the food chain through ingestion by marine species such as plankton, fish, dolphins and filter-feeding whales.
Are bottlenose dolphins endangered?
It depends where they are. Some populations, like the Lahille's bottlenose dolphin, are listed as Vulnerable by the IUCN, with around 600 left. The Black Sea bottlenose dolphin is listed as Endangered, with a population estimated at just a few thousand individuals.
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