Bottlenose dolphins are almost universally the creatures that come to mind when one
hears the world “dolphin” - even though there are dozens of other species!
Bottlenose dolphins hail from the Tursiops genus,
however, like many animals we’ve covered here on AFF their classification is debated.
It’s largely agreed that there are two species of bottlenose dolphins - common bottlenose
dolphins (Tursiops truncatus) and Indo-Pacific bottlenose dolphins (Tursiops aduncus). There
may also be a third species called Burrunan dolphins (Tursiops australis) after the language
of Australian natives, though this has not been widely accepted in the scientific community.
We on AFF are happy to accept them because why not, but it is possible that bottlenose
dolphin classification could change significantly with more research.
Common bottlenose dolphins live throughout the ocean’s warmer waters
while Indo-Pacific and Burrunan dolphins are found mainly along the coasts of Australia.
Some groups of bottlenose dolphins, called pods, prefer to live closer to shore while
others like living out in the open ocean. While coastal living bottlenose dolphins are generally
slightly smaller than their offshore neighbors, on average a bottlenose dolphin is about 12
feet (3.66m) long once full grown with common bottlenose dolphins being the largest species.
In color, bottlenose dolphins can range from pale grey to dark charcoal.
Their dorsal, or top, half is darker than their ventral,
or bottom half which can appear nearly white. Color varies through individual dolphins, and
older dolphins can even sport speckled patterns. It’s like they’re developing liver spots!
Bottlenose dolphins can live to be older than 50 with females living slightly longer than males.
The age they’re ready to mate can be anywhere from 5 to 15 years old with females maturing
slightly faster than males. The age of sexual maturity largely depends on how long bottlenose
babies end up staying with their mother. Female bottlenose dolphins gestate for a year. The
baby is born live and there are tiny little hairs growing on her nose. Like all mammals,
dolphins have hair, but theirs begins to fall out as they swim more! They also drink milk,
and a dolphin baby may drink her mother’s milk for two years or longer - there was even report
of a male bottlenose baby who stayed with his mom for more than a decade! Talk about a Mama’s boy…
Bottlenose dolphins learn to hunt during their time with their mother. They’ll eat fish,
cephalopods, and crustaceans, and they all have different ways of collecting these meals.
It’s pretty widely believed that dolphins are some of the smartest animals in the
world. One captive dolphin named Kelly started a game of gull baiting in order to receive more
fish from her trainers which was then learned by her tankmates; some dolphins have been taught to
open puzzles in a collaborative effort in order to reach fish inside; others seem to be able to
recognize their own reflection and even actively watch TV! So, it’s no surprise that bottlenose
dolphins - specifically Indo-Pacific bottlenose dolphins - have been observed using sea sponges
to protect their noses while foraging on the ocean floor. This phenomenon is the first
recorded use of tools by dolphins - a trait not shared throughout most of the animal kingdom.
Although dolphins are smartypants, they’re still not completely out of harm’s way.
Because some bottlenose dolphins live close to shore, they intermingle with humans frequently.
Often, bottlenose dolphins are caught in fishing nets - an interaction which can prove
fatal. They’re also in danger of impact from boats especially when they’re enticed
to boats with bait and fishing leftovers. Actually, it’s completely illegal to feed
any kind of dolphin in North America as well as some other parts of the world,
and they should be given distance when observing them to help keep them safe.
Sharks, including tiger, bull, and great white sharks also attack bottlenose dolphins and seem
to specifically target bottlenose babies. This can be a contributing
factor to higher mortality rates in younger bottlenose dolphins. Plus,
many adults bear scars relating to shark attacks. I suppose it makes sense that dolphins themselves
can be pretty brutal if they have to worry about sharks while they’re still an infant.
In general, though, bottlenose dolphins are curious and playful creatures who form friendly
bonds in pods that can change throughout the day and can even include other animal species.
It’s atypical to see a single, roving bottlenose dolphin - though it does happen! Their energetic
and fun-loving attitude has landed them as a symbol of positivity to us landlubbers.
For more facts on bottlenose dolphins, take a look at the links in the description - there
is lots more to learn than what we could fit into just one episode.
We would like to thank the Victoria Museum and Gallery for their awesome
requests - there are some super animals coming up so be sure to stay tuned in to Animal Fact Files.