you're reading...


Where’s that accent from? Dolphins from different seas talk in different whistles

Excerpt: Dolphins talk to each other by whistling, but whistle sounds vary between seas. What causes those differences in dolphin accents?

Study: La Manna, Gabriella, et al. “Whistle variation in Mediterranean common bottlenose dolphin: The role of geographical, anthropogenic, social, and behavioral factors.” Ecology and evolution 10.4 (2020): 1971-1987. https://doi.org/10.1002/ece3.6029

There are a multitude of different accents in the world that vary with  where someone calls home. This holds true in the underwater realm as well.

Dolphins communicate to each other in whistles – high-pitched sounds that last between 0.1 and 4 seconds. Most of those sounds are beyond the human hearing range, but dolphins successfully use them to recognize each other and coordinate with the rest of their group underwater. 

But do all dolphins sound the same? A research team at a non-profit organization MareTerra Onlus in Italy investigated how whistles differ between dolphins from different parts of the ocean. 

The scientists identified two populations of bottlenose dolphins – one living near the shore of Croatia in the Adriatic sea, and the other one by Sardinia in the Mediterranean sea, separated by Italy.

Croatia is by the Adriatic sea, and Sardinia is surrounded by the Mediterranean and other seas. The Italian peninsula separates the two regions. Image credit: Wikimedia Commons








Waves and whistles

Members of the research team collected their data on dolphin whistles by getting into boats and patrolling the sea to find dolphins. Upon sighting them, the researchers took pictures and observed the number of dolphins and how they interacted with each other. To record their whistles, the scientists used a device called a hydrophone – a microphone designed to record sounds underwater.

Back in the lab, the researchers examined the recordings, paying attention to frequencies of the whistles. Frequency, also called pitch, refers to how often a sound wave oscillates while travelling to our ears. To us, low-frequency noises sound low, like thunder, and high-frequency sounds are high-pitched, such as squeaks of a dog toy.

Dolphins vary their whistles by changing their pitch, even within the same whistle. The researchers analyzed the whistles based on their length and pitch, using a statistics technique called principal component analysis. This technique identifies patterns within large amounts of data and helps pinpoint why they happen. The scientists searched for signature whistles, which are specific to individual dolphins and change their pitch in the same pattern, and compared the whistles of dolphins from the shores of Sardinia and Croatia.

Speaking in tongues

As expected, geographical location was an important source of variation in whistles. Croatian dolphins whistled in higher frequencies when there was a lot of ambient sea noise around them. Sardinian dolphins tended to produce shorter whistles in lower frequencies.

Bottlenose dolphins communicate with each other in whistles. Image credit: La Manna et al. (2020)

Dolphins from different seas also whistled differently if their calves were around. The whistles of Croatian dolphins were more high-pitched in the presence of their babies. By contrast, Sardinian dolphins “spoke” in lower frequencies when calves were swimming in close proximity. These regional differences in baby talk also support the finding that dolphin communication varies between geographical locations.

Additionally, the researchers uncovered an interesting trend. When dolphins from both Sardinia and Croatia were part of a large group, they produced longer, higher-pitched whistles and changed pitches within a single whistle more often.

A language barrier?

The study affirmed that dolphins from different waters sound different. These distinctions in pitch became more pronounced when there were other sounds or dolphins around. 

Scientists are not yet sure what nuanced pitch changes in dolphin whistles mean or why ocean noise changes how dolphins from the shores of Croatia, but not Sardinia, communicate. Marine experts are also a long way from deciphering what dolphins whistle to each other under the sea. But for now, we can be sure that dolphins enjoy a complicated communication system that is not entirely dissimilar from human languages, to the point of varying with geographical locations.

Are the differences in the whistles of Croatian and Sardinian dolphins as dramatic as the gap between the human Italian and Croatian languages? Or would a dolphin from the Adriatic sea be perfectly able to chat with its Mediterranian cousins? Future studies will reveal just how diverse dolphin languages are.


No comments yet.

Post a Comment


  • by oceanbites 3 months ago
    Happy Earth Day! Take some time today to do something for the planet and appreciate the ocean, which covers 71% of the Earth’s surface.  #EarthDay   #OceanAppreciation   #Oceanbites   #CoastalVibes   #CoastalRI 
  • by oceanbites 4 months ago
    Not all outdoor science is fieldwork. Some of the best days in the lab can be setting up experiments, especially when you get to do it outdoors. It’s an exciting mix of problem solving, precision, preparation, and teamwork. Here is
  • by oceanbites 5 months ago
    Being on a research cruise is a unique experience with the open water, 12-hour working shifts, and close quarters, but there are some familiar practices too. Here Diana is filtering seawater to gather chlorophyll for analysis, the same process on
  • by oceanbites 6 months ago
    This week for  #WriterWednesday  on  #oceanbites  we are featuring Hannah Collins  @hannahh_irene  Hannah works with marine suspension feeding bivalves and microplastics, investigating whether ingesting microplastics causes changes to the gut microbial community or gut tissues. She hopes to keep working
  • by oceanbites 6 months ago
    Leveling up - did you know that crabs have a larval phase? These are both porcelain crabs, but the one on the right is the earlier stage. It’s massive spine makes it both difficult to eat and quite conspicuous in
  • by oceanbites 6 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring Cierra Braga. Cierra works ultraviolet c (UVC) to discover how this light can be used to combat biofouling, or the growth of living things, on the hulls of ships. Here, you
  • by oceanbites 7 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Elena Gadoutsis  @haysailor  These photos feature her “favorite marine research so far: From surveying tropical coral reefs, photographing dolphins and whales, and growing my own algae to expose it to different
  • by oceanbites 7 months ago
    This week for  #WriterWednesday  on Oceanbites we are featuring Eliza Oldach. According to Ellie, “I study coastal communities, and try to understand the policies and decisions and interactions and adaptations that communities use to navigate an ever-changing world. Most of
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Jiwoon Park with a little photographic help from Ryan Tabata at the University of Hawaii. When asked about her research, Jiwoon wrote “Just like we need vitamins and minerals to stay
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring  @riley_henning  According to Riley, ”I am interested in studying small things that make a big impact in the ocean. Right now for my master's research at the University of San Diego,
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Gabby Stedman. Gabby is interested in interested in understanding how many species of small-bodied animals there are in the deep-sea and where they live so we can better protect them from
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Shawn Wang! Shawn is “an oceanographer that studies ocean conditions of the past. I use everything from microfossils to complex computer models to understand how climate has changed in the past
  • by oceanbites 9 months ago
    Today we are highlighting some of our awesome new authors for  #WriterWednesday  Today we have Daniel Speer! He says, “I am driven to investigate the interface of biology, chemistry, and physics, asking questions about how organisms or biological systems respond
  • by oceanbites 9 months ago
    Here at Oceanbites we love long-term datasets. So much happens in the ocean that sometimes it can be hard to tell if a trend is a part of a natural cycle or actually an anomaly, but as we gather more
  • by oceanbites 10 months ago
    Have you ever seen a lobster molt? Because lobsters have exoskeletons, every time they grow they have to climb out of their old shell, leaving them soft and vulnerable for a few days until their new shell hardens. Young, small
  • by oceanbites 10 months ago
    A lot of zooplankton are translucent, making it much easier to hide from predators. This juvenile mantis shrimp was almost impossible to spot floating in the water, but under a dissecting scope it’s features really come into view. See the
  • by oceanbites 11 months ago
    This is a clump of Dead Man’s Fingers, scientific name Codium fragile. It’s native to the Pacific Ocean and is invasive where I found it on the east coast of the US. It’s a bit velvety, and the coolest thing
  • by oceanbites 11 months ago
    You’ve probably heard of jellyfish, but have you heard of salps? These gelatinous sea creatures band together to form long chains, but they can also fall apart and will wash up onshore like tiny gemstones that squish. Have you seen
  • by oceanbites 12 months ago
    Check out what’s happening on a cool summer research cruise! On the  #neslter  summer transect cruise, we deployed a tow sled called the In Situ Icthyoplankton Imaging System. This can take pictures of gelatinous zooplankton (like jellyfish) that would be
  • by oceanbites 1 year ago
    Did you know horseshoe crabs have more than just two eyes? In these juveniles you can see another set in the middle of the shell. Check out our website to learn about some awesome horseshoe crab research.  #oceanbites   #plankton   #horseshoecrabs 
WP2Social Auto Publish Powered By : XYZScripts.com