…A question that sometimes occurs when I tell people that I study the sounds of the whales. Still, my very close non-scientists friends do think that I try to talk to dolphins. This might not be accurate since my research equipment and purpose of my study do not allow anything like this, but essentially I do try to spy on their “conversations”.

Meet Dory, a (fictional but funny) colleague of mine

One of the functions of sound in dolphins and whales is communication. Communication is a keyword in bioacoustics and is defined as being “the transmission of a signal from one organism to another such that the sender benefits from the response of the recipient”. There are different purposes that it serves living organisms and different ways to express it.

A primary purpose of communication is to attract and repel. Plants use chemical signals that get transmitted through the air or their roots, people use the smell of pheromones to attract each other, and skunks use the same signal to repel. Dogs and foxes use face and body gestures to express submission and aggression. Elephants use touch interlinking their trunks as a means of close communication. Especially for attracting mates, vision (peacock elaborated feathers) and sound (bird songs) are both very useful.


Do you get the message?
Do you get the message?

Though the most common well-known animal communication signal heard by humans is the bird song, there are all sorts of animals that rely on their hearing and vocal ability to succeed and survive. Whales, the modern giants, appear to be experts in the art of sound communication with different species each having their own sounds. They use these sounds to navigate, locate and capture prey, communicate about the environment and the availability of food or predators, and to attract mates or repel competitors.

Whale chat #alltheycareforisfoodandromance
Whale chat #alltheycareforisfoodandromance


Such acoustic signals may be (a) instinctive that is genetically programmed or (b) learned from others through social learning.

Social learning is the information moving through communication from one organism to another. This information then passing on is what we call culture. Without this transfer there would be no life, no evolution, no biology. Culture is why we have the Parthenon, the South Park, boy bands and the MIT. What you read, like this blog, that you may pass it on is culture.

Random example of culture: the Parthenon
Random example of culture: the Parthenon

Cultural transmission, the social learning from conspecifics is believed to occur in a number of groups of animals, including primates, cetaceans and birds, elephants and bats. Cultural traits can be passed through different paths.

Cultural transmission can be done vertically: from parents to offspring, obliquely: from the previous generation via non related individuals to younger individuals, or horizontally: between unrelated individuals from similar age classes or within generations.

cultural transmission
3 families of sperm whales and how they get their culture transmitted

Of the several types of social learning which have been recognized, imitation is particularly significant for the propagation of culture. Humans can imitate new sounds and learn how to use them correctly in social situations. This is called vocal learning which is considered to be one of the foundations of language.

My favorite example of imitation in the animal kingdom is the lyrebird of S. Australia, which has an unbelievable capacity for mimicry. During the breeding season in South Australia, the male lyrebirds spend six hours a day calling, doing their best to attract the ladies. They have the most complex syrinx (vocal organ in birds), and they make a remarkable use of it!

I know I am repeating myself since I have posted a video of the lyrebird before  but this time the famous mime has enriched its repertoire with more sounds that will make you wonder how and why… Check out the lyrebird’s latest hits here.

Next I would like you to meet Luna, another excellent mime; Luna is a male orphan killer whale. Luna has been all alone since the age of two, living off the coast of Vancouver Island, Canada. There, in 2001, Luna became popular for getting in close proximity to people, interacting with local boaters and perfectly mimicking boat noises. A tragic result of this interaction was the tragic death of Luna in 2006 due to a tugboat collision!

Culture, through social learning, has been studied and papers have been published mainly in only four species of cetaceans: (1) the humpback whale, (2) the sperm whale, (3) the killer whale, and (4) the bottlenose dolphin.

Humpback: the Diva

Humpbacks are the most popular singers of probably all the non-human mammals. They have even released CDs with their songs ! When we think of whale songs the humpback is what we have in mind. They represent the best understood horizontal culture of cetaceans.

The males produce series of vocalizations that form songs used in sexual selection (through mate attraction and/or male social sorting). Their songs are very complex and can be heard mainly in breeding grounds and whales can hear them up to 10 km (about 6 miles) away. Whales sing the same song for hours and hours. Populations within an ocean basin have similar songs with this similarity dependent on geographical distance between populations.

Humpbacks can change their song after hearing other songs. A terrific example takes place in the southern ocean where the songs are horizontally transmitted from eastern Australia in the west across the region to French Polynesia in the east. The songs have been documented radiating repeatedly across the region from west to east, usually over a period of two years. The result: soon the song that was recorded on the east region is now fully replaced by the west region hit. This seems to me to be really similar to our music culture transmission.


Killer whales: The Intellectuals

The Sea Pandas (as some marketing teams have proposed renaming killer whales to help promote their conservation) are highly social.

The cheeky ones
The cheeky ones

The populations off the west coast of Canada have been studied for decades and are divided in different ‘‘types’’: the residents, transients and offshores. These 3 different types have diverse feeding preferences and subsequent vocalizations. The residents feed on fish and are highly vocal, the transients feed on marine mammals and are much quieter to not reveal their presence to their prey that has good hearing abilities. The offshores are also highly vocal and feed on sharks and rays.

Extroverted vs. Introverted (Resident vs. Transient)

Killer whales that are separated by great geographical distances have completely different dialects. An analysis of Icelandic and Norwegian killer whale pods revealed that the Icelandic population made 24 different calls and the Norwegian whales made 23 different calls, but the two populations did not share any of the same calls.

Besides dialects, killer whales have been shown to learn vocalizations from other species. Yes, they speak foreign languages! At a water facility, where they socialized with bottlenose dolphins, they changed the types of sounds they made to resemble those of their neighbors.

If I was not so enthusiastic about the sperm whales, killer whales would definitely receive most of my scientific admiration. They have evolved outstanding sophisticated hunting techniques and their vocal behavior is impressive, being specific to certain groups and passed across generations. Killer whales are great examples of cultural organisms.

Keeping these animals in captivity sounds like  even less of a good idea now, right?

Bottlenose dolphins: the Eponymous

Bottlenose dolphins are well known for their signature whistles. They have stereotypical signatures attributed to each individual that work as their name. This helps to maintain contact between mom and calf or between individuals in a group. Each bottlenose dolphin has its own unique whistle and it uses it to broadcast their location and identity to others.

3 different whistles from different individuals. Hard to call a dolphin by its name...
3 different whistles from different individuals. Hard to call a dolphin by its name…

Most of the characteristic whistles are usually fixed for all the lifetime of the dolphin. However in some cases, when a male dolphin leaves mom and joins with other males to form an alliance (which might last for decade), their distinctive whistles converge and become very similar. So the longer they stay together the more similar their whistles become. Based on the same reasoning, I can’t understand why my English accent is still the same after three years living in USA!

Sperm whales: the Bignose

Sperm whales are among the loudest animals on Earth, and my favorite (not sure if I have already mentioned my preference). They owe this to their huge nose which functions as a massive click producer. They also have the biggest brain. They produce a variety of loud and distinctive types of clicks for different functions. One of these types of vocalizations is called coda. It is stereotypical patterns of clicks resembling Morse code, and frequently serves social purposes. Codas are usually heard when the group of animals rest or socialize at the surface of the ocean. Similar codas used by one group may help maintain group cohesion after its members are done feeding.

Chilling after dinner

It is thought that each sperm whale has its own individually distinctive coda pattern and it has been reported that groups within one geographic area tend to have more similar codas than groups from further away. The “five regular” call is one of the few codas that all sperm whale groups around the globe use in their regional dialects; while the “plus one” type seems to be specific to Mediterranean inhabitants. These vocal behaviors are transmitted vertically, and loosing members of the population may seriously impact the transmission of this cultural trait that carries important information content vital for the survival of the population.

The "regular 5" and the "plus one" codas
The “regular 5” and the “plus one” codas



We don’t need to watch Interstellar to search for life in different solar systems and unknown worlds. Like Anne Stevenson said: “the sea is as near as we come to another world”.  The ocean is vast largely undiscovered. We can consider the open sea an intriguing new wet universe. In interstellar, communication or miscommunication played an important role and turned out to be vital for rescuing the world. Father and daughter that could not directly speak to each other used binary code to transmit their messages through different dimensions. The cetaceans also transmit their messages through codes that we try to identify and understand. It is vital for their world to be able to use these sounds to communicate. You can correctly guess that we are using their home for our anthropocentric purposes and we are being very noisy neighbors, polluting their ocean and impacting their survival. This can be changed… If you are looking for New Years resolutions…

Like in the movie, it’s not Them that will help us save the world. No external factors are required, all the power is in us!


Happy, quiet and peaceful holidays to y’all!!

This post was inspired by the presentation that me and Selene gave on Saturday 12/13/2014 for the Oregon Chapter of the American Cetacean Society entitled: “Do you speak whale?”.

Whistling while you work is only acceptable if you are one of the 7 dwarves. You are too tall to be a dwarf; or the Snow White”, I can imagine Holger, my advisor, saying.

Some people are whistle sensitive
Some people are whistle sensitive

In reality Holger is too wonderful to mind if I whistle while I work or not. But I actually don’t. Which a few unfortunate people that have witnessed it will unanimously agree that it is for the common good.  Nevertheless, I get to work on whistles!

The animals that I work with are notorious whistlers! You might consider yourself skillful in whistling, an expert in whistle-flirting and dexterous in folding you tongue and sending loud whistles miles away to your friends on the other side of a soccer field, but that is just like whistling against the wind to dolphins. If you compare your selves to their whistling capabilities you will be embarrassingly defeated. (In every case, several analysts and Experts of Life support that comparing yourself to others can only make you unhappy.)

Dolphins and killer whales, which belong to the Delphinidae family, produce 3 types οf sounds:
1. Clicks used for echolocation that help them navigate, find food and capture it,
2. Burst pulses that are rapid rate clicks and serve similar purpose but with higher definition, and
3. Whistles

Types of delphinid sounds and how they look (frequency on the y axis and time on the x axis)
Types of delphinid sounds and how they look (frequency on the y axis and time on the x axis)

Dolphin whistles are generally of narrow bandwidth and frequency modulated sounds that commonly last for half to a few seconds, much longer than the individual clicks and they are of lower frequency. Their characteristic lower frequency allows them to propagate in longer distances and their function is believed to be primarily social.
Whistles are considered to be a product of the same mechanism that generates the clicks: air that goes through the nasal passages of the dolphin’s head. The odontocetes (toothed whales) don’t literally vocalize, since they don’t use vocal cords like we do. They use the air that enters their blowhole to make sound by canalizing it through passages and their melon (the fatty tissue that makes their forehead look rounded). This video: Echolocation and sound production mechanism can give you a good representation of it.The production of whistles seems to require larger volumes of air which makes them unsuitable for echolocation since air volume is reduced by hydrostatic pressure during diving and foraging. Instead, the dolphins are thought to use them for communicative purposes, to stay in touch with their gang in the vast oceans.

I am particularly interested in the whistles. Especially the dolphin whistles. As I described at my previous post, this past summer I collected a bunch of different dolphin species’ acoustic recordings from the Aegean Sea. These recordings will help me create a sound library for the dolphin populations that dwell the eastern Greek Seas, essentially a whistle-bank for the populations in that area.

In addition to the different dialects or accents that the dolphins populations have and I have previously mentioned, they also have names that the scientists call signature whistles. Specifically, the bottlenose dolphins are known to learn and recognize whistles that are unique for every individual in a group and these whistles are used to broadcast the identity and location of the animal that produced them. This characteristic is crucial for the contact between mother and offspring, for feeding and protection from predators. Most of the characteristic whistles are usually unchanged for all the lifetime of the dolphin. But occasionally, when the male dolphins leave their mom to experience the adult life in a group of  other males their distinctive whistles actually converge and become very similar!

Besides the dolphins, more animal species seem to find names meaningful. A striking example is the one of the green-rumped parrotlet that lives in Venezuela.

Touch is communication too. Even if it happens with the beaks.
Touch is communication too. Even if it happens with the beaks.

This cute little green parrot is attributed a whistle name by its parents and it gradually learns it by them. In this delightful video  you can see how the researcher discovers the learning ability of the parakeets in contrast to the genetic encoding of communication mechanisms in this species.

Birds have actually been the very first research target of bioacousticians. Even though they can fly away and escape the

Some birds can be so weird (maybe is the flying...)
Some birds can be so weird (maybe is the flying…)

claws of their scientific fate, it is still easier to study them than the marine mammals that slip away in the open ocean. A remarkable example of unusual bird vocalizations and intriguing to research specie is that one of the superb lyre bird of

South Australia! In this specie the male, in order to attract the girls, besides the elaborated dance and feather display, can also imitate the calls of more than 20 other bird species. This bird is so good at mimicking others that it can confuse even the birds that it is copying.

But the lyrebird is not only imitating other birds; it has evolved his skills beyond living organisms. A real master of mimicry! It is able to incorporate in its repertoire any sound that hears in the forest. Like that of a camera shutter, or a car siren, or chainsaws! Or the sound of the fridge door opening and closing (would be the case if my house was its habitat)…

FAD (Fridge Amnesia Disorder)

But seriously, I am not making this up! Check this jaw dropping video to see for yourselves. This bird is either desperate to reproduce or the females don’t really know what they want.

At this point I will paraphrase Snow White; whistling is a lot of work!

Some people seem to have a talent in whistling. They can whistle entire songs, or the more eccentrics can whistle the whole alphabet. They use their lips, teeth and tongue to do it, their fingers in all sorts of strange formations, their palms, and a wide range of imaginative accessories. Personally, it took me several weeks at the age of 23 to learn how to whistle.  Soon I was glad for my achievement as it turned out to be a remarkably useful skill when I got a dog. Loud, piercing and sharp… a whistle is hard to ignore. Even if you are a dog.

You might be surprised to discover that whistles are not used uniquely by animals for their communication. Since the Antiquity people used whistles to communicate in very long distances. Whistles can travel much longer than speech and can overcome ambient noise much more effectively. You might have noticed that often people that work in bars use them to signal among them.
In the natural environment, in locations where the landscape consists of deep valleys and steep ravines, whistled languages were common within some human communities. Before the 1940s, when the phone was not widely used yet, people replaced words with whistles to send messages that would overcome distance issues. Whistles have the ability to travel up about to two miles (3.2km), which is much further and with less effort than shouting. Initially these languages were invented and largely used by shepherds, and for long time they were a common way in agricultural communities at isolated villages to transmit news, events or emergencies.

Examples of these communities and their whistled languages still exist! The cases of the Village Antia in the Greek island of Evia, the Kuskoy Village “Bird Village” in Turkey, and the “Silbo” language at La Gomera at the Canary Islands in Spain, are the exceptional cases of alive whistled languages.
In this uncommon language, consonants are distinguished by changes in pitch over different intervals of time and the whistle is a substitute of the original language which gets compressed. The whistled language is not a code, has rather defined characteristics.

Evidently marine scientists are charismatic people with variable interests and acute curiosity . It appears that Cousteau was also interested in analyzing the characteristics of La Gomera’s whistled language!


Cousteau actually studied the Silbo and published an accurate description at the “New Scientist” of 1958!

Nowadays these languages are slowly becoming extinct. However, it is encouraging that in La Gomera at least, the Canary Islands’ government links the whistled language to the identity of the people and recognizes its value as part of the traditional culture in this area and try to preserve it. As a result, La Gomera is one of the few places in the world where children learn to whistle in schools!

Aristotle in the History of Animals wanted to describe what separates animals from people. What is that makes us different: is it the reason, the language or the laughter? Several recent researchers and philosophers suggest that it is the culture. But what do we define as culture. Is it the ability to learn, to mimic, the language? It turns out that both people and dolphins use certain sounds, in this case whistles, in form of language in order to communicate. The human community considers the human whistled language as a cultural heritage worth protecting and maintaining. Similarly, without me trying to attribute human qualities to the animals, cetaceans have social learning skills and cultural capacities that are advanced and worth maintaining as well. It is our doubtless responsibility to protect them.

During my childhood, my mom would wake me up every morning with whistling melodies. I surely despised it. Mainly the wake-up- in-the-morning part. The whistling part was also very disturbing, especially because it was such an effective mean to get me off the bed! Now I am particularly attracted by whistled melodies and I am a fool for songs that include them. So I prepared my favorite Top 10 of songs with whistling, with extra 2 Greek tracks. #1 on the list is my current wake-up-song. I love it! Not the wake-up part, I still cannot get over that…

Niki’s Whistling Top10
1. Truth– Alexander
2. Tire Swing– Kimya Dawson
3. Don’t Worry be happy-Bobby McFerrin
4. Home-Edward Sharpe and the Magnetic Zeros
5. Tighten up– Τhe Black Keys
6. Pump up Kids-Foster for the People
7. Wind of change– Scorpions
8. The dock of the Bay– Ottis Redding
9. Twisted Nerve– Kill Bill 1 OST
10. Young Folks– Peter Bjorn and John

11. Το ποδηλατο (the bicycle)- Ελένη Βιτάλη
12. Συννεφούλα (the little cloud)- Διονύσης Σαββόπουλος
**Stay tuned in our “vocalizations” through our tweets @ORCAAlab and our facebook updates at Orcaa Lab**