In the first part of the animated film series Despicable Me, Agnes, the cute, wide-eyed salopette-wearing little girl whose ponytail challenged Newton’s gravity and projected right towards the sky, had a single wish. Now that she and her two orphan sisters were adopted by Gru, Agnes wanted to find a real unicorn after she received a fluffy plush one at the Super Silly Fun Land.
It was not until the third film, however, that Agnes found her real unicorn out in the woods. When she did, she went bananas and immediately fell in love with it to the point that she did not realise it was not a unicorn. Instead, it was a single-horned baby goat with a cute little wattle and eyes just as wide as Agnes’.
At first, her sister could not tell her, but then Gru did. He so aptly explained to Agnes that there was no such thing as a unicorn. Little did Gru, Agnes, and pretty much most of the world population know that unicorns do exist! In fact, they have lived on earth for millions of years and are currently residing in one of the uttermost places on our planet.
Would you like to know more about those enigmatic unicorns of the sea? Then, read on.
Although National Geographic insists on describing them as “weird”, we are pretty sure Agnes would scream in joy and shout, “It is so magical!” once she sees a narwhal.
Narwhals are a species of whales whose most captivating aspect is a long, straight spiral tusk protruding from their upper jaw. It pretty much resembles the legendary unicorn’s horn, except that it is not pink. Narwhals primarily inhabit the Arctic Ocean and the adjacent seas. Such an extreme habitat suggests how hardcore these creatures are.
It is not known exactly when narwhals were discovered. Yet, apparently, they were known to the indigenous Arctic peoples for centuries, just as turkeys were known to the Native Americans but not to the rest of the world. The first known record of a horned creature that looked like a narwhal was a 1555 drawing by the Swedish writer and cartographer Olaus Magnus.
Then, that same creature appeared once again in the Systema Naturae. This is an influential work in the history of biology, written by the Swedish scientist Carl Linnaeus and first published in 1735. This book, by the way, laid the groundwork for the science of classifying organisms, which we call and explained many, many times before, the taxonomy hierarchy.
Since then, scientists have studied narwhals as closely as the harsh environment of the Arctic and the animals’ behaviour allowed. They got to learn so much impressive information about them, which can fairly classify those whales as majestic.
As we wish you recall from our previous stories on animals, the modern taxonomic classification is a system used to organise the millions and millions of extant and extinct organisms so it is less intimidating for scientists and biology enthusiasts to study them. There are eight main levels in this system, organised from general to specific as domain, kingdom, phylum, class, order, family, genus, and species.
Narwhals belong to the class Mammalia. This means they, like many other creatures as well as us, have backbones, breathe through lungs, give birth, and produce milk to nurse their babies. However, there are thousands and thousands of different mammals living on earth, so this class was further divided into 29 orders, one of which is called Cetacea and includes all whales, dolphins, and dolphin-like aquatic mammals called porpoises.
Yet, again, whales, dolphins and porpoises are so many and distinct. So, scientists divided the order Cetacea, to which they all belong, into 10 families. One of them is the Monodontidae family, which has two genera: Monodon and Delphinapterus, each with only one species, narwhals and beluga whales. There used to be more genera and species in this family, but they all, sadly, went extinct.
As scientists propose, over 11 million years ago, both narwhals and beluga whales did not exist, yet dolphins did. At some point, some dolphins started developing different physical and behavioural traits, which, after countless years, made them evolve into beluga whales. The same thing happened with a group of beluga whales, and after some millions of years, they turned into narwhals.
That is why narwhals share many similarities with beluga whales, yet they still possess many other distinctive characteristics that make them unarguably unique.
So, what exactly do those sea unicorns look like?
Compared to orcas and dolphins, narwhals are quite medium-sized. They have the same robust cylindrical body as their cousins, but they lack the dorsal fin and the long snout. Their heads are long, their mouths are small, and they have teeth.
Like most mammals, male and female narwhals possess slightly different physical characteristics, with males typically being bigger.
For instance, a male narwhal has a mean length of 4.1 metres, while females are 3.5 metres at the maximum. Males can reach a weight of 1,600 kilos, while females never exceed 800 kilos.
Narwhals have a relatively long lifetime, ranging from 25 to 50 years. Males mature and can mate at the age of 11 to 13 years, while females can reproduce at a much younger age, only when they are between five and eight years old.
Another difference that sets the two narwhal genders apart is the tusk, which males exclusively possess—we will talk more elaborately about the tusk in the next section.
Narwhals, both male and female, have white skin with patterns of black and brown mottled pigmentation on the back. As males age, their dark skin goes pale until it turns completely white in old individuals, which makes them look more like beluga whales, plus the tusk.
As we mentioned, narwhals do not have dorsal fins like dolphins and orcas, not even a tiny small one like that in a humpback whale. Usually, dorsal fins are used to help the marine mammal stay stable, not roll on its side, and swim in a straight line. Taking away the dorsal fin, however, does not mean narwhals were left to lose balance or drift while swimming. Instead, they were given dorsal ridges.
A dorsal ridge is a raised structure, about five centimetres high, found along and covering half the midline of the narwhal’s back. Besides helping the whale stabilise and swim with ease, the dorsal ridge also reduces heat loss dramatically. This fact makes scientists believe that narwhals developed this structure to adapt to the frozen environment they live in.
Aside from the dorsal ridge, narwhals also have short flippers and flukes that aid with swimming and locomotion. A fluke is the flattened, paddle-shaped structure at the end of the narwhal’s tail, a characteristic feature it shares with its whale and dolphin cousins.
Interestingly, narwhal flukes show a fascinating difference between males and females. Males have flukes with a slightly concave leading edge often used to compensate for the drag caused by their long, heavy tusks. Female flukes, on the other hand, have swept-back leading edges, making them look more like dolphin flukes.
Like polar bears, all penguins, seals, and many other marine and even land animals living in extremely cold habitats, narwhals have a layer of fat beneath their skin called blubber. This layer mainly insulates the narwhal’s body and maintains its temperature as well as its position in the water column to control buoyancy.
The blubber also acts as the whale’s pantry. It provides a source of calories that can be utilised during periods of fasting or when food availability is limited.
Now, to the unique characteristic that distinguishes narwhals from all marine mammals and makes them little Agnes’ only hope in life: the tusk.
Like those in elephants, a male narwhal’s tusk is a long canine tooth projecting from the left side of the upper jaw, through the lips and out to the water. It is hollow, made of a hard, dense tissue known as dentin, and has a spiralled outer structure that develops with age.
Male narwhals are not born with tusks, yet they start to grow them when they are around three to four years old, although they may not fully develop until later in life. The average tusk length is usually between 1.5 and 2.5 metres, but it may sometimes grow to measure three metres in some individuals.
Female narwhals generally do not grow tusks. Yet, very rarely, some females may develop small tusks or tusks that do not fully protrude.
Narwhal tusks have a purpose; they sure do, just like everything else in this universe. It is only that scientists have not yet agreed on which purpose or purposes narwhals use their tusks for. This will probably remain a subject of scientific debate until we can more closely and consistently study those magical creatures.
As scientific research revealed so far, the tusk is one of the extremely sensitive organs in the narwhal’s body. It is packed with millions of nerve endings that can detect changes in water temperature. This definitely helps narwhals navigate the frigid Arctic environment.
However, the tusk’s purpose goes beyond just feeling the cold. Scientists now believe male narwhals might rub their tusks together, not just to show off dominance but to share information about the waters they have explored. Recent footage even revealed that narwhals can use their tusks to stun fish before catching them for a meal, adding another surprising trick to their repertoire.
Since females do not have tusks and still live longer than males, scientists concluded that tusks are not crucial for survival, but they play a bigger role in attracting mates. In fact, most scientists believe that males with longer, more spiral and robust tusks look more attractive than their counterparts to females.
In fact, many scientists strongly believe that males may use their tusks to compete with other males and prove to females that they are worthy of their love. With tusks, males also establish dominance within the social hierarchy.
Narwhals, like dolphins, whales, monkeys, and us, have lungs and breathe air. Yet, because they live in water, they have special adaptations that allow them to survive and thrive in their aquatic environments.
For instance, every narwhal has a blowhole located on the top of its head and connected to its respiratory system. It is the nostril through which the narwhal takes in air when it surfaces. When a whale dives, its blowhole closes to prevent water from entering the respiratory system.
Diving.. yes.
Narwhals are indeed skilled divers known for their impressive diving abilities, which enable them to forage for food at significant depths. They are capable of diving to depths of around 800 to 1,500 metres and can stay submerged for up to 25 minutes or more, though typical dive durations are shorter. Such an amazing skill is facilitated by several adaptations.
First of all, narwhals have large lungs and high concentrations of myoglobin. Basically, this is a protein that stores oxygen in the muscles and allows these whales to remain submerged for extended periods. The narwhal’s rib cage is also flexible and can compress as the whale’s descends, withstanding immense water pressure and reducing the risk of injury during deep dives.
Besides the blubber that helps them float, narwhals can adjust their buoyancy by regulating the amount of air in their lungs, which allows them to ascend and descend in the water column with ease. Their streamlined bodies also minimise water resistance and enable efficient movement through the water, aiding in diving.
So many animals living on earth migrate by leaving their original habitat to a new land mainly to find better environmental conditions and more food and to escape from predators. This way, they can maximise their chances of survival and reproductive success.
Many animals do so, and narwhals are no different.
Every year, narwhals travel between summer and winter homes. In summer, they prefer shallow, ice-free coastal areas, which become accessible as the ice melts. During this time of the year, these areas usually teem with prey and provide a rich feeding ground for narwhals to fatten up for the long winter ahead.
Summer is also when narwhals socialise, often hanging out in groups, called pods, of 10 to 100 individuals. They mate during summer, too. The calmer, shallower waters near the coast offer safer birthing grounds for females. This reduces the risk of predators and allows calves easier access to the surface for breathing and nursing.
As winter approaches, the waters near the coast freeze over. Narwhals then migrate to deeper offshore regions beneath the pack ice. These areas have higher concentrations of Greenland halibut. This brown-grey fish is a favourite food source that helps narwhals sustain their diet through the long, food-scarce winter months.
Narwhals depend on openings in the sea ice, called leads, for breathing and navigating. Leads can differ in width from a few metres to several kilometres and can extend for many kilometres in length. Unfortunately, if these leads are further away than the whale can reach on a single breath or if the ice is way too thick for the narwhal to break, the animal may suffocate and die.
Magic does not stop there, however. Narwhals can also navigate their way through the deep, dark ocean, locate prey, and communicate with one another from afar using echolocation, the mystical sensory system they share with dolphins and bats.
So, exactly does it work?
Narwhals emit high-frequency sound waves through their nasal passages near their blowholes. When the waves strike any object, they bounce back and return as echoes but with lots of data. By analysing the timing and intensity of the returning echoes, narwhals can perceive their surroundings and determine the location, size, shape, and texture of nearby objects.
Narwhals also emit other sound waves to communicate with their pod members. Interestingly, they can adjust these waves to target a single individual or a group, near or far.
As we just mentioned, narwhals breed during the warmer seasons when they migrate from the deep to the shallow food-abundant water around the coasts. Males should be at least 11 years old, while females need to only be between six and eight years old to mate.
Usually, female narwhals stay pregnant for 15 months, and then they give birth to a single calf that is as long as 1.5 metres, on average. It is not until two or three years that the female can reproduce again, and this is about the same period the calf takes to nurse and grow independent.
As mammals, calves primarily depend on their mothers’ milk, which is abundant in fat and nutrients, to grow and thicken their blubber. They also stick to their moms like glue and accompany them everywhere, and this is when their moms teach them the necessary skills to survive in the Arctic Ocean, such as how to find food and the best way to escape from a predator.
Although they are listed as Least Concern (LC) on the IUCN Red List, with their numbers estimated at around 123,000 adults, narwhals happen to face a variety of threats, both natural and human-induced, which can impact their survival and long-term viability as a species.
First of all, the warming of the Arctic due to climate change is altering narwhals’ habitat. Changes in sea ice cover can disrupt narwhals’ access to breathing holes and hunting grounds, while warming temperatures may impact their prey species. Shipping, oil and gas exploration, and industrial development can also cause noise pollution, habitat fragmentation, and pollution, all of which disrupt narwhals’ behaviour, communication, and navigation.
While commercial hunting of narwhals is prohibited under international agreements, some indigenous communities in the Arctic still hunt narwhals for subsistence purposes. Also, getting entangled in fishing gear, such as nets and lines, can cause injuries, impair movement, and lead to death.
Narwhals remain a captivating enigma of the Arctic seas. From their spiralling tusks and remarkable adaptations to their impressive migrations and super-duper echolocation, these underwater unicorns continue to spark our curiosity.
As research unveils more about their unique adaptations and social behaviours, one thing is certain: narwhals are vital players in the fragile Arctic ecosystem. Protecting their icy habitat and understanding the threats they face is crucial for ensuring their continued survival. With continued research and conservation efforts, we can safeguard the future of these magnificent creatures and the wonders they hold.
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