Of unicorns and narwhals

The ocean is filled with species we know little about because of their rarity, their shyness, or their location which makes them difficult to study. Researchers are using new techniques and equipment to gather valuable information about these unicorns of the sea, a name sometimes applied to the elusive narwhal.

In search of the unicorn

 By definition, a unicorn is something that is rare to find or hard to catch. Most people think of a creature with a long spiraled horn when they hear the term unicorn. Many an artist has depicted the unicorn as a white horse-like creature with flowing mane and tail and a horn protruding from its forehead. There are also creatures that live in the ocean that are occasionally referred to as unicorns of the sea. Although difficult to find, unlike the horse-like unicorns, there is scientific proof that the spiraled “horned” creatures do exist.  

Tracking an elusive unicorn 

Rare animals are often designated as endangered species. Under the Endangered Species Act, this designation requires that the animals be protected from extinction. To achieve this, researchers first need to locate and then monitor the animals in order to design a plan for their protection. The task can involve multiple steps and numerous years to complete but, as the existence of sea otters, brown pelicans, and bald eagles demonstrate, the results can be successful. A key part of protecting rare animals is determining the factors that threaten survival. Sometimes the methods used to study the animals may sound as remarkable as the animals themselves.  For example, researchers have developed a technique for collecting air samples in order to look for the genetic material known as DNA. Skin, hair, saliva, and other cells all contain this biological marker. Collecting the DNA is proof of the existence of the animal. One researcher described the technique as “literally sucking DNA out of the sky.”  

Scientists analyze water samples for DNA as a way to confirm the presence of marine animals. In Western Australia scientists have found that sea water is an excellent way to study whale sharks. “Despite their large size, whale sharks are notoriously challenging to track. But like all marine species, whale sharks shed their unique DNA codes into the ocean – known as DNA or ‘eDNA’ – via skin, faeces (sic) blood, mucus, sperm and other biological material.” The whale shark DNA has been used to identify individual sharks something that had previously only been done by collecting tissue samples directly from an animal. This kind of information “could also help answer global population-level questions for other megafauna, such as sharks, rays, marine turtles, or dugongs.”  

Genetic information is also valuable in understanding a species’ population dynamics. As an example, in 2014 genetic testing of the Bryde’s whales found in the Gulf of Mexico led to a determination that these animals were actually a separate subspecies. As a result the Gulf of Mexico Bryde’s whale population was designated as endangered. The Gulf of Mexico Bryde’s whale has less than 100 individuals. It is considered one the most endangered whales in the world. The population faces “ongoing threats from oil and gas development, vessel strikes, increasing ocean noise, and entanglement in fishing gear.”  

Much else can be learned from collecting samples from the ocean. Researchers from the New England Aquarium in Boston, Massachusetts, have been studying one rare animal, the North Atlantic right whale. For more than two decades, New England Aquarium researchers have been scooping up whale poop and assessing the hormone levels contained inside the cinnamon-colored excrement. The hormones provide information about an animal’s sexual maturity, metabolism, and stress. This information is critical to determining the right whales chance of survival. It is doomed to extinction unless new individuals are born and successfully reach maturity and breed. Without calves there will be no new animals to replenish the dwindling population.  

Saving these endangered creatures

Recovery plans must be developed in order to protect rare creatures from extinction. These plans need to identify ways to mitigate unnatural deaths and promote successful births. Both are critical in the prevention of further declines in population number. Ultimately, the goal is to decrease the chances of extinction. In the case of the North Atlantic right whale, the work of the New England Aquarium is imperative as only about 335 animals are left. Currently, “there are more deaths than there are births. So knowing that there’s potentially another calf on the horizon to add to this population is absolutely crucial,” said Liz Burgess, one of the New England Aquarium scientists who study the right whale. To survive right whale calves must survive a gauntlet of obstacles – boat strikes, rope entanglement, pollution – to reach maturity and it isn’t until it successfully rears its own offspring that there is a ray of hope. 

The narwhal 

The existence of a sea unicorn, more widely known as the narwhal, has been documented. The life history of the narwhal is not well known because it lives in the extreme icy conditions of the Arctic. At present, the narwhal is not designated as an endangered species but it is considered “near threatened” by the International Union for Conservation of Nature. Tens of thousands of narwhals are estimated to inhabit the Northern Hemisphere polar seas.  

One of the narwhal’s most defining features is a spiraled tusk that grows upwards of 9 feet in length. The long projection from the head is a tooth in the upper jaw rather than a horn on the forehead. The name narwhal has been reported to have Norse roots that mean whale corpse allegedly based on the look of their mottled skin which resembles a drowned human.  

What we know about the narwhal is thanks to the efforts of hardy people who live and work in the extreme conditions of the far north. Indigenous people of these northern clines have long studied the narwhal as they have relied on the marine mammal as a food source. Some academic researchers have relied on the assistance of these hunters to get approach narwhals close enough  to obtain high-quality recordings and observe whale behavior. With limited access, researchers still have many questions about narwhals and little answers. “If we want to start being able to answer these questions, it’s important to understand what their acoustic signals ae telling us. That’s how these supervised observations help us approach the more long-term questions we have about these still not-well-understood animals,” said Evgeny Podolskiy, a geophysicist who studies narwhals. Researchers have used a range of underwater sensors to study whale communication as well as water salinity, temperature and more.  

High-resolution satellite images is a technique for scientists “to eavesdrop on conditions where narwhals are comfortable, all from somewhere more comfortable for the researchers.” If an individual can be captured and outfitted with an electronic tag, it may be tracked for upwards of a year revealing information about its movements. As with any activity that involves interaction with humans, tagging causes stress. As one study indicated “narwhals respond to stress with one of the most extreme fright responses ever recorded. The narwhal’s drastic physiological response and time spent out of homeostasis may have negative effects on their health.”  

At the present time, the narwhal population as a whole does not appear to be under significant threat; however, their future is not assured. Sea ice in the Arctic is disappearing at an alarming rate due to climate change. The consequences of the loss of sea ice are many. Among them is the possibility that the narwhals’ preferred food may dwindle in availability and there will be increased predation on them by killer whales. The loss of Arctic ice may result in increased human intrusion in the area from oil and gas exploration and extraction, shipping traffic, and commercial fishing. The consequences of human activity include accelerated chances of narwhals being involved in boat strikes and declining health and well-being due to oil and noise pollution and entanglement with fishing gear. The disappearance of sea ice may increase the chances that scientists have increased opportunities to study both living and deceased narwhals, but to what cost? If the situation becomes dire, the existence of this genuine marine unicorn may someday be little more than an anecdote in a science textbook or a Wikipedia entry.

portions of this article were published on earth.org