4 Threats to Narwhals
Whales are a living memory of prehistoric times, when giants walked on Earth and swam in the oceans. These days, many of them are under threat. And, specifically, the threats to narwhals represent an impending disaster, not only for them, but also worldwide.
Narwhals, which in the 16th century terrorized ships on expeditions to the Arctic, are now victims of their great specialization and climate change. We’re now going to get to know this situation in a little more depth.
Characteristics of narwhals
The narwhal (Monodon monoceros) is an odontocete cetacean —that is, one that has teeth. It belongs to the Monodontidae family, which consists only of them and the belugas (Delphinapterus leucas). It inhabits the waters of the Arctic and the North Atlantic.
The most striking feature of this species is the long helical tusk that the males have, which can measure up to 2 meters (over 6 feet) in length. Without this tusk, its body length is around 4.5 meters (nearly 15 feet) and an adult specimen weighs between 1 and 1.5 tons. Experts highlight its usefulness in guiding the ultrasounds of echolocation.
At first, it was thought that narwhal’s tusks were useful for making holes in the thick ice sheets of the Arctic. However, there are other hypotheses that we can’t rule out. One is that they use them to impress females, and they also may have other sexual uses. Without a doubt, there’s still a lot we need to find out about this aquatic mammal!
Narwhals feed on fish and crustaceans from the seabed, where they dive for a maximum of half an hour and at a depth of 800 meters (over 2600 feet). The species they consume are select ones: cod, herring, halibut, flounder and salmon. They usually head to the coasts in winter and go out to sea during the summer.
They’re gregarious animals that live in groups of 5 to 10 individuals, but in summer hundreds of them can congregate. They have a wide variety of vocalizations, including echolocation clicks and different whistles, which they modulate in order to recognize each other.
When narwhals approach a place of interest, they communicate this to their peers as if it were the proximity sensor of a car. They increase the frequency of clicks, until it becomes almost a continuous hiss.
Are killer whales one of the threats to narwhals?
Orcas, or killer whales, (Orcinus orca) are the most widely distributed cetaceans in the world’s oceans. However, they don’t go too far into the Arctic areas, because under the thick layers of ice they could get lost and drowned, or lose their dorsal fin. However, with the thaw caused by climate change, they have seen their opportunity to search for new prey.
A new study found that a population of between 136 and 190 killer whales spent the warmest summer months in the northern region of Baffin Island, Canada. Between 2009 and 2018, orcas fed on up to 1,500 narwhals each season. These predators, because they hunt cooperatively, are capable of killing animals as large as narwhals.
At present, these cetaceans don’t count as one of the true threats to narwhals, at least in the short term. However, experts say that we should keep monitoring this situation. As the thaw progresses, the killer whales could move further and further north.
Threats due to global warming
Everyone knows that the Arctic is thawing. However, the consequences of this are so numerous and affect things at so many levels that it’s difficult to truly conceive what’s happening. These are some of them:
- The Arctic, as such, could disappear: Unlike Antarctica, which has a land area, the Arctic is a gigantic piece of ice floating in the sea.
- The thaw is producing a progressive rise in sea levels, which threatens to reduce the surface of the continents drastically.
- The change in ocean temperatures is altering the marine and atmospheric currents. This results in anomalous weather events across the planet.
- The emission of greenhouse gases accumulated in permafrost is also a threat.
- The reappearance of diseases: The thawing of a reindeer carcass in 2016 led to the reappearance of anthrax.
- A warmer climate has implications at all levels of the food network. The first species to be affected will be the algae that live under the sea ice and are an important part of the diet of many species that inhabit the Arctic.
Narwhals are highly affected by these changes, as their ability to adapt is limited. They’re highly specialized in their habitat. You’ll now learn how climate change is altering their lives.
1. Habitat loss is one of the biggest threats to narwhals
The less ice, the less habitable surface for these mammals. Their forays under the dense ice sheet seem to be the strategy to flee from predators and human threats. As a result, the less ice there is, the more exposed they are to threats.
2. Human activity
The diminishing ice has exposed oil fields, which attracted prospectors and entrepreneurs. On the other hand, the fishing industry is increasingly entering the territory of narwhals and other marine animals, affecting the waters and depriving them of their food.
The noise of the sonar from the boats interferes with the echolocation of the cetaceans in the area. On the other hand, many narwhals get caught in fishing nets or die when they collide with boats’ propellers.
3. Changes in the ice sheet
Alterations in temperatures change the pattern of the ice’s surface. Narwhals usually locate the areas where they can come to the surface to breathe. However, in the face of these alterations, there are more cases of these cetaceans getting trapped under layers of ice that weren’t there before and drowning.
As you can see, threats to narwhals, which, in turn, also affect other cetaceans, are one of the great concerns for environmental organizations, as well as a large part of the human population. However, to put pressure on the organisms responsible for the protection of the environment we don’t only need to think of them – we humans are also suffering the consequences of the thaw.
Never before seen snowfalls, droughts, fires that last for months. This is all extremely unusual and most people know that something has gone wrong with the Earth’s climate in recent years. Far from being able to continue admiring the wonders of nature, solving climate change is becoming a matter of mere survival.It might interest you...
All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.
- Sentry, O. (2010, 8 septiembre). El cambio climático amenaza a los narvales. Ocean Sentry. https://www.oceansentry.org/es/el-cambio-climatico-amenaza-a-los-narvales/
- 2020). Soundscape of a narwhal summering ground in a glacier fjord (Inglefield Bredning, Greenland). Journal of Geophysical Research: Oceans, 125, e2020JC016116. https://doi.org/10.1029/2020JC016116 , & (
- Lowry, L., Laidre, K. & Reeves, R. 2017. Monodon monoceros. The IUCN Red List of Threatened Species 2017: e.T13704A50367651. https://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T13704A50367651.en. Downloaded on 15 June 2021.
- Killer whale abundance and predicted narwhal consumption in the Canadian Arctic. Glob Change Biol. 2020; 26: 4276– 4283. https://doi.org/10.1111/gcb.15152 , , .
- Whale and Dolphin Conservation Society. (2007). Whales in hot water http://awsassets.panda.org/downloads/climatechange16ppfinallo.pdf