Walruses, those magnificent giants of the Arctic seas, are instantly recognizable by one extraordinary feature: their prominent, lengthy tusks. These are not mere dental decorations or oversized teeth for show. Instead, walrus tusks are sophisticated, multi-functional tools, absolutely essential for nearly every aspect of the animal’s existence, from navigating its icy world to intricate social signalling. To truly appreciate the walrus, one must understand the profound importance of these impressive ivory structures, which extend far beyond simple biting or chewing.
The Anatomy of a Tusk
At their core, walrus tusks are massively elongated canine teeth. They are a defining characteristic of both male and female walruses, though in adult males, the tusks tend to be noticeably longer, thicker, and often straighter compared to those of females. One of the most fascinating aspects of these tusks is their continuous growth throughout the walrus’s lifespan. In older, larger bulls, these tusks can achieve truly impressive lengths, sometimes extending up to a meter, or just over three feet, from the upper jaw.
Unlike the enamel-covered teeth found in many other mammals, walrus tusks are primarily constructed from a dense, ivory-like material called dentine. This dentine is then covered by an outer layer of cementum, rather than enamel. Deep within the tusk lies a pulp cavity, containing nerves and blood vessels, much like other mammalian teeth. This persistent growth is crucial, as it helps to compensate for the significant wear and abrasion the tusks endure from their constant and varied use in the challenging Arctic environment.
A Multi-Tool for Arctic Life
The tusks of a walrus serve an astonishing array of purposes, making them indispensable for survival and social interaction.
Social Standing and Communication
Within walrus society, tusks are significant symbols. The size, symmetry, and overall condition of a walrus’s tusks often serve as visual cues, broadcasting information about its age, general health, and, crucially, its social status within the herd. Generally, individuals, especially males, possessing larger, more formidable, and unbroken tusks command greater respect and occupy higher positions in the social hierarchy. This is particularly evident during the breeding season when males compete for access to females.
These impressive dental appendages are frequently employed in displays of dominance or aggression. Walruses will rear up out of the water or on land, prominently showcasing their tusks to rivals. While actual physical combat involving tusk-clashing does occur, these confrontations are often highly ritualized. The primary goal is usually to establish or reinforce dominance hierarchies, rather than to inflict severe or fatal injuries, although wounds can certainly be sustained during such encounters.
The “Tooth-Walker’s” Ascent
The scientific name bestowed upon the walrus, Odobenus rosmarus, is wonderfully descriptive, translating from Greek and Latin roots to mean “tooth-walker.” This moniker directly references one of the most vital functions of their tusks: locomotion. Walruses use their tusks much like a mountaineer uses ice axes or grappling hooks. They expertly dig the tips of their tusks into slippery ice floes or rugged, rocky coastlines to gain purchase and haul their immense, blubbery bodies out of the frigid Arctic waters. Some individuals can weigh up to 2,000 kilograms (around 4,400 pounds).
This ability to “haul out” is absolutely critical for their survival. Walruses are not fully aquatic and must come ashore or onto ice to rest, to molt their skin, to give birth, and for females to nurse their dependent calves. Without the leverage and grip provided by their tusks, performing this essential maneuver, especially on slick, unstable ice surfaces, would be incredibly arduous, if not entirely impossible, for such massive creatures.
Foraging in the Deep
For many years, the prevailing belief was that walruses primarily utilized their tusks as rakes, dragging them along the seabed to stir up and dislodge the clams, mussels, snails, and other benthic invertebrates that constitute the mainstay of their diet. While tusks might occasionally be employed in this fashion, or to clear away larger obstacles, more recent and detailed observations have painted a more complex and nuanced picture of their foraging techniques.
Many marine biologists now posit that walruses predominantly rely on their highly sensitive mystacial vibrissae (the dense mat of whiskers on their snout) and their powerful, muscular lips and snouts to locate and unearth prey buried in the soft sediment. Once located, they are thought to use strong oral suction to extract the soft bodies of mollusks from their shells. Tusks might play a secondary role, perhaps helping to anchor the walrus against strong currents while it feeds, or possibly being used to dispatch larger, less common prey items. The precise and varied roles of tusks in direct food acquisition remains an active area of scientific investigation.
Defense Against Predators
While the sheer bulk and thick, tough hide of a walrus offer a substantial degree of natural protection, their tusks provide a truly formidable means of active defense. When faced with threats from natural predators such as polar bears on the ice or pods of orcas (killer whales) in the water, a group of walruses can present a daunting and dangerous barricade of sharpened ivory. A determined thrust or a powerful swing from a tusk-wielding walrus can inflict grievous, potentially lethal, injuries upon an attacker, making predators think twice before engaging.
Maintaining Access to Air
In Arctic regions where sea ice can become extensively thick and unbroken, walruses have been documented using their robust tusks as tools to create or maintain breathing holes. By chipping and levering at the ice, they can ensure access to the surface for air, even when foraging in areas far from naturally occurring leads or open water. This capability expands their potential foraging grounds and reduces the need for long underwater transits simply to breathe.
Walrus tusks are an extraordinary example of evolutionary adaptation. These elongated canine teeth are composed mainly of dentine and grow continuously throughout the animal’s life. This constant growth is vital, allowing the tusks to withstand significant wear and tear from their diverse uses in the harsh Arctic environment, showcasing nature’s ingenuity in equipping species for survival.
When Tusks are Damaged
Given the rigorous and constant use to which they are subjected, it is not uncommon for walrus tusks to become damaged, worn down unevenly, or even broken. Such injuries can occur during aggressive interactions with other walruses, in accidents while hauling out onto ice or rugged terrain, or potentially while foraging among rocks or hard substrates. The consequences of a significantly damaged or lost tusk can be quite serious for the individual walrus.
A broken or missing tusk can negatively impact a walrus’s ability to establish or maintain its position in the social hierarchy, potentially leading to a lower rank and reduced breeding opportunities, particularly for males. Furthermore, severe tusk damage might compromise their efficiency in hauling out onto essential resting platforms or diminish their capacity to defend themselves effectively against predators. While walruses can certainly survive with one tusk or even with both tusks broken, such conditions undoubtedly render their challenging lives even more difficult.
Tusks and Human History
Walrus ivory, the dense dentine material of their tusks, has been a highly valued resource for Arctic indigenous peoples for millennia. For cultures such as the Inuit, Yupik, and Chukchi, walrus ivory was traditionally and skillfully carved into a wide array of essential tools, including harpoon heads, toggles, ulu handles, and sled runners. It was also used for creating intricate artwork, personal adornments, and items of spiritual or cultural significance. These historical uses were generally part of a subsistence lifestyle and were often conducted in a manner that was sustainable within the context of their populations and environment.
The dynamic shifted dramatically with the arrival of commercial hunters from Europe and North America, starting primarily in the 18th and 19th centuries. These hunters sought walruses mainly for their blubber, which was rendered into oil, and for their tusks, which entered the global ivory trade. This period of intensive, unregulated commercial exploitation led to catastrophic declines in many walrus populations across their range. While large-scale commercial hunting of walruses is now largely prohibited by international agreements and national laws, the legacy of this era serves as a stark reminder of the vulnerability of these remarkable animals when subjected to unsustainable pressures.
A Future Tied to Ice
In the contemporary world, the most pervasive and significant threat facing walrus populations is not direct hunting, but the profound impacts of global climate change, particularly the rapid and ongoing loss of Arctic sea ice. Sea ice is not merely a feature of their environment; it is a critical platform for nearly all essential life activities of the walrus. They rely on it for resting between foraging trips, for giving birth and nursing their calves in relative safety, and as a stable base from which to access their preferred shallow-water feeding grounds. Their tusks, so perfectly adapted for hauling out onto ice, underscore this deep dependency.
As seasonal sea ice diminishes in extent, thickness, and duration, walruses are increasingly forced to haul out on terrestrial coastal sites. These land-based haulouts often result in extremely large, dense congregations of animals, sometimes numbering in the tens of thousands. Such conditions can lead to increased stress, greater risk of disease transmission, and dangerous stampedes, which can be fatal, especially for younger, smaller walruses. Understanding the multifaceted roles of their tusks – these incredible tools for ice-walking, defense, and social display – truly highlights how deeply intertwined walrus physiology, behavior, and survival are with their traditionally icy habitat. The impressive canines that so strikingly define them are a powerful testament to their evolutionary adaptation to an Arctic world that is now undergoing unprecedented and rapid transformation. They are, indeed, far more than just impressive teeth; they are fundamental keys to survival in one of the planet’s most demanding and changing ecosystems.
