Narwhal Tusks – Arctic Swiss Army Knives Used for Hunting and More
New research highlights the versatile functions of the narwhal’s tusk, revealing its surprising role in hunting and beyond.
The narwhal tusk, a remarkable feature of the Arctic “unicorn,” has long captivated scientists and nature enthusiasts. The functions of this spiraled, elongated tooth, primarily found in males and growing up to 3 meters long, have puzzled scientists for a long time, especially since around 15 percent of females are equipped with it as well. But it is now understood to be more than just a display of virility.A new study published in Frontiers in Marine Science demonstrates that the tusk serves as a surprisingly versatile tool, akin to a “Swiss Army Knife,” for these elusive marine mammals, particularly in hunting.
Groundbreaking drone footage has provided the first detailed observations of narwhals skillfully employing their tusks to capture Arctic char. Researchers from Florida Atlantic University’s Harbor Branch Oceanographic Institute, in collaboration with Fisheries and Oceans Canada, the University of Windsor, and other Canadian research institutions, worked with Inuit communities in Nunavut to document this behavior.
Published on February 28, 2025, the study reveals the “remarkable dexterity, precision and speed of movement of the tusk” exhibited by narwhals during prey interactions. Scientists observed narwhals using the tips of their tusks to “interrogate and manipulate” Arctic char, with brief tusk contacts often eliciting a response from the fish. In some cases, the force applied with the tusk was “sufficient… to stun and possibly kill the fish” before consumption, as stated in the scientific publication.
This research, as highlighted in the Frontiers in Marine Science article, offers “new insight into tusk use, the tactics used in the targeting and tracking of potential prey, social behavior, and the first reports of attempted kleptoparasitism on narwhals.” The team cataloged 17 distinct behaviors, showcasing the intricate dynamics between narwhals, their prey, and even opportunistic glaucous gulls attempting to steal a meal.
While the study emphasizes the tusk’s hunting capabilities, it also noted narwhals using their tusks for exploration and playful interactions with their environment, suggesting a broader range of functions beyond what was previously recognized.
Arctic Char: An Unexpected Prey
Interestingly, while narwhals are known to primarily feed on Greenland halibut, polar cod, and squid, this study focused on observations of them hunting Arctic char. Although not considered a staple prey, Arctic char are seasonally available and represent an important food source. Notably, Fisheries and Oceans Canada had already documented similar tusk-assisted hunting behaviors in 2017, further supporting the idea that this tactic is not entirely novel but perhaps under-documented until now.
A Sensory “Swiss Army Knife”
Adding another layer of complexity, the narwhal tusk functions not only as a physical tool but also as a sophisticated sensory organ. Research from Harvard Medical School has revealed that the tusk is densely innervated with millions of nerve endings and has a porous structure, enabling it to detect subtle changes in water salinity. This sensory capability might aid narwhals in navigating their icy habitat and locating prey in the often murky Arctic waters. According to Dr. Martin Nweeia, a leading narwhal tusk researcher, the tusk is “the first tooth that has been shown by in vivo testing to have sensory function to a normal variable in its environment.”
Implications for Narwhal Survival
Understanding the multifaceted role of the narwhal tusk, especially its newly revealed hunting function, is increasingly important in the context of a rapidly changing Arctic. As climate change alters prey distributions and ice conditions, the “Swiss Army Knife” tusk and the adaptability it provides may be crucial for the narwhal’s continued survival in this dynamic environment.
For communities across the Arctic, narwhals are culturally and ecologically significant, playing a vital role in the delicate balance of the polar environment. As the Arctic faces environmental changes, including shifting conditions and increasing human activities, insights gained from this kind of collaborative research become increasingly valuable. Moreover, the discovery of tusk-assisted hunting raises new questions, particularly: how do the narwhals, especially females and tuskless males, successfully navigate the Arctic Ocean and finding their prey without this prominent tool? After all, about 85 percent of all female narwhal are tuskless.
The researchers are certain that non-invasive technologies like drones are proving invaluable in gathering such data, thereby allowing them to gain deeper insights into these enigmatic “unicorns of the sea” and contribute to their conservation in a warming Arctic.
Michael Wenger, Polar Journal AG
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