Narwhal v Walrus

[Deleted]

Narwhal - Monodon monoceros


The narwhal, or narwhale, Monodon monoceros, is a medium-sized toothed whale that lives year-round in the Arctic. One of two living species of whale in the Monodontidae family, along with the beluga whale, narwhal males are distinguished by a long, straight, helical tusk, actually an elongated upper left canine. Found primarily in Canadian Arctic and Greenlandic waters, rarely south of 65°N latitude, the narwhal is a uniquely specialized Arctic predator. In the winter, it feeds on benthic prey, mostly flatfish, at depths of up to 1500 m under dense pack ice. These are medium-sized whales, being around the same size as a beluga whale. Total length in both sexes, excluding the "tusk" of the male, can range from 3.95 to 5.5 m (12 ft 12 in to 18 ft 1 in). Males, at an average length of 4.1 m (13 ft 5 in), are slightly larger than females, at an average of 3.5 m (11 ft 6 in). Typical adult body weight can range from 800 to 1,600 kg (1,800 to 3,500 lb). The most conspicuous characteristic of the male narwhal is its single extremely long tusk, a canine tooth[11] that projects from the left side of the upper jaw and forms a left-handed helix. The tusk seems to grow slightly throughout life from 1.5 to 3.1 m (4 ft 11 in to 10 ft 2 in). Despite its formidable appearance, the tusk is hollow and weighs only around 10 kg (22 lb).





Walrus - Odobenus rosmarus

Walruses occupy a nearly circumpolar region of the Arctic. Three distinct subspecific populations are recognized: 1) Atlantic (Odobenus rosmarus rosmarus), which lives in the eastern Canadian Arctic and Greenland east to Novaya Zemlya; 2) Pacific (O. r. divergens), living in the Bering Sea and adjacent Arctic Ocean; 3) Laptev Sea (O. r. laptevi), occupying the Laptev Sea, north of Siberia. Some taxonomists do not recognize the Laptev Sea population as a separate subspecies. Walruses prefer to inhabit areas with ice floes in the shallower regions near the coasts of Arctic waterways. Their seasonal migration patterns coincide with the changes in the ice. In the winter, walruses move south as the Arctic ice expands, and in the summer they retreat north as the ice recedes. This migration can cover distances of 3000 km. Individuals concentrate where the ice is relatively thin and dispersed in the winter. In the summer time, bulls may use isolated coastal beaches and rocky islets. Cows and young prefer to stay on ice floes in all seasons. While some outsized Pacific males can weigh as much as 2,000 kg (4,400 lb), most weigh between 800 and 1,680 kg (1,800 and 3,700 lb). The Atlantic subspecies weighs about 10–20% less than the Pacific subspecies. The Atlantic Walrus also tends to have relatively shorter tusks and somewhat more flattened snout. Females weigh about two-thirds as much, with the Atlantic females averaging 560 kg (1,200 lb), sometimes weighing as little as 400 kg (880 lbs), and the Pacific female averaging 794 kg (1,750 lb). Length ranges from 2.2 to 3.6 m (7.2–12 ft). It is the second largest pinniped, after the elephant seals.

[Vodmeister]

Both have quite similar weapons and and roughly equal in size. Nonetheless, I would give it to the Walrus 6/10, it is bulkier and probably more durable.

[Deleted]

Feb 18, 2014 23:37:36 GMT 5 Vodmeister said:

Both have quite similar weapons and and roughly equal in size. Nonetheless, I would give it to the Walrus 6/10, it is bulkier and probably more durable.

Similar weapons? I think the Narwhal would struggle to effectively use it's weapon, whereas the walrus can easily stab the Narwhal with it's tusks if it avoids that tusk.


I also vote for the Walrus. I don't see the Narwhal being able to effectively use it's weapon before it breaks and has nothing to do other than to either retreat or die.

[Infinity Blade]

Here's what the narwhal's tusk is really used for.

www.npr.org/templates/story/story.php?storyId=5050264
About the Narwhal's "horn":
"NIELSEN: What could the purpose of a tusk like this, Nweeia wanted to know? And so he wrangled a grant and set off for the Canadian Arctic leading a team of scientists and Inuit elders. At the time, some experts thought the narwhal used its tusk to poke holes through thin ice while others thought it used it as a weapon. Nweeia didn't think those theories worked for a tusk that had its soft parts on the outside. That hunch deepened when tests began to show that the pulp surrounding this tusk was extremely sensitive to water pressure, temperature and salinity.

Dr. NWEEIA: You can think of it as a weather station. It has those abilities to detect changes in both its water environment and its air environment. It has--you know, even when it pushes that tusk above the water, it has the capability to understand barometric pressure and temperature, even of the air."

The hyperallometric scaling and large variation in the tusks supports the hypothesis that narwhal tusks are sexually selected (figure 2; electronic supplementary material, figure S1 and table S1). Sexually selected signals used in male–male competition are more likely to exhibit hyperallometry when compared to other sexually selected traits, because the information being signalled is simple: ‘I am bigger than you’ [9]. To convey this message, males exaggerate the size of their signals which facilitate the detection of size discrepancies between individuals, reducing the likelihood of engaging in potentially dangerous fights [9]. Using the tusk as a signal might explain the tusking behaviour observed in male narwhals (figure 1; [4]). Tusking may be a ritualized behaviour used to assess the fighting ability of opponents and avoid potentially costly fights [36]. In this scenario, fully fledged aggression should be rare, because competitors should attempt to settle contests through signalling [37,38].

However, using the tusk purely as a signal does not explain why head scarring and broken tusks occur. Adult male narwhals possess significantly more scars on their heads compared to juvenile males and females [3,4], similar to the scarring found in other cetaceans that are known to fight [39,40]. Similar injury patterns are also common in other animals that possess signals that also function as weapons [36,41,42]. Additionally, 40–60% of adult males have damaged or broken tusks [2,4], which should be common if narwhals used their tusks in fights [43]. Interestingly, tusks cannot withstand ‘ramming’ forces, which suggest that the tusk is not used for direct stabs [44,45]. However, tusks can withstand lateral strikes without breaking, which might explain the head scarring [44,45]. Considering that the tusk length scaling reaches an asymptote, then tusk length may be constrained by breaking when becoming too long [46] or there are large metabolic costs incurred when individuals produce and maintain massive tusks (but see [47]). Indeed, biomechanical limits to the size and elaboration of sexually selected traits are common [48–50]. Thus, when combing our results of tusk hyperallometry with the known material properties of narwhal tusks, it suggests that the tusk is likely used as an aggressive signal during contests.

Graham et al., 2020

A single, long, straight tusk is almost uniquely ill-suited for establishing male dominance by fighting, because it will be very difficult to engage in any combat that is not entirely ritualized without one or both parties being severely, possibly mortally, wounded. Scars on large males are fairly common, but are nearly always superficial, and are concentrated on the head region, and could easily be caused by encounters with ice or rock. Gerson & Hickie (1985) found that about 2/3 of mature males had broken tusk tips, and reported a few males in which tusk tips were embedded in their jaws. Jurgensen, quoted in Arvy (1978), reported 107 broken tusks in 314 males, a considerably lower fraction than reported by Gerson & Hickie (1985). Whatever agonistic behaviour takes place must be rather ritualized. The above-water tusk clashing that is occasionally seen hardly looks serious.

Brear et al., 1993


So basically, the narwhal's tusk is used for ritualized contests where the males rub and cross their tusks against each other. There's also evidence of it being a sensory organ. Drone footage also exists of narwhals whacking fish to stun them.

There is evidence of a possible aggressive encounter between a male narwhal and a beluga, where the narwhal's tusk tip was embedded in the beluga's melon (Orr & Harwood, 1998). But even then it is impossible to tell whether or not this was an accident (and the beluga clearly survived). Given that the narwhal tusk is evidently unable to withstand ramming impacts and stabbing, I now lean towards this explanation.

So it seems like, at best, the narwhal's tusk is an ineffective weapon far more specialized for ritualized contests. Meanwhile, walruses have been recorded stabbing polar bears. Granted, they don't necessarily kill them, but their tusks are still far better weapons than the narwhal's. Walrus wins.

[Deleted]

The Pinnipeds: Seals, Sea Lions, and Walruses By Marianne Riedman

Taking into consideration of the fact that the narwhal can't use its tusk as a weapon and that walruses prey on narwhals, this probably wouldn't be so much as a fight as it would be a long and drawn out chase/hunt ending in a kill.

[An Goldish Jade]

Narwhals dont even use their tusk to gore, so the Walrus would win this one.

[Deleted]

Exactly, walrus easily wins, and it is stronger.

[dinosauria101]

Yes, I'd favor the walrus as well. It's a lot bulkier, more durable, and if the narwhal's tusk gets broken....well, game over for the narwhal.

[jhg]

Yo, ho, ho a walrrrus takes the win!

[DonaldCengXiongAzuma]

The fight between male walrus is vicious but death is rare as walrus' vital organs are protected by thick skin and blubber. A narwhale might not be as good a fighter but it too has thick skin (like walrus and beluga - skin 100 times thicker than the average land mammal) and blubber to protect their vital organs too. A narwhale is also much larger than a bearded seal.