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Post by grrraaahhh on Mar 22, 2010 18:41:10 GMT -9
Yes, polar bears DO predate adult walruses. INTERACTIONS BETWEEN POLAR BEARS AND OVERWINTERING WALRUSES IN THE CENTRAL CANADIAN HIGH ARCTIC WENDY CALVERT, Canadian Wildlife Service, 5320 122 Street, Edmonton, AB T6H 3S5 IAN STIRLING, Canadian Wildlife Service, 5320 122 Street, Edmonton, AB T6H 3S5 and Department of Zoology, University of Alberta, Edmonton, AB T6G 2E9 Abstract: There are few records of predation by polar bears (Ursus maritimus) on walruses (Odobenus rosmarus), although their distributions overlap extensively. During the late winter and early spring from 1981 through 1989, we recorded interactions between polar bears and walruses in the central Canadian High Arctic, where walrus movements are severely restricted in the winter by limited areas of open water for breathing and haulout holes. Predatory behavior of bears and anti-predator behavior of walruses were observed. We found evidence that polar bears made wounding but non-fatal attacks on 3 walruses, killed 3 walruses, and probably killed 4 others. One\ walrus was frozen out of its breathing hole and vulnerable to predation. Although the vulnerability of walruses to polar bear predation would vary with habitats and seasons, it is clear that polar bears are important predators of walruses in the central Canadian High Arctic in late winter-early spring. PDF LINK: www.bearbiology.com/fileadmin/tpl/Downloads/URSUS/Vol_8/Calvert_Stirling_8.pdf
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Post by grrraaahhh on Jul 13, 2010 13:34:18 GMT -9
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Post by apollyon on Aug 2, 2010 18:18:37 GMT -9
"Polar bears, Ursus rnaritirnus, are large, powerful predators that sometimes attack and kill species such as the walrus, Odobenus rosrnarus (KiliaanandS tirling, 1978a)n d the bearded seal, Erignathus barbatus (Stirling and Archibald, 1977; Smith, 1980), which can be heavier and larger than themselves."
It definitely says they can kill Walrus larger than themselves but does this necessarily mean adult Bulls?
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Post by grrraaahhh on Aug 2, 2010 19:29:28 GMT -9
I edited the OP. I posted a different article by mistake. Thanks for the catch.
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Post by grrraaahhh on Jan 25, 2011 23:25:05 GMT -9
Walruses that overwinter in an area with restricted access to water become potentially vulnerable to predation by polar bears. Three observations support this. On 19 April 1976 one of us (HPLK) found two walruses that apparently had been killed by polar bears. One was an adult female 22+ years old (289 cm long, estimated weight 400+ kg). There was blood on top of her frozen over haul-out hole, indicating that she might have been frozen out when the bear attacked. The other walrus (unsexed) was just under 2 years old (243 cm long, estimated weight 270 kg). A blood trail indicated that it had been captured beside or in a 60 cm wide channel that went around the circumference of a 25 to 30 m diameter grounded iceberg.
Examination showed that both walruses had large numbers of sharp deep punctures about their heads which could only have been made by bear claws, suggesting that they may have been killed by multiple blows. Soper (1928) quotes a report by Hantzch of a large bear in the vicinity of Kikerten Islands, Cumberland Gulf, attacking three walruses and killing a large male which it tore extensively about the head. Akpaleeapik, a Grise Fiord Eskimo, also informed us of a walrus that a polar bear killed with a blow in the head as it surfaced to breathe through a hole in the ice. On 29 April 1976 Mr. Tai-Ho of Klondike Helicopters tracked a polar bear to a walrus that he estimated to be less than 3 m long with tusks 20 to 25 cm long. Tracks and blood in the snow around the walrus's breathing hole (1 to 1.5 m diameter) indicated a fight had taken place very recently. The walrus was covered with blood and one tusk was broken. Despite a careful search, no bear tracks leading away from the site were found, suggesting that the bear may have been killed and sunk in the water. Freuchen (1935) reported finding a polar bear that had been killed by a walrus, and Perry (1966) summarizes similar observations from the journals of early arctic explorers. Although predation by bears is likely not of any significance to the walrus population as a whole (Mansfield, 1958; Loughrey, 1959) such encounters may be more frequent than previously seemed apparent.
H. P. L. Kiliaan and Ian Stirling, Observations on Overwintering Walruses in the Eastern Canadian High Arctic. Journal of Mammalogy Vol. 59, No. 1 (Feb., 1978), pp. 197-200.
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Post by grrraaahhh on Feb 17, 2011 22:20:55 GMT -9
Sometimes, polar bears are killed in confrontations with walruses:
The polar bear and walrus, traditional rivals, occasionally come in contact while feeding on whale carcasses or while killing seals. If a walrus is in the water, a polar bear will not enter. The walrus is the only polar animal that the bear really fears.
Reaching fifteen feet in length and weighing as much as one and a half tons, the walrus is more than a formidable adversary. If the two animals encounter each other on land, the polar bear will have an edge. When they meet each other in the water, the walrus has been known to grab the polar bear from below and, using his ivory tusks, which often grow more than thirty inches in length, to stab the bear in the back, driving the tusks to the hilt. The carcasses of polar bears and walruses have been found coupled in this manner.
Koch, T.J. 1975 The Year of the Polar Bear p. 81.
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Post by grrraaahhh on Feb 25, 2011 9:45:21 GMT -9
Walrus death resulting from Polar bears manifest in various forms:
We observed that several carcasses had been scavenged by bears; however, it is unknown whether the bears disturbed live walrus herds and caused the death of some walruses from trampling, as has been observed at Russian Chukchi Sea coastal haulouts (Kochnev, 1999, 2006; Kavry and others 2006, Ovsyanikov and others 2008), or were drawn to carcasses to scavenge.
Fischbach, A.S., D.H. Monson, and C.V. Jay. 2009. Enumeration of Pacific walrus carcasses on beaches of the Chukchi Sea in Alaska following a mortality event, September 2009. U.S. Geological Survey Open-File Report 2009-1291:10.
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Post by Deleted on Jul 2, 2011 22:20:49 GMT -9
"Polar bears, Ursus rnaritirnus, are large, powerful predators that sometimes attack and kill species such as the walrus, Odobenus rosrnarus (KiliaanandS tirling, 1978a)n d the bearded seal, Erignathus barbatus (Stirling and Archibald, 1977; Smith, 1980), which can be heavier and larger than themselves." It definitely says they can kill Walrus larger than themselves but does this necessarily mean adult Bulls? Acctually i posted an article which says a polar bear is capable of killing an adult bull on on one yet prefers calves because walrus bulls are often around other bulls and hard to kill because of their thick skin which makes it hard to pierce their jagular vain. Calves take a shrother time to kill
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Post by Deleted on Jul 3, 2011 13:42:17 GMT -9
Annother account of polar bear predation on walrus.From walruses we pass to bears. Mr.Lamont believes that the Polar Bear - the Ursus Maritimus of naturalists - is, in a state of nature, the largest and strongest carnivorous animal in the world. Be this as it may, his first specimen - the one which he was watching through the old opera-glass of which we have spoken - was a monster. His carcass measured eight feet in length, and almost as much in circumference. He stood four and a half feet high at the shoulder. The fore-paws were 34 inches around. His weight was at least 1200 pounds: of this the fat constituted 400 pounds, and the hide 100. When skinned, his neck and shoulders were like those of a bull. The hunters say that he will kill the biggest bull-walrus, although nearly three times his own weight, by springing upon him from behind, and battering in his skull by repeated blows. Mr. Lamont believes this, though he doubts the stories told of the way in which he is killed by hunters. One man, who professes to know all about it, says that the hunters use a spear having a cross-piece a couple of feet from the point. Hunter presents point to Ursus; Ursus seizes spear by cross-piece, and in trying to drag it away buries the blade in his own body, and so kills himself. And this: Stout as he is, Ursa maritimus has to use cunning to get a living. He relies mainly upon walruses and seals. Though quite competent to manage the biggest walrus singly, he is overmatched by a herd; and unluckily for him walruses are apt to go in herds. He can not pick up a "junger" without bringing down upon him a score of tusked cousins and uncles. Then the seals are so shrewd. In the water they do not fear him. They can outswim and outdive him. There they will play around him in a manner calculated to aggravate his feelings to the utmost. Mr. Lamont thinks he catches one in the water now and then, but he can not con- ceive how he does it. Upon the ice Ursa has the advantage. But the seals know this, and sleep with both ears and one eye open. But Ursa's eyes and nose are of the sharpest. When either of these tell him that seals are floating about on the ice he slips into the water, half a mile or so to the leeward, and paddles quietly along, with his nose only visible, until he is close under the cake of ice on the very edge of which the seal is reposing. Then one jump, and a blow of his huge paw, settles the business. Between strength and cunning Ursa manages to make a quite comfortable living, and keep himself in very good order. Three which Mr. Lamont killed yielded 600 pounds of fat. "What a thousand pities," he exclaims, "that it is not worth 3s. 6d. a pot, as in the Burlington Arcade!" www.explorenorth.com/library/weekly/aa032201c.htm
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Post by grrraaahhh on Jul 3, 2011 20:00:17 GMT -9
Annother account of polar bear predation on walrus.From walruses we pass to bears. Mr.Lamont believes that the Polar Bear - the Ursus Maritimus of naturalists - is, in a state of nature, the largest and strongest carnivorous animal in the world. Be this as it may, his first specimen - the one which he was watching through the old opera-glass of which we have spoken - was a monster. His carcass measured eight feet in length, and almost as much in circumference. He stood four and a half feet high at the shoulder. The fore-paws were 34 inches around. His weight was at least 1200 pounds: of this the fat constituted 400 pounds, and the hide 100. When skinned, his neck and shoulders were like those of a bull. The hunters say that he will kill the biggest bull-walrus, although nearly three times his own weight, by springing upon him from behind, and battering in his skull by repeated blows. Mr. Lamont believes this, though he doubts the stories told of the way in which he is killed by hunters. One man, who professes to know all about it, says that the hunters use a spear having a cross-piece a couple of feet from the point. Hunter presents point to Ursus; Ursus seizes spear by cross-piece, and in trying to drag it away buries the blade in his own body, and so kills himself. And this: Stout as he is, Ursa maritimus has to use cunning to get a living. He relies mainly upon walruses and seals. Though quite competent to manage the biggest walrus singly, he is overmatched by a herd; and unluckily for him walruses are apt to go in herds. He can not pick up a "junger" without bringing down upon him a score of tusked cousins and uncles. Then the seals are so shrewd. In the water they do not fear him. They can outswim and outdive him. There they will play around him in a manner calculated to aggravate his feelings to the utmost. Mr. Lamont thinks he catches one in the water now and then, but he can not con- ceive how he does it. Upon the ice Ursa has the advantage. But the seals know this, and sleep with both ears and one eye open. But Ursa's eyes and nose are of the sharpest. When either of these tell him that seals are floating about on the ice he slips into the water, half a mile or so to the leeward, and paddles quietly along, with his nose only visible, until he is close under the cake of ice on the very edge of which the seal is reposing. Then one jump, and a blow of his huge paw, settles the business. Between strength and cunning Ursa manages to make a quite comfortable living, and keep himself in very good order. Three which Mr. Lamont killed yielded 600 pounds of fat. "What a thousand pities," he exclaims, "that it is not worth 3s. 6d. a pot, as in the Burlington Arcade!" www.explorenorth.com/library/weekly/aa032201c.htm Nice to have a polar bear fan in our company. I've read this account before. In this case, biologist observations confirm earlier hunter polar bear/walrus accounts. FYI, the only necessary link to provide are primary source ones. Thanks.
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Post by grrraaahhh on Aug 25, 2011 14:07:52 GMT -9
An adult walrus is not easy prey even for the mighty polar bear. © Nikita Ovsayanikov
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Post by Deleted on Aug 25, 2011 19:59:45 GMT -9
I haven't seen this picture in a while. The walrus is definately not easy prey because of its thick skin and its neck and blubber plus those tusks. Again the polar bear in the picture seems to be looking for an opening to attack the walrus.
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Post by grrraaahhh on Aug 26, 2011 3:20:40 GMT -9
I haven't seen this picture in a while. The walrus is definately not easy prey because of its thick skin and its neck and blubber plus those tusks. Again the polar bear in the picture seems to be looking for an opening to attack the walrus. The location is Wrangel Island, off the Russian Arctic coast.
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Post by grrraaahhh on Aug 27, 2011 12:01:28 GMT -9
I haven't seen this picture in a while. The walrus is definately not easy prey because of its thick skin and its neck and blubber plus those tusks. Again the polar bear in the picture seems to be looking for an opening to attack the walrus. The location is Wrangel Island, off the Russian Arctic coast. POLAR BEAR PREDATION UPON WALRUSES OF WRANGEL ISLAND (OVSYNIKOV N.G.) Taking a look at relating Russian literature (above); the article confirms during the observed time period no successful predation of adult walrus who as a group were able to fight off the threat from hungry male polar bears (picture a wall of giant slashing tusks aggressively slashing away) by retreating to the safety of the sea. The author explains that adult walrus fear adult male polar bears but as we understand it (personal observation not the authors) successful predation of adult walrus by polar bears for many reasons is difficult. There are however relating documentary video from the Education & Video section (Siberian Polar Bear) one from the Wild Russia NG series and the other shorter clip from the Ultimate Bear documentary: There are other relating Russian literature to examine. Stay tuned....
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Post by Deleted on Aug 28, 2011 18:56:45 GMT -9
Great videos, it does show that polar bears are capable of taking on adult walruses one on one even though that adult killed was probably sick.
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