|
Post by grrraaahhh on Aug 29, 2011 2:01:24 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. Especially when conditions favor the polar bear: " Walruses that overwinter in an area with restricted access to water become potentially vulnerable to predation by polar bears."
|
|
|
Post by sarus on Oct 12, 2011 20:21:11 GMT -9
|
|
|
Post by grrraaahhh on Oct 13, 2011 5:26:49 GMT -9
Great video find...thank you.
|
|
|
Post by Ursus arctos on Feb 19, 2012 11:06:35 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 More from that article: Between 1981 and 1989, we found evidence of 10 walruses that we believe were wounded or killed by polar bears (Fig. 1). The date of death is known only for the kill at site 2 where the bear was observed killing a large adult male walrus and pulling it from its haulout hole (D. Grant, pers. commun.). All the other carcasses were frozen and partially eaten when found. Wind-blown snow often obscured the bear tracks in the area, making it difficult to reconstruct the attack, but the presence of bear claw marks, blood smears, and scratching marks made by walrus flippers indicated an interaction had occurred. In 2 cases, the haulout hole near the carcass was still unfro? zen, suggesting the walruses were killed on the ice before they could escape, and that freezing-out was not a factor. There was blood soaked into the snow beneath the head of the adult male found dead in February 1987 at the shoreline tidal cracks below our camp (site 11), suggest? ing that a bear killed him, though possibly only after the ice shifted and he was frozen out. At 6 of 7 sites of kills or probable kills, polar bears were feeding on the carcass when it was sighted, but we did not know if they were predators or scavengers. Although walruses hit each other on the neck shoulder with their tusks when fighting, they are tected by a thick skin. Most wounds are superficial bleeding is limited. At site 3, there was no carcass, from the tracks we determined a bear had stalked walrus from a distance, using a ridge of rough ice to itself until it was close enough to charge the walrus as it lay by its haulout hole at the edge of a frozen- in multiyear floe. There was blood sprayed on the snow at 3 separate breathing holes around the edge ofthe floe in a pattern that probably resulted from the blood being mixed with expired air from the nostrils. We suspect the bear had time to hit the walrus on the head with a paw, or bite it on the face or nose, before the walrus escaped into the water. The bear's tracks went to all 3 holes, suggesting that it tried unsuccessfully to capture the walrus for some time after the initial attempt, possibly because the wounded animal kept resurfacing at different holes to breathe. We also found unusual amounts of blood that appeared to be from wounding attacks at breathing holes at sites 5 and 9, but it was difficult to interpret what had happened because most of the tracks were covered by drifted snow.
In spring 1976, T. Eley (Alas. Dep. Fish and Game, Fairbanks, unpubl. data) tracked polar bears as part of a study on polar bear predation. He recorded 1 kill of young yearling walrus by a polar bear at Cape Lisburne, Alaska. On 13 June 1987, about 60 km northeast of Point Barrow, Alaska, K. Frost (pers. commun.) observed a adult large male polar bear dragging a medium-sized male walrus, with approximately 25-cm tusks, out ofthe water at the edge of a floe. The walrus was bleeding It had profusely, indicating it had just been killed. apparently been alone at the edge of a floe in an area of broken ice, and was farther east than walruses normally occur in that region.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 16, 2012 16:05:39 GMT -9
|
|
|
Post by warsaw on Dec 22, 2012 4:47:17 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 More from that article: Between 1981 and 1989, we found evidence of 10 walruses that we believe were wounded or killed by polar bears (Fig. 1). The date of death is known only for the kill at site 2 where the bear was observed killing a large adult male walrus and pulling it from its haulout hole (D. Grant, pers. commun.). All the other carcasses were frozen and partially eaten when found. Wind-blown snow often obscured the bear tracks in the area, making it difficult to reconstruct the attack, but the presence of bear claw marks, blood smears, and scratching marks made by walrus flippers indicated an interaction had occurred. In 2 cases, the haulout hole near the carcass was still unfro? zen, suggesting the walruses were killed on the ice before they could escape, and that freezing-out was not a factor. There was blood soaked into the snow beneath the head of the adult male found dead in February 1987 at the shoreline tidal cracks below our camp (site 11), suggest? ing that a bear killed him, though possibly only after the ice shifted and he was frozen out. At 6 of 7 sites of kills or probable kills, polar bears were feeding on the carcass when it was sighted, but we did not know if they were predators or scavengers. Although walruses hit each other on the neck shoulder with their tusks when fighting, they are tected by a thick skin. Most wounds are superficial bleeding is limited. At site 3, there was no carcass, from the tracks we determined a bear had stalked walrus from a distance, using a ridge of rough ice to itself until it was close enough to charge the walrus as it lay by its haulout hole at the edge of a frozen- in multiyear floe. There was blood sprayed on the snow at 3 separate breathing holes around the edge ofthe floe in a pattern that probably resulted from the blood being mixed with expired air from the nostrils. We suspect the bear had time to hit the walrus on the head with a paw, or bite it on the face or nose, before the walrus escaped into the water. The bear's tracks went to all 3 holes, suggesting that it tried unsuccessfully to capture the walrus for some time after the initial attempt, possibly because the wounded animal kept resurfacing at different holes to breathe. We also found unusual amounts of blood that appeared to be from wounding attacks at breathing holes at sites 5 and 9, but it was difficult to interpret what had happened because most of the tracks were covered by drifted snow.
In spring 1976, T. Eley (Alas. Dep. Fish and Game, Fairbanks, unpubl. data) tracked polar bears as part of a study on polar bear predation. He recorded 1 kill of young yearling walrus by a polar bear at Cape Lisburne, Alaska. On 13 June 1987, about 60 km northeast of Point Barrow, Alaska, K. Frost (pers. commun.) observed a adult large male polar bear dragging a medium-sized male walrus, with approximately 25-cm tusks, out ofthe water at the edge of a floe. The walrus was bleeding It had profusely, indicating it had just been killed. apparently been alone at the edge of a floe in an area of broken ice, and was farther east than walruses normally occur in that region. www.bearbiology.com/fileadmin/tpl/Downloads/URSUS/Vol_8/Calvert_Stirling_8.pdf
|
|
kiba
New Member
Posts: 28
|
Post by kiba on Mar 27, 2013 9:59:01 GMT -9
Well, those videos clearly show that polar bears kill both pup and adult walruses biting them in the neck and not with those famous claw swipes we hear from the always unreliable accounts of hunters.
|
|
|
Post by grrraaahhh on Mar 28, 2013 4:48:52 GMT -9
Well, those videos clearly show that polar bears kill both pup and adult walruses biting them in the neck and not with those famous claw swipes we hear from the always unreliable accounts of hunters. Since no one here are trained professionals, we should try to qualify any and all points especially provocative positions from the professional literature. From the same thread (page one) reply # 4: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.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. also.... Bears typically kill using brute force and do not seem to exhibit any stereotyped killing postures or behaviours as seen in canids and felids (R. Boertje, pers. comm.; J. Hechtel, pers. comm.). Polar bears and brown bears have been observed to attack their prey both with bites and crushing forepaw slaps, apparently to whatever region of the prey’s body is accessible (Murie, 1985; Boertje et al., 1988; Case & Stevenson, 1991; M. Ramsay, pers. comm; J. Hechtel, pers. comm.).Sacco, T. and Van Valkenburgh, B. (2004), Ecomorphological indicators of feeding behaviour in the bears (Carnivora: Ursidae). Journal of Zoology, 263: 41–54. shaggygod.proboards.com/index.cgi?board=generalinfo&action=display&thread=653and.... Lowry, L. (1987). Lowry, L.F., J.J. Burns, and R.R. Nelson. 1987. Polar bear, Ursus maritimus, predation on belugas, Delphinapterus leucas, in the Bering and Chukchi seas. Can. Field Nat. 101:141-146. PDF LINK: www.biodiversitylibrary.org/pdf3/011260900089248.pdf shaggygod.proboards.com/index.cgi?action=display&board=cetacea&thread=40&page=1
|
|
kiba
New Member
Posts: 28
|
Post by kiba on Mar 28, 2013 10:07:20 GMT -9
Yes, I read that info before watching these videos, is just that I watched the footage several times and the bears never throw any swipes, besides is reasonable to think that the polar bear beign a much more specialized hunter than the rest of the family would use a more "professional" and quick technique to dispatch their prey before they could escape to water, and the biting tech seems much more reliable in this aspect than swipes to secure prey, besides those claws marks on the walruses could been inflicted post mortem, just saying. Regards, Kiba.
|
|
|
Post by grrraaahhh on Apr 1, 2013 12:14:54 GMT -9
Yes, I read that info before watching these videos, is just that I watched the footage several times and the bears never throw any swipes,
Ignoring the brevity of such rare video footage (adult walrus predation itself is also infrequent) the polar bear’s highest priority is to prevent the walrus from escaping to the water. Grappling, dragging and pulling the injured bull walrus onto the ice (followed by some form of coup de grace or any combination of lethal actions) is the bear’s best option giving the proximity to the water. If hypothetically we could again capture on film such an event I would prefer overwintering conditions (see relating literature) where water access is limited to those adult walrus restricted by frozen sea ice. Under these conditions we would likely see a wider range of polar bear hunting methods; however, these are the harshest and most dangerous of conditions (as opposed to any melting conditions) in which to film.
besides is reasonable to think that the polar bear beign a much more specialized hunter than the rest of the family would use a more "professional" and quick technique to dispatch their prey before they could escape to water,
Yes, polar bears have specialized hunting skillsets especially when it comes to killing their main meal: seals. Seals dominate the polar bear’s diet (it’s either feast or famine) for both genders. From the literature we know that adult walrus victims are taken by adult male polar bears.
and the biting tech seems much more reliable in this aspect than swipes to secure prey, besides those claws marks on the walruses could been inflicted post mortem, just saying. Regards, Kiba.
If the walrus heads were examined then they were not consumed. What then would be the motive and explanation for the deep puncture wounds post mortem? Both the author (arguably the world’s most renowned polar bear biologist) and examination speculation of damaging paw swipes as the likely cause of death seems likely.
P.S. Sorry, I did not reply sooner. The motherboard on one of my laptops died/crashed.
|
|
|
Post by warsaw on Feb 11, 2016 11:52:01 GMT -9
|
|