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Bears
Bears as Predators ~
Bears as Predators ~
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Bears as Predators ~
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Post #166 appears like the dead whale was cut-up with a chainsaw - looks like neatly-cut square chunks of meat.
 
The Bears are Awake!
On February 28, Megan and I were hiking on wolf tracks in separate areas, and nearly simultaneously came across grizzly bear tracks. This is quite early, since the bears usually come out mid- to late-March. The second I came across the fresh grizz tracks, all of my senses came alive. And just moments before, I had blundered through an old bison carcass. Yellowstone, in an instant, has changed. For us, we can no longer saunter along with our heads down, following wolf tracks, getting lost in our thoughts. To do so could be fatal. The bears are very hungry and also very protective of any food they find. During normal winters, there is plenty of winter-killed elk and bison for the bears to scavenge on, but this winter has been far from normal. All of our necropsied kills have plenty of marrow fat remaining and we have found no animals that appeared to die due to the winter, so the bears will probably have to do some hunting for themselves or steal kills from the wolves. Later in the week, we were alerted to a bison carcass by Caroline, an interpretive ranger. With much yelling and eyeing of the forest edges, we flushed the 30+ ravens off the carcass as we approached. The necropsy found significant subcutaneous hemorrhaging on the hump of the very healthy (lots of fat in the hump and marrow) cow bison, indicating that she was killed by a bear. Grizzly bears often attack from the front, as opposed to wolves, which typically attack from the rear. The bears basically give their prey a good swat in the face or jump them from the side and latch onto their back.  *This image is copyright of its original author http://www.aspiringecologist.com/2010_03_01_archive.html  (03-15-2017, 02:45 AM)Polar Wrote: A adult male bear attacks and kills a young bear cub at a feeding site: Do you guys have any info on this site as far as bears compared to tigers and lions? I was in a youtube debate with a bunch of people, and you had a bear guy, vs a bunch of tiger guys, and then some lion fans, from what I saw and I think it was pretty legit, the bears were some tough customers, or at least quite strong in combat, which I guess you'd expect. But I'm just wondering if anyone has any weights on bears, as some people were saying they don't generally reach 1,000lbs and the average is like 800 lbs for a Kodiak, so I was thinking, if that's the average, that's still pretty heavy, because the average lion or tiger would be half that. (03-15-2017, 03:02 AM)Haymaker Wrote:(03-15-2017, 02:45 AM)Polar Wrote: A adult male bear attacks and kills a young bear cub at a feeding site: We try our best not to turn this site into an animal vs animal debate, so lion vs tiger vs bear isn't respectable here. Anyway, bears are extremely durable and intelligent fighters when it comes to interspecies fighting, and brown bears weigh slightly more than a lion at about 490-pounds. 800-pounds sounds good for a Kodiak male, pre-autumn right after hibernation ends and summer starts. Then when hibernation is near, they easily exceed 1000+ pounds. (03-15-2017, 03:06 AM)Polar Wrote:(03-15-2017, 03:02 AM)Haymaker Wrote:(03-15-2017, 02:45 AM)Polar Wrote: A adult male bear attacks and kills a young bear cub at a feeding site: Well when you see these nature docs as kids with these huge bears battling and the fat rolling all over the place, I mean they look extremely deadly, I wouldn't think a cat would have the durability in the body to withstand that kind of power, plus I would think the bear would outlast a bigcat as far as wind. I'm not sure about the lion though, because their were some lion guys that dropped a whole slew of accounts, I don't have all the info to verify them, but they seemed compelling to say the least and surprising, perhaps the mane aids them in some way, but I would think the mane wouldn't do much to a bear as the bear is too strong, unless it just allows for more wiggle room, which I suppose it could. The bear could be trying to bite through, and getting mane, and then right as its about to penetrate the lion maneuvers, and keeps that up, the addition of moving and keeping away from the bites with the mane perhaps could work. But if a lion didn't move, and was just motionless, I suppose then a bear or a tiger could just start clawing right through and reach the actual skin and vulnerable parts. At the same time, I think whether its a lion or a tiger both cats are endanger of getting any area of their body crushed in a serious bear hug. (03-15-2017, 03:19 AM)Haymaker Wrote:(03-15-2017, 03:06 AM)Polar Wrote:(03-15-2017, 03:02 AM)Haymaker Wrote:(03-15-2017, 02:45 AM)Polar Wrote: A adult male bear attacks and kills a young bear cub at a feeding site: Yep. Even large bears can be just as agile as big cats and with even more stamina. Both have prowess in their own ways. (03-15-2017, 03:35 AM)Polar Wrote:(03-15-2017, 03:19 AM)Haymaker Wrote:(03-15-2017, 03:06 AM)Polar Wrote:(03-15-2017, 03:02 AM)Haymaker Wrote:(03-15-2017, 02:45 AM)Polar Wrote: A adult male bear attacks and kills a young bear cub at a feeding site: He Polar do you know why my post don't show up on this site, I post something and it like its not there or it say it has to go through some approval, I'm a new member so I wasn't sure how it works. I got some private messages from some people, I can't even read them, can you tell the mods or something, not sure who runs the site.
Grizzly bears hunting musk ox...
pubs.aina.ucalgary.ca/arctic/Arctic35-4-545.pdf Muskox Bull Killed by a Barren-Ground Grizzly Bear, Thelon Game Sanctuary, N . W. T. ANNE GUNN’ and FRANK L. MILLER INTRODUCTION Muskoxen and barren-ground grizzly bears are relatively common along the banks of the Thelon River in the Thelon Game Sanctuary. In June 1981 we were flying a helicopter search of the Thelon River area during a study of water crossings used by barren-ground caribou (Rangifer tarandus groenlandicus). In the early afternoon of 23 June we were flying eastward when we spotted a grizzly bear standing on its hind legs among willow (Sulix spp.) bushes in a clearing surrounded by black spruce (Picea mariana) on the north shore. As there were two gulls (Larus spp.) in attendance, indicating the possibility of a kill, we circled closer and could then see a dead muskox on the ground near the bear. The grizzly bear alternately reared up and dropped onto all fours as we came close and when the helicopter was about 100-150 m away, the bear galloped away. We landed near the carcass of an adult muskox bull lying on its left side. The carcass was intact except for some exposed flesh and head wounds. The nose was tom away and the nasal turbinal bones were crushed and the cartilage torn. The right ear was split and torn away at the base where there was a penetrating wound into the skull. Traumatized areas were hemorrhagic, indicating that the wounds were inflicted on a living animal. The hide and musculature had been removed in the lumbar and thoracic areas, exposing the vertebrae and the right scapula. The internal organs were still intact and warm to touch. Subsequent histological examination of the dental annuli of a first incisor indicated that the muskox bull was 9-10 years old. The greening sedges (Carex spp.) immediately around the carcass were trampled and we backtracked along a disturbed path to a heavily trampled area of 5 m in diameter about 15 m away. The willow bushes peripheral to that trampled area were flecked with blood clots and clumps of blood-stained muskox wool. The ground cover was beaten down and the ground surface disturbed in many places with footprints pushed 10-15 cm or more into wet soil. We suggest that the grizzly bear surprised the muskox bull while it was grazing on sedge (indicated by rumen contents). The bear most likely grabbed the bull above the muzzle. In response, the bull must have braced its front legs and tried to dislodge the bear, suggested by front-foot hoof prints driven deep (15 cm) into the churned-up ground. Either the bull collapsed or the bear swung him off balance. At that point, the bear probably transferred its bite to just below the back of the bull’s horn boss. After making the kill, the bear dragged the carcass to where we found it, and had begun feeding when we interrupted. We returned about 48 hours later and found a light grey wolf (Canis lupus) and a grizzly bear whose colouring suggested it was not the bear that had made the kill. The carcass was dismembered and had settled into the wet ground. Most of the muscle masses and the internal organs had been consumed and the limb bones were scattered around the hide. The rumen had been pulled from the carcass but had not been fed on. The destruction of the facial area was also the mode of attack of a barren-ground grizzly bear killing a caribou cow whose carcass we found on the Beverly caribou herd’s calving ground, northeast of the Thelon Game Sanctuary, in June 1981. Griffel and Basile (1981) described puncture wounds in the frontal or jugal bones of 109 of 332 bearkilled sheep (Ovis aires) in Idaho. The facial area is richly innervated, and Mystervd (1975) in Griffel and Basile (1981) suggested that unconsciousness and hypoxic asphyxiation would follow severe and sudden injury to that area. Also, the seizing of the muskox bull’s muzzle would reduce chances of the muskox using its horns to gore the bear and increase the bear’s chances of throwing the muskox off its feet. Solitary muskox bulls usually seem particularly alert, and their speed of response, size, strength, thick coat and horns must combine to make them a formidable quarry even for a grizzly bear. The location of this kill, at the edge of a small clearing where ambush by rushing from nearby cover was possible, suggests that the kill was opportunistic. The muskox bull was probably so intent on foraging on the new growth of sedges 10-20 cm high that he was not aware of his attacker until it was too late. The femoral marrow fat was pinkish-white and firm, suggesting good nutritional status, and we did not observe any obvious infirmities that would have made the bull particularly vulnerable. Tener (1965) summarized predation on muskoxen and noted that Pederson’s report of a possible kill by a polar bear (Ursus rnaririrnus) may be the only reported instance of bear predation. He further commented that predation by barren-ground grizzly bears is rare, since up to 1965 only Hornby (1934, in Tener, 1965) had observed bears feeding on muskoxen on the banks of the Thelon River. In the late 1970s A.M. Hall (pers. comm.) observed grizzly bears feeding on muskox carcasses along the banks of the Thelon River (see photograph of grizzly bear sleeping near partiallyeaten bull muskox in Hall, 1980). In 1978, on the banks of the Thelon, Hall observed three muskox carcasses on which grizzlies had fed, but he could not determine whether the bears had killed or were scavenging the muskoxen. Hall (pers. comm.) believes that grizzly bear predation on muskoxen is high, especially on solitary bulls along the Thelon River, probably because the dense willow stands favour surprise ambushes. In June and July 1981, we saw only solitary bull muskoxen feeding in the willow stands, which leads us to the same supposition. Within 40 km of the carcass described in this paper, during the same flight, we observed five other grizzlies on the north shore. Pegau (1973) briefly described an apparent kill of a 2- or 3-yearold muskox by a bear but the carcass was almost completely consumed, so scavenging could not be ruled out. The carcass was found on the Seward Peninsula, Alaska, where Grauvogel (1979) speculated that the slow rate of increase of the transplanted muskox herd might be partially attributed to grizzly bear predation on muskox calves, though no evidence was cited. Our account of an apparently healthy, prime adult muskox bull that was killed by a grizzly bear is the first documentation of such an event.
Grizzly hunting seals on the ice...
http://www.eurekalert.org/pub_releases/2...030905.php PUBLIC RELEASE: 9-MAR-2005 Grizzlies set to invade high Arctic? NATURAL SCIENCES AND ENGINEERING RESEARCH COUNCIL The telltale paw prints with huge 10 centimetre-long nails spoke volumes. But now definitive corroborating DNA evidence seals the case of the most northerly sighting of a grizzly bear. The discovery fuels mounting evidence that Canada's High Arctic is no longer the sole preserve of the polar bear - Nanuk is having to make room for its southern cousin. The evidence of the barren ground grizzly bear (Ursus arctos) was discovered on Melville Island, an uninhabited part of the western Arctic archipelago 1,500 kilometres due north of Yellowknife, and 1,000 kilometres north of the Arctic Circle. "We know grizzlies go out on the sea ice to hunt seals, but no one has ever seen one that far north," says Dr. John England a geology professor and the NSERC Northern Chair at the University of Alberta. Dr. England got his first glimpse of the surprising Melville Island grizzly bear from the air during a helicopter ride to a geology research site in 2003. He photographed mid-distance shots of the large bear with characteristic grizzly features including a prominent shoulder hump, dark brown hair on and around the rear legs, and faded (grizzled) hair on the rest of the body. Then in the summer of 2004, Dr. England's research group found physical proof that a grizzly bear was indeed calling Melville Island home. Near a cabin used by researchers for temporary stop-overs, they found grizzly bear paw prints in the mud. And from the cabin's outside walls and a guy wire attached to the roof they collected two intriguing brown hairs. These were sent for analysis to Wildlife Genetics International Inc. in Nelson, British Columbia, one of the world's premier bear DNA labs. The result: the genetic analysis pointed to a male barren ground grizzly bear, rather than a Viscount Melville polar bear, the variety known to inhabit the Melville Island area. During the past 15 years there have been more and more sightings for barren-ground grizzlies on the sea ice in the Arctic from the Beaufort Sea to Hudson Bay. They're also known to be able to survive the winter and den on Victoria Island, the island separated from Melville to the north by Viscount Melville Sound. The geologists, now bitten with the grizzly bear research, emphasize that they are not wildlife biology experts. Nonetheless, they say the discovery of a grizzly bear on Melville Island raises numerous issues. Could grizzlies move east to one day take up home on Ellesmere Island, in the heart of polar bear country? Could polar bears in the wild interbreed with brown bears, their evolutionary close cousins, as has occurred at least once in captivity? What impact will grizzlies, already known to prey on polar bear cubs, have on these northern bears? For now, however, the greatest issue might be for the geologists themselves, says Dr. Jonathan Doupé, a postdoctoral researcher working with Dr. England. "We have bear safety courses when we go up there, and people would normally say you don't have to worry about grizzlies because it's really just polar bear country," he says. "But I think that's no longer the case." Dr. England notes that the grizzly bear find is a highly visible example of important changes occurring in the Arctic. "The Arctic is very large and diverse, and this complex but exciting environment is just coming into focus for Canadians in general. It's now a mainstream issue." |
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