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Post by Gorilla king on Jun 28, 2021 20:50:52 GMT -5
ADULT FEMALE BROWN BEARS INTERACTIONS WITH WOLVES:
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Post by Gorilla king on Jun 28, 2021 20:52:04 GMT -5
GRIZZLY DISPLACES 14 WOLVES FROM KILL:
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Post by Gorilla king on Jun 28, 2021 20:55:50 GMT -5
King of the carnivores: How bears, wolves & jaguars stack up against pumas
Where the hunting grounds of apex predators overlap, there are always winners and losers. Large carnivores use their brawn to force smaller rivals off meals, or worse: to wipe out the opposition entirely. Others use strength in numbers to gain ground and resources. It's a struggle for dominance that America's second-largest cats know well, a new study shows.
A map showing where pumas are dominant and subordinate across their range. Research from global wild-cat conservation organisation Panthera reveals that in almost half of their expansive range across the Americas, pumas are outmatched by at least one other large predator in the contest for food, space and resources. While the cats certainly rank at the top of the food chain, they are forced to share this position with contenders like wolves, bears and jaguars. The study found that pumas came off second best to other large predators in as much as 47.5% of their 22,735,268 square-kilometre range – a habitat that's greater than any other large land mammal in the Western Hemisphere.
To figure out just how the tawny cats stacked up against their carnivorous competition, Panthera Puma Program lead scientist, Dr Mark Elbroch, and Anna Kusler, a graduate researcher with Panthera's Teton Cougar Project, combed through 60 years of scientific literature and flagged anything featuring interactions between mountain lions and other carnivores (hardly glamorous, but wildlife research isn't all darting elephants and tracking jaguars). Using 64 sources to assess dominance among pumas and other apex predators, they found that pumas are often outranked by black bears, grizzlies, wolves and jaguars, but are dominant over maned wolves and coyotes.
"Wolves seem to influence pumas the strongest," Dr Elbroch writes in a blog post outlining the findings. "Wolves kill all age classes of pumas, frequently chase and harass them, and push them from their kills." Where wolves and mountain lions share ground, it's the cats that are usually forced to surrender territory, shifting their movements away from open plains, and instead skulking in forests and over rockier terrain to better evade prowling wolves. The big cats may even adjust their prey preferences, targeting deer and other animals rather than elk.
A puma monitored by Panthera pushed off his kill by a wolf. Pumas don't always settle for the subordinate position, though; the cats sometimes emerge victorious in scuffles with rivals, and have even been recorded killing their canid adversaries on occasion (usually lone wolves that lacked the competitive edge that comes with rolling in a pack). For predators jostling for top spot on the food chain, strength in numbers can make a big difference. Wolves outranked pumas in 78% of the sources turned up by Elbroch and Kusler – an impressive track record that mostly came down to a numbers advantage.
Size plays a big role, too. Larger animals will almost always come out on top, which is why pumas outrank smaller mesocarnivores like ocelots and lynxes, but often lose to the far heftier bear species. But when it comes to jaguars, the contest is a little less clear-cut. "Evidence that jaguars are dominant over pumas is strongest in areas where jaguars are large and weigh considerably more than pumas, but more ambiguous in Northern Mexico, where the two species are similar in size," Elbroch explains. It's unclear if pumas actually outrank their spotted cousins (that's a research topic waiting to be explored), but the results of the study show that size certainly does matter.
Are-pumas-subordinate-carnivores_2018-02-02.jpg The apex predators of North and South America and their relative competitive relationship with pumas (E). Bold arrows denote dominance, and point from the dominant species to the subordinate. Thin arrows denote some evidence to the contrary. (A) gray wolf (Canis lupus), (B) grizzly bear (Ursus arctos), (C) American black bear (Ursus americanus), (D) jaguar (Panthera unca), (E) puma (Puma concolor), (F) maned wolf (Chrysocyon brachyurus), (G) coyote (Canis latrans). Drawings by Mark Elbroch/Panthera Clashes for the number-one spot among America's large carnivores are complex, and there's still much we don't understand about these interactions, or the impact they have on the ecology of the species involved (and the other critters that depend on them). Puma numbers are heavily controlled through hunting in order to reduce conflict with livestock and humans – clashes that are almost inevitable for a cat with such a massive home range. For Elbroch, it's important to understand how predator dominance affects these cats before we put them in the crosshairs.
"It's incredibly difficult to determine what is a 'sustainable' puma hunt and what is not – instead, puma management must be reactionary, carefully following populations to determine whether they are in decline, and rapidly adjusting hunting pressure accordingly," he argues.
Until we better grasp the impact of other carnivores on mountain-lion populations, hunting should be reduced – at least in areas where wolves and grizzlies are expanding their range, says Elbroch. If the cats can't cope with competition from other predators, they certainly don't need any more from us.www.earthtouchnews.com/conservation/conservation/king-of-the-carnivores-how-bears-wolves-jaguars-stack-up-against-pumas/
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Post by Gorilla king on Jun 28, 2021 20:58:34 GMT -5
The apex predators of North and South America and their relative competitive relationship with pumas (E). Bold arrows denote dominance, and point from the dominant species to the subordinate. Thin arrows denote some evidence to the contrary. (A) gray wolf (Canis lupus), (B) grizzly bear (Ursus arctos), (C) American black bear (Ursus americanus), (D) jaguar (Panthera unca), (E) puma (Puma concolor), (F) maned wolf (Chrysocyon brachyurus), (G) coyote (Canis latrans). Drawings by Mark Elbroch/Panthera
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Post by Gorilla king on Jun 28, 2021 21:00:29 GMT -5
Female grizzly bears do a great job protecting their cubs from wolves:
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Post by Gorilla king on Jun 28, 2021 21:01:58 GMT -5
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Post by Gorilla king on Jun 28, 2021 21:03:46 GMT -5
Carcass-stealing by grizzlies doesn’t mean wolves kill more
BILLINGS – Research that compared Yellowstone National Park grizzly bear and wolf interactions with those same animals in Sweden has produced a surprising finding: brown bear presence in both ecosystems reduces the wolf kill rate.
“It’s a baffling finding,” said Doug Smith, Yellowstone’s wolf biologist. “To be honest, for 20 years I’ve been saying bears increase wolf kill rates because bears steal so many carcasses.”
That data from two very different ecosystems pointed to the same conclusion helped convince Yellowstone bear biologist Kerry Gunther that the research was “not just a fluke.”
The study’s lead author was Aimee Tallian, a Utah State University wildlife ecologist and former Yellowstone research assistant. Eleven international co-authors helped with the National Science Foundation-funded project that allowed Tallian to spend a year working in Sweden.
Different worlds
The research area in south-central Sweden is very different from Yellowstone, Tallian noted. Roads criss-cross the dense forest because it is logged. That means researchers could drive to most locations, compared to Yellowstone where hours spent hiking is more often the norm.
“It’s heavily managed by humans, but there are still a lot of woods and remote areas,” she said.
Yellowstone is also unusual in that grizzly-wolf interactions are sometimes seen along the main roads where they are photographed by tourists or studied through spotting scopes. Seeing the animals in Sweden is rare, partly because they are still hunted populations.
Research says
Tallian said the assumption that the presence of an apex predator like grizzlies would drive wolves to hunt and kill more prey was never written down anywhere, but was a commonly held belief.
“The results were the opposite of what we expected,” she said. “I double-checked the data so many times thinking, ‘What did I do wrong?’”
“Our results challenge the conventional view that brown bears do not affect the distribution, survival or reproduction of wolves,” stated the research paper, which was published in the “Proceedings of the Royal Society B” on Feb. 8.
“Although the outcome of interactions between bears and wolves at carcasses varies, bears often dominate, limiting wolves' access to food,” the paper said. “Furthermore, our findings suggest that wolves do not hunt more often to compensate for the loss of food to brown bears. In combination, this implies that bears might negatively affect the food intake of wolves," so wolf populations that live within the same geographical area as brown bears may see effects on their fitness.
King of the kill
Past research by Smith and his crew in Yellowstone’s remote, bear-rich Pelican Valley have found that, between March and October, virtually every wolf kill is taken over by a grizzly bear.
“Wolves get a lot of food stolen from them by grizzlies,” Smith said.
Gunther said it is common in Yellowstone for grizzlies to usurp wolf kills within hours, if not days. Takeovers by females with cubs is less common because the wolves will threaten, and sometimes kill, the young bears.
“The missing piece was: What does that do to wolf kill rates?” Smith noted.
Tallian said many assume that wolves are efficient and effective killers. But previous research in Yellowstone has shown that summer is a lean season, the same time that grizzlies are out of hibernation competing for food and there’s no snow to slow down the wolf’s favorite prey, ungulates like elk. Faced with a food shortage, packs break up into smaller groups with wolves often dining on smaller and more varied prey than in winter.
So when wolves do kill a large animal, like an elk, it may be easier to stick around and wait for an encroaching grizzly to leave than to make another kill, Smith and Tallian agreed.
“One of the implications is that maybe bears do have some impact on the fitness of wolves, because bears steal their food, there’s a net food loss when bears are around,” Tallian said.
New question
Tallian’s research prompts the question: “Have wolves increased bears? That would be a huge headline,” Smith said. “But we can’t back that up.”
Grizzly bear populations in the Greater Yellowstone Ecosystem were climbing in the 1980s, before wolves returned to the landscape in 1995, Gunther said.
“Certainly wolves have played a role because there is more meat on the landscape that bears have access to,” Gunther said.
But there are also fewer winterkill animals awaiting bears when they leave hibernation in spring, and he noted that wolves occasionally kill a grizzly cub.
“So there are positives and negatives,” he said.
Tallian’s research helps fill one gap in a larger story about ecosystems that are incredibly complicated, interwoven and which, in many ways, operate beyond the scope of human understanding.
“This is one more piece of the jigsaw puzzle,” Smith said.
www.google.com/amp/s/missoulian.com/news/state-and-regional/carcass-stealing-by-grizzlies-doesn-t-mean-wolves-kill-more/article_589bb384-3236-5a8b-ba8f-d32e3c0ec3f3.amp.html
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Post by Gorilla king on Jun 28, 2021 21:05:44 GMT -5
From the above source:
In North America's Yellowstone National Park, hungry wolves wait to access their elk kill as grizzly bears feast on the spoils. Utah State University ecologist Aimee Tallian and colleagues report wolf kill rates fall in the presence of brown bears on two continents.
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Post by Gorilla king on Jun 29, 2021 18:53:25 GMT -5
GRIZZLY BEAR CHASES WOLF OFF A CARCASS.
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Post by Gorilla king on Jun 29, 2021 18:57:56 GMT -5
DOUG PEACOCK:
"REINTRODUCING WOLVES TO A PLACE LIKE YELLOWSTONE MIGHT MAKE FOR ALOT OF EXTRA GRIZZLY FOOD.”
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Post by Gorilla king on Jun 29, 2021 18:59:28 GMT -5
WOLVES CON A GROUP OF BEARS:
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Post by Gorilla king on Jun 29, 2021 19:01:04 GMT -5
Nature red in tooth and claw: The bloody moment a bear decides to take on a whole pack of wolves and steal the deer they've just killed
WARNING GRAPHIC CONTENT Grizzly bear tried to steal a dead deer that was killed by a pack of wolves in the Rocky Mountains in Montana The wolves then fought back but the bear took each of them one and managed to claim the prey for himself Spectacular shots of the bloody battle were captured on camera by British holidaymaker Tom Littlejohns This is the bloody moment a bear takes on a whole pack of wolves in an incredible brawl over a dead deer.
To protect their dinner, the brave wolves attempted to warn off the bear but one by one were swatted away by the grizzly's giant paws.
One close-up picture shows one wolf baring its teeth on the blood-stained snow as the bear continues to fight.
While the other photos show the lone bear enjoying a deer supper after scaring off its rivals.
The amazing photographs snapped by Mr Littlejohns, 75, a logistics consultant from Guildford while on a trip to the Rocky Mountains in Montana.
He said: 'In these particular images, I saw the change from relatively docile and almost large cuddly wolves become unbelievably ferocious both with each other and prepared to take on a fully grown Grizzly.'
Gray wolves were virtually wiped out in the lower 48 states by the 1940s, but thanks to a highly successful reintroduction program in central Idaho and Yellowstone National Park, the population is once again back.
By the end of 2012, the estimated population in the Northern Rockies region was 1,674 wolves.
By comparison, there are only about 1,500 grizzlies left in the lowest 48 states, with about 800 living in Montana alone and another 600 or so in Wyoming, in the Yellowstone-Teton area.
The scene captured by Mr Littlejohns is actually somewhat of a common occurrence, with grizzlies locating a carcass with its keen sense of smell once an animal has been killed by a wolf.
The spectacular action shots taken by British holidaymaker Tom Littlejohns, show the pack of wolves enjoying their prey until they are interrupted by a six-and-a-half-foot long bear.
As the wolves and the grizzly compete for the kill, one wolf may try to distract the bear while the others feed. But such is the size of the bear, that if wolves become aggressive, it can defend itself by sitting, eliminating being attacked at its hind legs. Fights rarely end in death or serious injury to either animal.
www.google.com/amp/s/www.dailymail.co.uk/news/article-4124734/amp/Nature-red-tooth-claw-bloody-moment-bear-decides-pack-wolves-steal-deer-ve-just-killed.html
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Post by Gorilla king on Jun 29, 2021 19:02:41 GMT -5
LOOKS LIKE A GRIZZLY BEAR DISPLACED 5 WOLVES
Reports of another bison carcass in Lamar Valley garnered our attention. Observers reported a grizzly bear and five more wolves around the carcass so we packed up and moved on. By the time we arrived, the wolves were nowhere to be found. The male grizzly bear, however, was sleeping on top of the carcass. Fall is the time of hyperphagia (over-eating) for bears and an adult grizzly bear may consume upwards of 20,000 calories a day. It’s worthwhile for a bear to defend its food until it’s consumed its fill.
Male grizzly bear sleeping on/ defending a bison carcass in Lamar Valley, Yellowstone National Park.
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Post by Gorilla king on Jun 29, 2021 19:05:15 GMT -5
BEAR KILLS WOLF IN A LONDON MENAGERIE:
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Post by Gorilla king on Jun 29, 2021 19:07:26 GMT -5
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Post by Gorilla king on Jun 29, 2021 19:10:51 GMT -5
Grizzly Bear, Ursus arctos, usurps Bison calf, Bison bison, captured by Wolves, Canis lupus, in Yellowstone National Park, Wyoming
We describe an adult Grizzly Bear (Ursus arctos) usurping a Bison (Bison bison) calf from a pack of five Wolves (Canis lupus) attempting to kill the Bison in Yellowstone National Park during early spring. Five Wolves grabbed the hind end and neck of the calf while it was trailing behind two adult male Bison. In 3 minutes a Grizzly Bear arrived and displaced the two Wolves attacking the hind end. For 1 minute the Grizzly Bear attacked the rear of the Bison while three Wolves attacked the front end. The Grizzly Bear subsequently pulled the struggling calf from the Wolves and made the kill. The Wolves were unable to displace the Grizzly Bear from the carcass. Our observation demonstrates the capacity for Grizzly Bears to exploit the predatory abilities of Gray Wolves restored to Yellowstone National Park. Kleptoparasitism by Grizzly Bears on Wolf-captured ungulates may be a selective pressure promoting group living in Wolves, and could provide an important new food resource to threatened Grizzly Bears in the Greater Yellowstone Ecosystem.
www.researchgate.net/publication/286981176_Grizzly_Bear_Ursus_arctos_usurps_Bison_calf_Bison_bison_captured_by_Wolves_Canis_lupus_in_Yellowstone_National_Park_Wyoming
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Post by Gorilla king on Jun 29, 2021 19:17:02 GMT -5
SOME IMPORTANT NOTES FROM THE SOURCE ABOVE:
... Extended capture duration was likely due to the wolf's small size and limited ability to subdue prey. Unlike big cats (Hornocker 1970;Schaller 1967Schaller , 1972, or grizzly bears (Ursus arctos) (MacNulty et al. 2002), wolves lack mass, muscular forelimbs, and longer claws that enable other carnivores to quickly grab and overcome prey. Wolves also cannot generally deliver a quick killing bite commonly used by the big cats. ...
... For instance, female moose will aggressively protect their offspring from attacking wolves (Mech 1966a;Peterson 1977). In herd prey, such as bison (Carbyn et al. 1993;MacNulty et al. 2002) and muskoxen (Tener 1954;Gray 1987;Mech and Adams 1999), non-target individuals will shield the target individual, and attempt to drive off attacking wolves. To minimize their risk of injury from non-target prey, wolves must often wait and watch for an opportunity to strike at the target. ...
... While the tendency of wolves to watch bison may be the result of fear, it also reflects a lack of fear among bison towards wolves. For instance, targeting usually follows an approach because generally bison do not flee from wolves (Smith et al. 2000), and attacks on individuals located at the periphery of the herd often occur while non-target individuals elsewhere in the herd continue to graze uninterrupted (MacNulty et al. 2002). ...
... Similar to bear-felid interactions, bears often kleptoparasitize wolf kills, both in North America (Ballard et al. 2003;Smith et al. 2003) and Europe (Milleret 2011;Ordiz et al. 2015). The outcome of interactions between bears and wolves at carcasses varies, but in general, bears often dominate and limit the access of wolves to kills (Boertje et al. 1988;MacNulty et al. 2001). For instance, Ballard et al. (2003) compiled 108 direct bear-wolf interactions in North America, outside Yellowstone National Park, and 57% of them occurred at kill sites, with bears dominating in most of those encounters (Ballard et al. 2003). ...
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Post by Gorilla king on Jun 29, 2021 19:19:02 GMT -5
WOLVES INTERACTIONS WITH NON-PREY
COUGARS AND BLACK BEARS ARE ABLE TO OVERPOWER AND EVEN KILL LONE WOLVES.
... There is extensive literature documenting gray wolves as the dominant competitor to black bears and cougars, through both interference competition (demonstrated by usurping prey carcasses and direct mortality; Ballard et al. 2003;Kortello et al. 2007;Hebblewhite and Smith 2010;Elbroch et al. 2015b) and exploitation competition (demonstrated by prey switching and spatiotemporal shifts by the subordinate competitors; Kortello et al. 2007;Ruth and Murphy 2010;Bartnick et al. 2013;Elbroch et al. 2015b). Wolves achieve this competitive domi- nance through their social nature, as cougars and black bears are able to overpower and even kill lone wolves (Rogers and Mech 1981;Ballard et al. 2003;Jimenez et al. 2008;Fremmerlid and Latham 2009). Through their capacity to effectively kleptoparisitize cougar kills, black bears have also demonstrated their ranking as a dominant competitor to cougars and can pose significant constraints on cougar fitness ( Murphy et al. 1998;Ruth and Murphy 2010;Elbroch et al. 2015a).
GRIZZLY BEARS GENERALLY PREVAILED IN INTERACTIONS WITH WOLVES, EVEN WHEN OUTNUMBERED BY WOLVES.
.. Almost half of the adult elk and all of the bison carcasses seen at site visits for grizzly bears during this study had wolf sign present. Grizzly bears generally prevailed in interactions with wolves, even when outnumbered by wolves (Ballard et al. 2003). Thus, during the active season, wolves may increase the availability of meat to adult grizzly bears, with the exception of females with cubs that are less likely to usurp wolf-killed ungulate carcasses ( Knight 1993, Ballard et al. 2003, Gunther and Smith 2004). ...
Full study here :
www.researchgate.net/publication/275651420_Wolf_interactions_with_non-prey
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Post by Gorilla king on Jun 30, 2021 20:58:03 GMT -5
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Post by Gorilla king on Jun 30, 2021 21:02:52 GMT -5
DOCUMENTARY FROM SPAIN TELLS OF HOW A BROWN BEAR KILLED AND DRAGGED A WOLF AWAY:
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