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Bear Strength - Printable Version

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RE: Bear Strength - GreenGrolar - 10-31-2019

Johnny Rex, I understand where you are coming from now. I totally agree that almost all species of  lions, tigers, leopards, wolves etc can kill humans too. However, I was referring to felines and canines as a whole. Most of the weasel family are too small to kill humans except the wolverine and honey badger plus there are some felines (e.g. house cats, African wild cats, scottish wild cats, black footed cat etc)  and canines (foxes, maned wolves) too small to kill humans. Hope we can come to an understanding here and I apologies for any misunderstanding.
Back to topic, bears do have good grappling techniques and powerful shoulder muscles. More info:


Code:
Strong muscles.

Bears are the bully-boys of the animal kingdom. Their strength is mainly in the muscles of their legs and shoulders. Unlike cats and dogs, which run on their toes for speed, bears walk on the flat soles of their broad feet, just as humans do. What bears lack in speed they make up for strength. Their powerful, mobile limbs can be put to good use digging, climbing, fishing, and fighting. They will attack others of their own kind and defend themselves ably from enemies. In a fight, a bear can do considerable danage an survives by sheer brute force. Male bears are generally much larger than females of the same species.

Page 12 (Bears and pandas by Michael Bright)
http://domainofthebears.proboards.com/thread/173/bear-strength?page=5


RE: Bear Strength - GreenGrolar - 10-31-2019

Some more info credited to King Kodiak:

The full paragraph here:


Of all the morphologic features that typify bears, the front limbs and associated skeletal infrastructure are the most distinctive. They are also diagnostic of the bear life strategy (see Life strategy). No other terrestrial vertebrate of its size--certainly no other large carnivore--has front limbs that are as flexible, powerfully built, and mounted with such dexterous paws. Nor do any comparable-sized carnivores have such out-sized claws...claws which are clearly "designed" to be powered by the muscular arms and shoulders to either climb trees, extract food from a durable matrix (i.e., dig), or grapple with and subdue large prey such as seals, moose, and elk. What follows is a summary of the evidence produced over the years elaborating on and substantiating the preceding thumbnail sketch. You will have to forgive me for the abundance that follows, but it is reflective of the extent to which I see this aspect of bear morphology as key to understanding the overall bear life strategy--as well as niche. 

This is the forepaw dexterity chart. (dexterity-Skill in performing tasks with the forepaws)


*This image is copyright of its original author


https://www.allgrizzly.org/front-limbs

http://domainofthebears.proboards.com/thread/540/strength-girth-comparison-bears-cats?page=20


RE: Bear Strength - Roberto - 11-03-2019

(10-30-2019, 02:18 PM)johnny rex Wrote:
(10-06-2019, 10:11 AM)Polar Wrote:
(09-05-2019, 05:15 PM)johnny rex Wrote:
(02-02-2019, 07:07 AM)GrizzlyClaws Wrote: Dog got pinned several times by a Black bear cub.






Bears can be said as natural born wrestlers. Just look at how male bears fight with each other. Those "paw swipes that break bones" stories maybe are just exaggerations, bears tend to use their forelimbs to hold and wrestle prey or competitor to the ground not swiping hard.

Those might not really be exaggerations. Depending on where they hit, a bear's super-dense paw may actually break the shoulder, chest, or pelvic area of a weaker big cat since they have greater radial robusticity and bone density than the feline. Radial robusticity (think of a wide-framed man throwing a hook) increases impact from the side with greater hip rotation.

If you mean "a weaker big cat" like a sick lion or tiger, smaller big cats such as a jaguar, a leopard, etc. yes maybe. Is there any book or source that said bears have greater bone density?

yeah, actually there is:

The following study details carnivore limb bone lengths and widths, which we can use to infer both limb and overall body robusticity.



Credits to Reddhole or Leopjag

Source: Bertram and Biewner, "Differential Scaling of Limb Bones in Terrestrial Carnivores and Other Mammalia", Journal of Morphology: 204 157-169: 1990



For years posters have debated the overall strength of individual species. Commonly people post pictures of individual animals that purport to show that one species is stronger than another. Unfortunately, these picture comparison are unscientific in that the individual animals could have thick fur, the pictures can be taken at flattering or unflattering angles, or the photos may be photoshopped.



A more scientific approach involves limb bone dimensions. Scientists have found that limb lengths and widths (especially humerus or upper arm bone and femur or upper leg bone) correlatate strongly with body mass. Of the two, limb bone width is generally the better measure because wider bones can support more body mass. Thus, an animal with relatively wider bones is usually a stockier and therefore more powerful animal (although individual muscles may not be).


This study details humerus, femur, radius (forearm bone), and tibia (lower leg bone) lengths and two measures of width - anterioposterior diameter (AP diameter) and mediolateral diameter (ML diameter). Another study in which Ursus and I have posted extracts before found that animals that run fast (cursors and ambushers to a lesser extent) tend to have relatively wide AP diameters in their limb bones compared to animals that run at lower speeds or less often (i.e bears, mustelids, etc.). Here is the relavant extract:


[img]https://i.imgur.com/SURl5dY.jpg" class="lozad max-img-size" alt="" title="">
*This image is copyright of its original author

For example, the cheetah has relatively robust limbs if we use AP diameter, but rather gracile limbs if we use ML diameter. As a result, I think ML diameter is the better measure because it leaves out limb bone thickening due to high speed running.



The humerus and radius robustness measures are also interesting from a grappling perspective. Animals that grapple with heavy prey tend to develop a relatively more robust humerus and radius to handle the high stresses involved in handling large prey. In fact humerus and radius robustness were two key morphological traits of cats that kill large vs,. small prey in the feline grappling study I posted a few months back.


The study used several mature adult specimens with roughly equal numbers of each sex when possible. I do not think sexual dimorphism should play much of a role since another study of feline limb bone dimensions did not show much change in relatively limb robusticity between sexes of each species.


*This image is copyright of its original author

Another thing to note is that animal limb bones become slightly more robust as they get larger all else being equal. The trend is not too significant until animals reach about 100-300 KG.


Below is the raw data. Also, note we can calculate radius/humerus and tibia/femur (i.e. mechanical advantage of the forearm and lower leg - lower values mean stronger forearms and more stable rear legs all else being equal) from this data.


*This image is copyright of its original author

*This image is copyright of its original author

Here are some general observations - mostly based off of ML diameter of the humerus (i.e. ML diameter of humerus/humerus length) unless otherwise noted.


1) The bears are extremely robust, even the smaller species, which should not have extreme thickening of the limb bones that larger species do. Most have humerus's as or more robust (based off of ML diameter) than any big cat.



Sun Bear: 9.6%

Sloth Bear: 11.67%

Black Bear: 9.7%

Giant Panda 9.7%



2) Lion and Tiger


Lion: 8.92%; 12.78%



Tiger: 8.57%; 11.37%



The lion has a more robust radius and tibia based off of ML diameter while the tiger's radius and tibia is more robust based off of AP diameter.



As most already know, the tiger has the lower (i.e. more advantageous) radius/humerus and tibia/femur ratios.


RE: Bear Strength - Roberto - 11-03-2019

Here Peter confirms, based on and his own personal experience, that even at similar size,  brown bears have more robust skeletons than tigers. Also, longer and heavier skulls. Tigers have it wider at the arches.

PETER
I've seen skeletons of both species next to each other. There's no question that skeletons of brown bears, even if the big cat and the bear are similar in size, are more robust. In the skull department, it's a close call. Bears have a somewhat longer and heavier skull, but tiger skulls are close and they're wider at the arches. Tiger also have significantly longer canines. 

page 115, post # 1711

http://redirect.viglink.com/?format=go&jsonp=vglnk_157273919049112&key=71fe2139a887ad501313cd8cce3053c5&libId=k2i87bbs0102ylrr000MAn7txcfsi&loc=http%3A%2F%2Fdomainofthebears.proboards.com%2Fthread%2F602%2Fpeter-most-respected-knowledgeable-tiger%3Fpage%3D1%26scrollTo%3D17567&v=1&out=https%3A%2F%2Fwildfact.com%2Fforum%2Ftopic-on-the-edge-of-extinction-a-the-tiger-panthera-tigris%3Fpage%3D115&ref=http%3A%2F%2Fdomainofthebears.proboards.com%2Fpost%2F17567%2Fedit&title=PETER%2C%20THE%20MOST%20RESPECTED%20AND%20KNOWLEDGEABLE%20TIGER%20FAN%20%7C%20Domain%20Of%20The%20Bears&txt=wildfact.com%2Fforum%2Ftopic-on-the-edge-of-extinction-a-the-tiger-panthera-tigris%3Fpage%3D115


RE: Bear Strength - Shadow - 11-03-2019

@Roberto I edited your posting and took off content, which had nothing to do concerning bears and what @johnny rex said/asked. It is ok to speculate at some level about things, but then again some topics are also.... sensitive in a way. So when postings start to show signs of tiger vs lion debates etc. not too much is tolerated. 

When posting things, focus should be in relevant information concerning topic. In this thread it´s bear strength, so comparisons between lions and tigers or lynxes and coyotes etc. are irrelevant. Keeping postings clear and focusing to relevant information what comes to thread makes it also easier for people interested to find information.

With current information it´s always open for speculation, that is a 200 kg tiger stronger than a 200 kg bear. It is totally different thing, that a 200 kg bear can still grow (depending of the bear and subspecies) and be in future a 400-500 kg "giant". But when we put a 200 kg tiger, lion and bear side by side... who knows. Everyone can speculate, but proving is totally another thing. Good to remember so, that not surprised when people always disagree. Real size does matter, when we have biggest predators side by side.


RE: Bear Strength - Shadow - 11-03-2019

I also deleted posting, which had nothing to do with strength, but was looking like trying to start bear vs tiger debate in other ways. I warn only this time, if anyone tries to start such debate in this thread, moderation happens. Bear strength is topic, bear vs tiger fight debates aren´t.


RE: Bear Strength - Roberto - 11-03-2019

Well, Johnny rex asked this at post # 211:

Is there any book or source that said bears have greater bone density?

So i answered perfectly with probably the only bone robusticity study that we have on forums. The answer is that even the smallest species of bear have more robust limb bones than big cats. (Humerus)

 The bears are extremely robust, even the smaller species, which should not have extreme thickening of the limb bones that larger species do. Most have humerus's as or more robust (based off of ML diameter) than any big cat.


Sun Bear: 9.6%

Sloth Bear: 11.67%

Black Bear: 9.7%

Giant Panda 9.7%

2) Lion and Tiger

Lion: 8.92%; 12.78%

Tiger: 8.57%; 11.37%


RE: Bear Strength - BorneanTiger - 11-20-2019

Grizzly pulls a bison carcass in Yellowstone National Park: 






RE: Bear Strength - Shadow - 11-20-2019

Nice find, that´s maybe the most impressive show of strength I´ve ever seen from big predators. That looked like to be intact carcass.


RE: Bear Strength - BorneanTiger - 11-20-2019

(11-20-2019, 04:14 PM)Shadow Wrote: Nice find, that´s maybe the most impressive show of strength I´ve ever seen from big predators. That looked like to be intact carcass.

A tiger was documented to have dragged a gaur's carcass (which 13 men couldn't move) for 12 meters (39.37 feet), but that's another topic: https://books.google.com/books?id=T37sFCl43E8C&lpg=PP1&pg=PA825&redir_esc=y#v=onepage&q=tiger%20dragged%20gaur%2012%20meters&f=false


RE: Bear Strength - Shadow - 11-20-2019

(11-20-2019, 05:26 PM)BorneanTiger Wrote:
(11-20-2019, 04:14 PM)Shadow Wrote: Nice find, that´s maybe the most impressive show of strength I´ve ever seen from big predators. That looked like to be intact carcass.

A tiger was documented to have dragged a gaur's carcass (which 13 men couldn't move) for 12 meters (39.37 feet), but that's another topic: https://books.google.com/books?id=T37sFCl43E8C&lpg=PP1&pg=PA825&redir_esc=y#v=onepage&q=tiger%20dragged%20gaur%2012%20meters&f=false

I don´t take that account seriously what comes to that gaur carcass, tiger and 13 men. There are many videos what comes to tiger dragging carcasses and in none they have showed ability to drag huge carcasses in the way like some old descriptions claim. Of course if wet grass and tiger drags something downhill, it might be difficult to drag that back uphill... 

In these things, what comes to animal strength I choose to believe what can be seen in countless video clips. And this performance by this bear was quite something. It practically lifted over half of that carcass and especially heavier part off the ground before it was turned. I´ve seen big cats to turn over carcasses, but never that big. And not in that way as this bear did. It didn´t just roll it over as I´ve seen some lions do.


RE: Bear Strength - GreenGrolar - 11-20-2019

(11-20-2019, 04:02 PM)BorneanTiger Wrote: Grizzly pulls a bison carcass in Yellowstone National Park: 




I just found this video on another forum. Was about to post it but looks like you beat me to it  Lol . Never doubted a grizzly bear is capable of dragging a bison carcass.


RE: Bear Strength - Pckts - 11-20-2019

(11-20-2019, 07:04 PM)GreenGrolar Wrote:
(11-20-2019, 04:02 PM)BorneanTiger Wrote: Grizzly pulls a bison carcass in Yellowstone National Park: 




I just found this video on another forum. Was about to post it but looks like you beat me to it  Lol . Never doubted a grizzly bear is capable of dragging a bison carcass.

I didnt see him drag it but he was able to flip the carcass which was impressive.


RE: Bear Strength - Pckts - 11-20-2019

(11-20-2019, 06:50 PM)Shadow Wrote:
(11-20-2019, 05:26 PM)BorneanTiger Wrote:
(11-20-2019, 04:14 PM)Shadow Wrote: Nice find, that´s maybe the most impressive show of strength I´ve ever seen from big predators. That looked like to be intact carcass.

A tiger was documented to have dragged a gaur's carcass (which 13 men couldn't move) for 12 meters (39.37 feet), but that's another topic: https://books.google.com/books?id=T37sFCl43E8C&lpg=PP1&pg=PA825&redir_esc=y#v=onepage&q=tiger%20dragged%20gaur%2012%20meters&f=false

I don´t take that account seriously what comes to that gaur carcass, tiger and 13 men. There are many videos what comes to tiger dragging carcasses and in none they have showed ability to drag huge carcasses in the way like some old descriptions claim. Of course if wet grass and tiger drags something downhill, it might be difficult to drag that back uphill... 

In these things, what comes to animal strength I choose to believe what can be seen in countless video clips. And this performance by this bear was quite something. It practically lifted over half of that carcass and especially heavier part off the ground before it was turned. I´ve seen big cats to turn over carcasses, but never that big. And not in that way as this bear did. It didn´t just roll it over as I´ve seen some lions do.
Just out of curiosity, how many videos have you actually seen of Tigers dragging Gaur or Buffaloes?

The young male in Kanha drags a Gaur Cow fairly easy.


RE: Bear Strength - Shadow - 11-20-2019

(11-20-2019, 07:37 PM)Pckts Wrote:
(11-20-2019, 06:50 PM)Shadow Wrote:
(11-20-2019, 05:26 PM)BorneanTiger Wrote:
(11-20-2019, 04:14 PM)Shadow Wrote: Nice find, that´s maybe the most impressive show of strength I´ve ever seen from big predators. That looked like to be intact carcass.

A tiger was documented to have dragged a gaur's carcass (which 13 men couldn't move) for 12 meters (39.37 feet), but that's another topic: https://books.google.com/books?id=T37sFCl43E8C&lpg=PP1&pg=PA825&redir_esc=y#v=onepage&q=tiger%20dragged%20gaur%2012%20meters&f=false

I don´t take that account seriously what comes to that gaur carcass, tiger and 13 men. There are many videos what comes to tiger dragging carcasses and in none they have showed ability to drag huge carcasses in the way like some old descriptions claim. Of course if wet grass and tiger drags something downhill, it might be difficult to drag that back uphill... 

In these things, what comes to animal strength I choose to believe what can be seen in countless video clips. And this performance by this bear was quite something. It practically lifted over half of that carcass and especially heavier part off the ground before it was turned. I´ve seen big cats to turn over carcasses, but never that big. And not in that way as this bear did. It didn´t just roll it over as I´ve seen some lions do.
Just out of curiosity, how many videos have you actually seen of Tigers dragging Gaur or Buffaloes?

The young male in Kanha drags a Gaur Cow fairly easy.
 
Quite many, and none gives that kind of impression as that old description. Here for instance moose are hunted every year and dragged in the woods by men to places in which they can be lifted to the trailer etc. And I don´t think, that any tiger would do better based on the video clips.

I mean, if 13 men can´t drag 500-700 kg, then we are talking about very small men who have no idea what they are doing :) And if we have a 1000 kg carcass, then I would love to see a video in which tiger tries to drag it even one meter. Unless in some very wet surface making it slide very easily. But then 13 men should be able to drag it too. That old account is just not something I can take seriously no matter how I try to imagine it :)