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The "King" of the bears - comparison between the Polar bear and the Brown bear - Printable Version

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RE: The "King" of the bears - comparison between the Polar bear and the Brow... - brotherbear - 12-15-2018

(12-15-2018, 01:05 AM)Panther Wrote:
(12-14-2018, 08:02 PM)brotherbear Wrote: Still no average weights found for 9+ year old male Kodiak bear. 
In fact, neither have we an average weight posted for 9+ year old male polar bear.
And as Shadow said: But it is quite common agreement, that bear aged 9-10 years old can be considered as fully grown, even though they gain more weight after that too.

Well I remember you said 9 year old is fully grown here...
https://wildfact.com/forum/topic-bear-anatomy?pid=63729#pid63729

But now you asking 9+(10) year old individuals? 

Maximum isn't average weight. Individuals vary, not all brown bears reach and surpass 1300lb mark at 14 years age. That based on individual. 


The study I posted above is logically based on no less than 8 year old individuals. 
Show me a research, study or an expert claiming 8 year old individual isn't fully grown? 

I'm not trying to be rude, but you need to back up something on your side too. Because I already shown that on average male Brown bears reaching their full size in almost all dimensions at 6 years. And already shown that Alaskan Brown bears reach sexual maturity at age 6. So, don't the two years time is enough for a brown bear to reach it's full size in all dimensions and weight?

The polar bear is the biggest heaviest bear living on earth today. I absolutely agree. 
Panther, by 9+ year old bears I mean only bears 9 years old and above should be considered as full-grown.


RE: The "King" of the bears - comparison between the Polar bear and the Brow... - Shadow - 12-15-2018

(12-15-2018, 08:28 AM)GuateGojira Wrote: So, the weight of 611 kg from the largest Alaska bear in scientific records (that I have saw) is a "fat" weight, while the figure of 540 kg is a "lean" weight, which is more reliable, am I correct?

With the maximum average at about 379 kg for the largest brown bear population, it seems clear that the winner for the title of the "king" of bears is still  the polar bear, with an average weight of 489 kg at Hudson Bay (94 males over 5 years old) and a maximum weigh of 699 kg recorded in Alaska (some males were to heavy to be lift and were estimated to weight 800 kg).

Did polar bears also suffer from the "age and season" issue like the brown bears? I think is a relevant question.

That 540 kg is spring weight and looks like to be different bear, than that 611 kg bear obviously. Reasoning for this is, that it is commonly agreed, that Kodiak bears (and other brown bears) gain weight from spring to autumn at least 20-30 %.

Then again there is in one chart mentioned, that reserchers used multiplier 1,24 to make spring weighings of male bears comparable with other weighings.

With that multiplier we get estimation, that 540 kg spring weight means about 670 kg bear on autumn. Then again with same calculation reversed that 611 kg autumn weight would be about 493 kg spring weight. If we assume, that scientist know what they are doing when creating multipliers :)

What comes to brown bear populations and subspecies, that is one issue. But what comes to polar bears and Kodiak bears, I think, that it doesn´t matter when Kodiak bears are weighed (or any other brown bear), because fat layer is natural part of them and same thing is with polar bear. Polar bears just wear it all the time. So I think, that it would be quite unfair to compare only spring weighed brown bears, when comparing to animal having even up to 50% of their body mass fat in layer 3-4,5 inches thick.

Here is one link: http://icestories.exploratorium.edu/dispatches/how-fat-is-a-polar-bear/index.html

Still polar bear is bigger and heavier as far as I know. But when making comparison between polar bears and brown bears, I think that then weighing time of brown bear is not as relevant as it is when comparing brown bear subspecies/populations between each others.

Main thing of course is, that we know and realize relevant things to be able to do fair and reasonable comparisons.


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - brotherbear - 12-15-2018

I hadn't given that any thought, but When comparing a Kodiak bear with a polar bear, the best time to weigh a Kodiak bear is late Autumn when his fat ratio is closer to the polar bear's. Of course, while the size difference between Kodiak bears and polar bears is not a tremendous difference, as a species in general, the polar bear is without contest much bigger than a typical brown bear - Ursus arctos. 
 
Edit and add: About ages of brown bears added into the average size for full-grown males - eight is less than nine.


RE: The "King" of the bears - comparison between the Polar bear and the Brow... - Shadow - 12-16-2018

(12-15-2018, 08:49 PM)Shadow Wrote:
(12-15-2018, 08:28 AM)GuateGojira Wrote: So, the weight of 611 kg from the largest Alaska bear in scientific records (that I have saw) is a "fat" weight, while the figure of 540 kg is a "lean" weight, which is more reliable, am I correct?

With the maximum average at about 379 kg for the largest brown bear population, it seems clear that the winner for the title of the "king" of bears is still  the polar bear, with an average weight of 489 kg at Hudson Bay (94 males over 5 years old) and a maximum weigh of 699 kg recorded in Alaska (some males were to heavy to be lift and were estimated to weight 800 kg).

Did polar bears also suffer from the "age and season" issue like the brown bears? I think is a relevant question.

That 540 kg is spring weight and looks like to be different bear, than that 611 kg bear obviously. Reasoning for this is, that it is commonly agreed, that Kodiak bears (and other brown bears) gain weight from spring to autumn at least 20-30 %.

Then again there is in one chart mentioned, that reserchers used multiplier 1,24 to make spring weighings of male bears comparable with other weighings.

With that multiplier we get estimation, that 540 kg spring weight means about 670 kg bear on autumn. Then again with same calculation reversed that 611 kg autumn weight would be about 493 kg spring weight. If we assume, that scientist know what they are doing when creating multipliers :)

What comes to brown bear populations and subspecies, that is one issue. But what comes to polar bears and Kodiak bears, I think, that it doesn´t matter when Kodiak bears are weighed (or any other brown bear), because fat layer is natural part of them and same thing is with polar bear. Polar bears just wear it all the time. So I think, that it would be quite unfair to compare only spring weighed brown bears, when comparing to animal having even up to 50% of their body mass fat in layer 3-4,5 inches thick.

Here is one link: http://icestories.exploratorium.edu/dispatches/how-fat-is-a-polar-bear/index.html

Still polar bear is bigger and heavier as far as I know. But when making comparison between polar bears and brown bears, I think that then weighing time of brown bear is not as relevant as it is when comparing brown bear subspecies/populations between each others.

Main thing of course is, that we know and realize relevant things to be able to do fair and reasonable comparisons.

Hmmm.... I made here a mistake, it has been some time since last time looking closer to polar bears. But even though they don´t hibernate (except pregnant females), they also have variation in weight and can lose a lot of fat reserves when sea is unfrozen and they can´t hunt seals at least in some areas. So also with polar bears it is important to know, that when they have been weighed and in which condition. Complex animals... :)


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - Panther - 12-16-2018

(12-15-2018, 04:54 PM)brotherbear Wrote: The polar bear is the biggest heaviest bear living on earth today. I absolutely agree. 
Panther, by 9+ year old bears I mean only bears 9 years old and above should be considered as full-grown.

Well I think the bears above nine are post prime, aren't they?

I guess the chart you posted about averages is right, 8-9 year old are fully grown. Which is why that's the last age class of taking averages...

(12-15-2018, 09:14 PM)brotherbear Wrote: I hadn't given that any thought, but When comparing a Kodiak bear with a polar bear, the best time to weigh a Kodiak bear is late Autumn when his fat ratio is closer to the polar bear's. Of course, while the size difference between Kodiak bears and polar bears is not a tremendous difference, as a species in general, the polar bear is without contest much bigger than a typical brown bear - Ursus arctos. 
 
Edit and add: About ages of brown bears added into the average size for full-grown males - eight is less than nine.

I asked you the proof like a study or a expert quote of 8 year old means not full-grown. 

I already proven that Brown bears reach their full size in almost all dimensions at 6 years on average. The two years gap is enough for a bear to reach its full size.


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - brotherbear - 12-16-2018

http://shaggygod.proboards.com/  
   
Grizzly Bear Anatomy:  Males attained full size in 7 of 11 body measurements by age 6 and in all 11 by age 9.


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - Panther - 12-16-2018

(12-16-2018, 04:02 PM)brotherbear Wrote: Grizzly Bear Anatomy:  Males attained full size in 7 of 11 body measurements by age 6 and in all 11 by age 9.

That's what I'm talking about! It's not "9+", but "9".
I already know this, it's from the study of 300kgs average chart, I posted in the beginning. 

So, 8 year(logically) old Brown bears got the average of 700lbs means 9 year old Brown bears can get average upto 800lbs.

Remember the more bears you weigh, you'll get less than 835lbs by your chart..


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - brotherbear - 12-17-2018

Remember the more bears you weigh, you'll get less than 835lbs by your chart.. 
 
That comment makes no sense. The more male brown bears that are weighed from 9 years old and up, the closer to the truth you come when seeking an average weight. The biggest bears will not likely even be weighed. A brown bear living where hunting is allowed and lives to be upwards to 1400 pounds is a smart elusive bear. To be quite honest, I doubt that average weights given are ever truly accurate. 


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - Panther - 12-17-2018

(12-17-2018, 04:10 AM)brotherbear Wrote: That comment makes no sense. The more male brown bears that are weighed from 9 years old and up, the closer to the truth you come when seeking an average weight. The biggest bears will not likely even be weighed. A brown bear living where hunting is allowed and lives to be upwards to 1400 pounds is a smart elusive bear. To be quite honest, I doubt that average weights given are ever truly accurate. 

The chart you posted given the age class only upto 8-9year old. That means it's the right age class to verify brown bears as adults. So forget about "9+".

The five Brown bears giving some misleading figure, the more bears you weigh the average would likely be 800lbs. 

And how can you sure that larger Brown bears aren't weighed. The largest one in the average is 1150lbs, that's not "small" and you can't sure all Brown bears reach and surpass 1300lb figure. Because individuals vary.

Also what's wrong with the average of 800lbs? It's the most likely figure. Because in the chart given 300kgs average for Kodiak bears, the Alaska peninsula Brown bears have an average of 389kgs with a maximum of 448kgs based on 5. Which is misleading. But on other study, it gives 357kgs based on 21 individuals. Which is why, I'm telling the more bears you weigh the average would be less than 835lbs and most likely 800lbs or even less.
But I guess It's 800lbs...


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - brotherbear - 12-17-2018

That chart shows Alaskan peninsula brown bears are larger than Kodiak bears - obviously using sub-adult Kodiak bears in study ( below age 9 ).


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - Panther - 12-17-2018

(12-17-2018, 12:15 PM)brotherbear Wrote: That chart shows Alaskan peninsula brown bears are larger than Kodiak bears - obviously using sun-adult Kodiak bears in study ( below age 9 ).

They used kodiak bears started at age of 8 years (logically). Of course below nine, but they gave 700lbs average.

So 9 year old individuals may have average of 800lbs, which is larger than 787lbs of Alaska peninsula Brown bears.

Would you agree with this?


RE: The "King" of the bears - comparison between the Polar bear and the Brow... - Shadow - 12-17-2018

Here are three charts concerning brown bears. One might notice in all three something surprisingly in common..... if paying attention Wink  Someone might even think, that what the ****? If paying attention and taking some time to think..... Grin


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - Panther - 12-17-2018

(12-17-2018, 12:58 PM)Shadow Wrote: Here are three charts concerning brown bears. One might notice in all three something surprisingly in common..... if paying attention Wink  Someone might even think, that what the ****? If paying attention and taking some time to think..... Grin

The first chart is eleminated already for having sub adult Brown bears. But it's useful to describe the age of Brown bears in second chart.


But the second and third charts are the only charts we have to discuss about!


RE: The "King" of the bears - comparison between the Polar bear and the Brow... - Shadow - 12-17-2018

(12-17-2018, 12:58 PM)Shadow Wrote: Here are three charts concerning brown bears. One might notice in all three something surprisingly in common..... if paying attention Wink  Someone might even think, that what the ****? If paying attention and taking some time to think..... Grin

I add that much, that there are things to check and it takes a little bit time so at this point I don´t write more. But as said, in all three charts can be found something in common in a way, that it creates questions. At least for me :)


RE: The "King" of the bears - comparison between the Polar bear and the Brown bear - brotherbear - 12-18-2018

A relatively accurate average weight for fully mature male Kodiak bears can not be found without proper - improved data. Research.