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

[GuateGojira]

The brown bear (Ursus arctos):

First of all, here is the pages from Gerard Wood (1978) in his exceptional book "Animal facts and feats":

*This image is copyright of its original author

*This image is copyright of its original author

*This image is copyright of its original author

*This image is copyright of its original author

Please, read it slowly, because it have a huge load of data that most be apreciated in each paragraph. A true treasure for bear-lovers.

*This image is copyright of its original author

Interestingly, the heaviest brown bear recorded by scientists is of 611 kg, according with this source. This is the heaviest brown bear that I have saw in all scientific literature. Now, check this support data:

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This is the original source of this record, and here we can clearly see that this 611 kg figure came from a bear weighed in the fall, which is a date when bears are very fat before the winter. The heaviest figure in spring is of 539.8 kg (or 540 kg, in round numbers, if you like). There is a significant reduction of fat, and this most be taken in count through comparisons

2. Schwartz et al. (2003; in Feldhamer et al. 2003), on his complete and authoritative chapter about the brown bear:

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Here, we can see that the variation in size of this bear is similar form to that of the tiger and jaguar. The largest bears are more than twice the size of the smaller ones. Take in count that here there is no data on the size of the bears of Eurasia, although it is said that those are smaller in the center of Asia and average to large (up to 320 kg, or 480 kg according with Wood (1978)) in Europe and Siberia. Finally, the best table that I have found on the bears of the Russian Far East, from the late Kucherenko (2003):

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The Siberian Tiger Project presented slightly different average figures (270 kg for males and 145 kg for females), but they don't present ranges nor sample size. I will try to get this data soon (I hope), and for those that could think that those figures are estimations, here you can see Linda, Bart and Dale (I think) with a large bear been weighed in Sikhote-Alin.

*This image is copyright of its original author

Finally, the Kamchatka bears are reported to be as large as the largest Kodiak bears, and the skulls seems to support that. However, at this day, I have not saw a single reliable weight to support this claim, just the same reports of bears of 500-700 kg from the same sources of the tigers of 300-350 kg, which is the old Russian literature.
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