Size

[brobear]

Jan 8, 2022 5:09:32 GMT -5 OldGreenGrolar said:

What is the average size and weight of all brown bears subspecies combine?

We just haven't been able to collect enough data for even a close estimation. Every brown bear population is different. Both DNA and food availability play a role. Also, to get a close average, we would not only need the ages and weights, but also the population numbers. ( IMO ) the grizzlies of Wyoming and Montana are probably average-sized brown bears. 

[OldGreenGrolar]

Jan 8, 2022 6:08:05 GMT -5 brobear said:

Jan 8, 2022 5:09:32 GMT -5 OldGreenGrolar said:

What is the average size and weight of all brown bears subspecies combine?

We just haven't been able to collect enough data for even a close estimation. Every brown bear population is different. Both DNA and food availability play a role. Also, to get a close average, we would not only need the ages and weights, but also the population numbers. ( IMO ) the grizzlies of Wyoming and Montana are probably average-sized brown bears. 

The most numerous brown bear subspecies in North America is the Peninsula Alaskan grizzly bear.

[brobear]

Jan 8, 2022 6:42:56 GMT -5 OldGreenGrolar said:

Jan 8, 2022 6:08:05 GMT -5 brobear said:

We just haven't been able to collect enough data for even a close estimation. Every brown bear population is different. Both DNA and food availability play a role. Also, to get a close average, we would not only need the ages and weights, but also the population numbers. ( IMO ) the grizzlies of Wyoming and Montana are probably average-sized brown bears. 

The most numerous brown bear subspecies in North America is the Peninsula Alaskan grizzly bear.

This is true. But, there are also brown bears smaller than inland grizzlies, including the barren ground grizzly, The Himalayan red bear, the Tibetan blue bear, the Gobi bear, and the Syrian brown bear. How they would average out is guesswork.

[theundertaker45]

This is a huge male Alaskan brown bear filmed by Andreas Kieling and his crew; he has been travelling Alaska for the past 30 years and spent some years trying to reach out to the gigantic Alaskan brown bears pictured in old hunting journals. After a long time having no luck, he came eye to eye with this male digging out clams at a muddy bay; per his personal comments this brute fulfilled his criterias and he initially couldn't contain his excitement filming the bear which resulted in the bear walking towards him. Luckily he didn't have any interest and went back to his clams; in his opinion this male bear would have been a legit 1500 pounder (coming from a man that has 30 years of experience filming and researching North America's bears).

[brobear]

Reply #383: Wish we had some I.D. on this possible replacement of Van. From this photo, he still looks quite young with no visible battle scars. If so, he might still have some growing to do.

[hwn]

很难给出一个具体的值来承受大小。它们不像大猫。

Attachments:

[theundertaker45]

World Records by Weight (Ursus arctos; SH and HB estimated):

- Gobi Bear (Ursus arctos gobiensis) - 85cm SH, 146.6cm HB (138kg; Gobi Bear Conservation, 2010)
- Syrian Brown Bear (Ursus arctos syriacus) - 94.5cm SH, 163.2cm HB (190kg; Heptner & Naumov, 1998)
- Interior Grizzly Bear (Ursus arctos horribilis) - 117cm SH; 200cm HB (350kg; Stenhouse, per.com.)
- Ussuri Brown Bear (Ursus arctos lasiotus; Russian Mainland) - 117.3cm SH, 202.4cm HB (363kg; Seryodkin et al., 1999)
- Eurasian Brown Bear (Ursus arctos arctos) - 128.9cm SH, 222.2cm HB (480kg; Wood & Gerald, 1983)
- Ussuri Brown Bear (Ursus arctos lasiotus; Hokkaido) - 132.2cm SH, 228.2cm HB (520kg; Moriwaki et al., 2017)
- Kamchatka Brown Bear (Ursus arctos beringianus/piscator) - 144.9cm SH; 250.2cm HB (685kg; Wood & Gerald, 1983)
- California Grizzly (Ursus arctos californicus; Nevada Range) - 145.8cm SH; 251.6cm HB (697kg; Wood & Gerald, 1983)
- Alaska Peninsula Brown Bear (Ursus arctos gyas) - 147.9cm SH; 255cm HB (726kg; Wood & Gerald, 1983)
- Kodiak Brown Bear (Ursus arctos middendorffi) - 149.5cm SH; 257.9cm HB (751kg; Wood & Gerald, 1983)
- Steppe Brown Bear (Ursus arctos priscus) - 164.4cm SH; 283.8cm HB (1000kg; Marciszak et al., 2019)



I based all of the calculations on Blanchard's data which contains over 60 male grizzly bears; so it should be as accurate as it gets; SH means shoulder height and HB refers to head-body length (measured in a straight line).

[brobear]

Metric conversion:
- Gobi Bear - 138 kg = 304.24 pounds.
- Syrian Brown Bear - 190 kg = 418.88 pounds.
- Interior Grizzly - 350 kg = 771.62 pounds.
- Ussuri Brown Bear - 363 kg = 800.28 pounds.
- Kamchatka Brown Bear - 685 kg = 1,510.17 pounds.
- California Grizzly - 697 kg = 1,536.62.
- Alaska Peninsula Brown Bear - 726 kg = 1,600.56 pounds.
- Kodiak Brown Bear - 751 kg = 1,655.67 pounds.
- Steppe Brown Bear - 1,000 kg = 2,204.62 pounds.

[brobear]

Brown Bear - www.inaturalist.org/guide_taxa/889098

The size of brown bears is the most variable of modern bears. The typical size depends upon which population it is from, and most accepted subtypes vary widely in size. This is in part due to sexual dimorphism, as male brown bears average at least 30% larger in most subtypes. Individual bears also vary in size seasonally, weighing the least in spring due to lack of foraging during hibernation, and the most in late fall, after a period of hyperphagia to put on additional weight to prepare for hibernation. Therefore, a bear may need to be weighed in both spring and fall to get an idea of its mean annual weight.

The normal range of physical dimensions for a brown bear is a head-and-body length of 1.4 to 2.8 m (4 ft 7 in to 9 ft 2 in) and a shoulder height of 70 to 153 cm (2 ft 4 in to 5 ft 0 in). The tail is relatively short, as in all bears, ranging from 6 to 22 cm (2.4 to 8.7 in) in length. The smallest brown bears, females during spring among barren-ground populations, can weigh so little as to roughly match the body mass of males of the smallest living bear species, the sun bear (Helarctos malayanus), while the largest coastal populations attain sizes broadly similar to those of the largest living bear species, the polar bear. Interior brown bears are generally smaller than is often perceived, being around the same weight as an average Southern African lion, at an estimate average of 180 kg (400 lb) in males and 135 kg (298 lb) in females, whereas adults of the coastal populations weigh about twice as much. The average weight of adult male bears from 19 populations, from around the world and various subspecies (including both large and small bodied subspecies), was found to 217 kg (478 lb) while adult females from 24 populations were found to average 152 kg (335 lb).

Brown bear size, most often measured in body mass, is highly variable and is correlated to extent of food access. Therefore, bears who range in ecozones that include have access to openings, cover and moisture or water tend to average larger whereas those bears that range into ecozones with enclosed forested areas or arid, sparsely vegetated regions, both of which tend to be sub-optimal foraging habitat for brown bears, average smaller. The brown bear in northern Europe (i.e. Scandinavia, eastern Europe, western Russia), Yellowstone National Park or interior Alaska seasonally weigh on average between 115 and 360 kg (254 and 794 lb), from mean low adult female weights in spring to male bear mean high weights in fall. Bears from the Yukon Delta, interior British Columbia, Jasper National Park and southern Europe (i.e. Spain, the Balkans) can weigh from 55 to 175 kg (121 to 386 lb) on average. These mass variations represent only two widespread subspecies, the grizzly bear in North America, and the Eurasian brown bear in Europe. Due to the lack of genetic variation within subspecies, the environmental conditions in a given area likely plays the largest part in such weight variations.

The grizzly is especially variable in size, as grizzlies from the largest populations, i.e. interior Alaska, with the heaviest weights recorded in Nelchina, Alaska, nearly three times heavier in males than the smallest grizzlies from Alberta, Canada's Jasper National Park. Between the sexes, the grizzlies of Nelchina average around 207 kg (456 lb), whereas the Jasper grizzlies averaged about 74 kg (163 lb). The enclosed taiga habitat of Jasper presumably is sub-optimal foraging habitat for grizzlies, requiring them to range widely and feed sparsely, thus reducing body weights and putting bears at risk of starvation, while in surfaces areas in the tundra and prairie are apparently ideal for feeding. Even elsewhere in the Alberta province, weights averaging more than twice those of Jasper grizzlies have been recorded. A gradual diminishment in body size is noted in grizzly bears from the sub-Arctic zone, from the Brooks Range to the Mackenzie Mountains, presumably because food becomes much sparser in such regions, although perhaps the most northerly recorded grizzly bears ever, in the Northwest Territories, was a large and healthy male weighing 320 kg (710 lb), more than twice as much as an average male weighs near the Arctic Circle. Data from Eurasia similarly indicates a diminished body mass in sub-Arctic brown bears, based on the weights of bears from northern Finland and Yakutia.

Head-and-body length in grizzly bears averages from 1.8 to 2.13 m (5 ft 11 in to 7 ft 0 in) while in Eurasian brown bears it similarly averages from 1.7 to 2.1 m (5 ft 7 in to 6 ft 11 in). Adult shoulder height averaged 95.2 cm (3 ft 1 in) in Yellowstone (for any bear measured five or more years old) and a median of 98.5 cm (3 ft 3 in) (for adults only 10 or more years old) in Slovakia. Standing on its hindlegs, a posture only assumed occasionally, typically sized brown bears can reportedly range from 1.83 to 2.75 m (6 ft 0 in to 9 ft 0 in) in standing height. Exceptionally large inland specimens have been reported in several parts of North America, Europe, Russia and even Hokkaido. The largest recorded grizzlies from Yellowstone and Washington state both weighed approximately 500 kg (1,100 lb) and eastern European bears have been weighed in Slovakia and Bulgaria of up to 400 kg (880 lb), about double the average weight for male bears in these regions. Among the grizzly and Eurasian brown bear subspecies, the largest reportedly shot from each being 680 kg (1,500 lb) and 481 kg (1,060 lb), respectively. The latter bear, from western Russia, reportedly measured just under 2.5 m (8 ft 2 in) in head-and-body length.

In Eurasia, the size of bears roughly increases from the west to the east, with the largest bears there native to eastern Russia. Even in the nominate subspecies size increases in the eastern limits, with mature male bears in Arkhangelsk Oblast and Bashkortostan commonly exceeding 300 kg (660 lb). Other bears of intermediate size may occur in inland populations of Russia. Much like the grizzly and Eurasian brown bear, populations of the Ussuri brown bear (U. a. lasiotus) and the East Siberian brown bear (U. a. collaris) may vary widely in size. In some cases, the big adult males of these populations may have matched the Kodiak bear in size. East Siberian brown bears from outside the sub-Arctic and mainland Ussuri brown bears average about the same size as the largest-bodied populations of grizzly bear, i.e. those of similar latitude in Alaska, and have been credited with weights ranging from 100 to 400 kg (220 to 880 lb) throughout the seasons. On the other hand, the Ussuri brown bears found in the insular population of Hokkaido are usually quite small, usually weighing less than 150 kg (330 lb), exactly half the weight reported for male Ussuri brown bears from Khabarovsk Krai. This is due presumably to the enclosed mixed forest habitat of Hokkaido. A similarly diminished size has been reported in East Siberian brown bears from Yakutia, as even adult males average around 145 kg (320 lb), thus about 40% less than the average weight of male bears of this subtype from central Siberia and the Chukchi Peninsula.

In linear measurements and mean body mass, several subspecies may vie for the title of smallest subtype, although thus far their reported body masses broadly overlaps with those of the smaller-bodied populations of Eurasian brown and grizzly bears. Leopold (1959) described the now extinct Mexican grizzly bear that, according to Rausch (1963), as the smallest subtype of grizzly bear in North America, although the exact parameters of its body size are not known today. Bears from the Syrian (U. a. syriacus) subspecies will reportedly weigh around 100 to 160 kg (220 to 350 lb) in adulthood. The Himalayan brown bear (U. a. isabellinus) is another rival for smallest subspecies, in Pakistan this subtype averages about 70 kg (150 lb) in females and 135 kg (298 lb) in males. Himalayan brown bear females were cited with an average head-and-body length of merely 1.4 m (4 ft 7 in). Brown bears of the compact Gobi Desert population, which is not usually listed as a distinct subspecies in recent decades, weigh around 90 to 138 kg (198 to 304 lb) between the sexes, so are similar in weight to bears from the Himalayas and even heavier than grizzlies from Jasper National Park. However, the Gobi bear has been reported to measure as small as 1 m (3 ft 3 in) in head-and-body length, which if accurate would make them the smallest known brown bear in linear dimensions. These smallest brown bear subtypes are characteristically found in "barren ground" type habitats, i.e. sub-desert in bears from the Syrian and Gobi subtype and arid alpine meadow in Himalayan bears.

The largest subspecies are the Kodiak bear (U. a. middendorffi) and the questionably distinct peninsular or coastal brown bear (U. a. gyas). Also the extinct California grizzly bear (U. a. californicus) was rather large. Once mature, the typical female Kodiak bear can range in body mass from 120 to 318 kg (265 to 701 lb) and while from sexual maturity onward male ranges from 168 to 675 kg (370 to 1,488 lb). According to Guinness Records the average male Kodiak bear is 2.44 m (8 ft 0 in) in total length (head-to-tail) and has a shoulder height of 1.33 m (4 ft 4 in). When averaged between their spring low and fall high weights from both localities, males from Kodiak island and coastal Alaska weighed from 312 to 389 kg (688 to 858 lb) with a mean body mass of 357 kg (787 lb) while the same figures in females were 202 to 256 kg (445 to 564 lb) with a mean body mass of 224 kg (494 lb). By the time they reach or exceed eight to nine years of age, male Kodiak bears tend to be much larger than newly mature 6-year-old males, potentially tripling their average weight within three years’ time, and can expect to average between 360 and 545 kg (794 and 1,202 lb). The reported mean adult body masses for both sexes of polar bear are very similar to the peninsular and Kodiak bears. Due to their roughly corresponding body sizes, the two subtypes and the species can both legitimately be considered the largest living member of the bear family Ursidae and largest extant terrestrial carnivores. The largest widely accepted size for a wild Kodiak bear, as well as for a brown bear, was for a bear killed in English Bay on Kodiak Island in fall 1894 as several measurements were made of this bear, including a body mass of 751 kg (1,656 lb), and a hind foot and a voucher skull were examined and verified by the Guinness Book of World Records. Claims have been made of larger brown bears, but these appear to be poorly documented and unverified and some, even if recited by reputable authors, may be dubious hunters' claims.

The largest variety of brown bear from Eurasia is the Kamchatka brown bear (U. a. beringianus). In the Kamchatka brown bear in past decades, old males have been known to reach body mass of 500–685 kg (1,102–1,510 lb) by fall, putting the subtypes well within Kodiak bear sizes and leading it to be considered the largest of the extant Russian subtypes. However, a diminishment in body size of U.a. berigianus has been noted, mostly likely in correlation with overhunting. In the 1960s and 1970s, most adult Kamchatka brown bears weighed merely between 150 and 285 kg (331 and 628 lb), however, mean weights of mature male bears have been reported as averaging 350 to 450 kg (770 to 990 lb) in 2005.

[Deleted]

Sept 19, 2021 11:06:58 GMT -5 theundertaker45 said:

@shadow

As we were talking about shoulder heights some time ago, I decided to give something a try. There is a study from Blanchard on the dimensions of Yellowstone grizzlies in the late 20th century; the sample of adult males (5y+) averaged 193kg and the shoulder height measured in a proper way was 95cm. The bears used for the sample were predominantly captured in summer, so not really in fat condition. Coincidentally there is a study on Alaskan Peninsula brown bears by Glenn with a fairly big sample size just like the Yellowstone sample; the average weight for the adult males (5.5y+) was ~357kg in this case and all of the bears were also captured during August.

Using the proportions of a Yellowstone grizzly as a template (95cm tall and 193kg) I am able to determine the theoretical shoulder height of those Alaskan brown bears assuming that both groups share a similar bulk. 

193/0.95² = 213.850415512
357/x² = 213.850415512
x = ~1.29

So with this rough estimation I'd get a shoulder height of  around 129cm for an average male Alaskan Peninsula brown bear; your thoughts? For me it would seem reasonable as we were talking about a maximum figure of 150cm.

It seems reasonable to have a 129cm shoulder height for an average fully grown alaskan brown bear. Just to be sure: why you square your coefficient 0.95?
Do you have a link to the Blanchard study please?
I appreciate your attempt to provide an answer about the shoulder height of brown bears but maybe your calculation is too simple. Do you know more sophisticated method to evaluate the shoulder height of brown bears please?
A shoulder height of 150cm is enormous for a carnivore, do you realize this   ? I don't tell that it is not possible, i think that only freak specimens of kodiak bears could atteign such size maybe, i am not sure, it must be exceptional.
Thank you.

[theundertaker45]

@hibernours

This is an old calculation; it's not up-to-date. I'll revaluate it here; Blanchard's database on Yellowstone grizzlies gives us a HBL over the curves of 197cm and a SH of 96cm based on 23 male grizzlies aged 5y or older (in all of those 23 individuals both values have been taken at the same time). Five fully grown Alaskan Peninsula brown bears in Glenn's work were 254cm over the curves. So what is the shoulder height of the Alaskan bears? It's probably ~124cm assuming the ratio is the same as in the Yellowstone grizzlies. I nowadays prefer to go by length measurements than weight as the dimensions are defined by height/length. In hunting records there are mentiongs of huge 700kg Alaskan/Kodiak bears measuring well over 300cm over the curves, so in this case a SH of 150cm is definitely possible for the absolute largest brown bears.

[brobear]

Also note, a male brown bear is not a full-grown bear until he reaches 9 years old. In fact, even after this he will continue to grow until he is roughly around 15 years old. I have read several of Doug Peacock books on the grizzlies of Montana. He considers a full-grown male grizzly to be 10 years old and up.
So, to find the average size of a brown bear, we should do the math using only male bears from 9 years old and up.

[OldGreenGrolar]

The paws of the brown bear are quite large. The rear feet of adult bears have been found to typically measure 21 to 36 cm (8.3 to 14.2 in) long, while the forefeet tend to measure about 40% less in length. All four feet in average sized brown bears tend to be about 17.5 to 20 cm (6.9 to 7.9 in) in width. In large coastal or Kodiak bear males, the hindfoot may measure up to 40 cm (16 in) in length, 28.5 cm (11.2 in) in width, while outsized Kodiak bears having had confirmed measurements of up to 46 cm (18 in) along their rear foot. Brown bears are the only extant bears with a hump at the top of their shoulder, which are made entirely of muscle, this feature having developed presumably for imparting more force in digging, which is habitual during foraging for most bears of the species and also used heavily in den construction prior to hibernation.


www.inaturalist.org/guide_taxa/889098#:~:text=The%20paws%20of%20the%20brown,to%207.9%20in)%20in%20width.

[brobear]

Some good worthwhile information here OldGreenGrolar. Thumbs up.

[Deleted]

In a paper on Ursus arctos priscus, there is this statement: The world record Kodiak bear killed in 1948 has the skull of 487mm long (Couturier, 1954).
Do you know if there are larger skulls of modern brown bears?

[theundertaker45]

@hibernours

The biggest modern brown bear skull in terms of greatest length was 503mm; collected from a bear in Port Heiden but it isn't the world record. The world record brown bear skull is from a Kodiak bear that wasn't exactly that long (it was much longer than average but there have been many longer skulls) but it was extremely broad (I think over 320mm).

[Deleted]

May 23, 2023 3:04:07 GMT -5 theundertaker45 said:

@hibernours

The biggest modern brown bear skull in terms of greatest length was 503mm; collected from a bear in Port Heiden but it isn't the world record. The world record brown bear skull is from a Kodiak bear that wasn't exactly that long (it was much longer than average but there have been many longer skulls) but it was extremely broad (I think over 320mm).

Hum hum. I trust you but i would like to have the source for the value of 503mm you provide please. Ursus arctos priscus seems to have been a very big and powerful bear but there is a little problem: in the papers i have about Ursus arctos priscus, there is no skull reaching a length of 503 mm. So to my knowledge, no Ursus arctos priscus had a skull larger than this one you have provided (503mm). So my question is: considering the fact that no modern brown bear can reach a mass of 1000kg, how can we tell that Ursus arctos priscus was larger than large modern brown bears...?
Maybe there are some bones not presented in scientific papers which are larger, it is a possibily but can someone give me a confirmation?
The width of 320 mm you have provided is absolutely huge, it is really impressive. But some short faced bears had a skull larger than this one.
Thanks.

[brobear]

The size of brown bears, from biggest to the smallest listed. Some are not precise but are grouped among those of similar size:

1- Kodiak bear.
2- Alaskan Peninsula Brown Bear
3- Kamchatka brown bear
4- Ussuri brown bear
5- Hokkaido brown bear
6- Eurasian brown bear
7- Mongolian brown bear
8- East Siberian brown bear
9- Sitka brown bear
________________

10- (inland) Grizzly
11- Marsican brown bear
12- Tibetan brown bear
13- Gobi bear
14- Himalayan brown bear 
 
*Note; several years ago, I was surprised to learn that the inland grizzly is actually among the smaller brown bear subspecies. However, historically, there were some huge grizzlies living on the Great Plains and in California. 

[theundertaker45]

I found a document that hasn't been shared before here I think; a sample of 11 selectively picked prime male Kodiak bears averaged a spring weight of 937lbs or 425kg. The largest of this sample is estimated to have weighed over 1500lbs or 680kg in autumn; also I have found another source of an Alaskan Peninsula brown bear being weighed at 1275lbs in spring which would be close to 600kg. If you know bears and the weight ratios for spring -> autumn those males approach the old hunting records.

"Obtaining weights of large bears is difficult. Relatively few large Kodiak males have been
captured for research projects and even then the equipment needs and difficult terrain
made weighing impractical. However, I gathered information from bear guides and
Kodiak NWR files for hunter-killed bears that were cut into manageable portions and
weighed with hand scales. I obtained weights for 21 males. Because I was only
interested in large bears, I limited the sample to males weighing more than 800 lbs in
spring and 1000 lbs in fall. For each bear I added 25 lbs to account for blood and other
fluids lost in the weighing process.
Bears reach maximum size in fall just prior to the winter denning period. Weights of
three males taken in fall hunts averaged 1277 lbs (1078-1407 range). Eleven males taken
in spring hunts averaged 937 lbs (803-1215 range). Because bear weights increase at
least 25% from spring to fall, I adjusted the spring weights accordingly to estimate what
those bears would have weighed the previous fall. The estimated fall weights ranged
from 1004 to 1519 lbs and averaged 1171. The three largest weight estimates were
1245, 1483 and 1519 lbs. It’s interesting to note that an exceptionally large female taken
on a fall hunt weighed 767 lbs.
In most cases, the weights reported above were obtained because the guides and
biologists recognized that the bears were unusually large. Thus, they probably represent
the upper limits of male weights in spring and fall. The results indicate that the biggest
Kodiak bears can grow to just over 1500 lbs. I extend thanks to bear guides Joe Want
and Dick Rohrer, who provided most of the above information."

assets.website-files.com/63d884c1cead0e59c3a114ea/63d9d5d45717bb783b31599c_KBBT%202013%20Annual%20Report.pdf

[brobear]

Some very valuable information there "Taker. When you say (quote), "I found a document that hasn't been shared before here I think; a sample of 11 selectively picked prime male Kodiak bears averaged a spring weight of 937lbs or 425kg."

I take it that all 11 of these male Kodiak bears were 10 years old or better. At least no bear under the age of 9.