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11-20-2020, 03:15 PM( This post was last modified: 05-12-2021, 09:02 AM by peter )
ON THE SIZE OF AMUR TIGERS AND USSURI BROWN BEARS - PART I - RECENT INFORMATION
a - Introduction
A few days ago, our member 'Nyers' informed us about a new book on Amur tigers ('The uncrowned lord of the taiga') in the thread 'Amur tigers' (post 646). The online version (in Russian) is already available. The English translation will be published next year. The book, written by Yuri Dunishenko and Sergey Aramilev (General Director of the Amur Tiger Center) and published by the Amur Tiger Center, is based on recent scientific information. Both are undisputed authorities on wild Amur tigers, meaning the book is a 'must' for those interested in Amur tigers.
The title of the new book no doubt will result in a few questions. Amur tigers and Ussuri brown bears more or less compare in head and body length, but Ussuri brown bears are more robust and heavier animals. For many, the question is who dominates who.
Reliable information says male Amur tigers in particular hunt Ussuri brown bears up to the size of, and including, adult females. Some male Ussuri bears, and non-hibernating bears (also known as 'Schatuns' or 'Satellite' bears) in particular, however, follow, and sometimes hunt tigresses with cubs and immature tigers. It has to be added, however, that no such incidents have been recorded in the period 1992-2020.
No incidents apart from two, I mean. One of them was an immature tigress found in the snow. Researchers arrived too late to get to solid conclusions. They assumed she had been killed by a bear, but the evidence they presented was inconclusive. Nearly all tigers killed by brown bears are eaten, but this tigress wasn't. In the period she was found, a number of Amur tigers had been affected by a disease. Some of those affected showed unusual behaviour. It could be she was one of them.
There's no information about the second incident, but adult tigress 'Vera', also allegedly killed by a bear, is mentioned in an article about the (disadvantages of) Aldrich footsnares. The article, first published on a Russian forum, will be discussed in the near future.
Interactions between males seem to be few. What we know, suggests male tigers and male brown bears avoid each other. A few incidents between large male brown bears and young adult male tigers have been described by Sysoev and Rukovsky. Their observations are considered as reliable, but most other stories about interactions between males of both species, as far as I know, have been dismissed.
My guess is the situation won't change any time soon. The Russian Far East is a large and almost empty region. Most interactions between tigers and bears go unnoticed, that is. The only way to collect good information is to collar adult tigers and bears and monitor their behaviour for a prolonged period of time.
b - A new document on Ussuri brown bears
Less than a year ago, a new document on Ussuri brown bears written by Seryodkin (IV), Kostyria (YK), Goodrich (JM) and Petrunenko (YK) was published in the Journal of Siberian Federal University Biology 12(4), Dec. 2019 (pp. 366-384): 'Space use by brown bears (Ursus arctos) in the Sichote-Alin'. It has an interesting table on the size of Ussuri brown bears captured in the period 1993-2001.
The abstract is in Russian and in English. Here's the scan of the English translation:
*This image is copyright of its original author
Here's a scan of the table mentioned above:
*This image is copyright of its original author
I used the table to get to 2 others: a table on adult male bears and a table on adult female brown bears. Bears III (a 2-3 year old male), IX (a 4-year old female) and XV (a 3-year old female) in the table above were not used for the tables on account of their age (immature).
Here's the table on adult females. They averaged 181,17 cm in total length (most probably measured 'over curves') and 163,75 kg (361 pounds). The sample, however, is very small:
*This image is copyright of its original author
And here's the table on adult males. They averaged 211,63 cm in total length (most probably measured 'over curves') and 257,50 kg (almost 568 pounds). The heaviest male (No. V) was weighed in May. It's very likely he would have been over 400 kg. in late autumn:
*This image is copyright of its original author
The difference between young adults (5-8 years of age) and mature adults (9 years and over) is pronounced. Mature bears are not longer, but heavier. In males in particular, the difference is outspoken. Individual variation in both males and females is significant.
c - More information on the size of Ussuri brown bears
A decade ago, on the former AVA Forum (now Tapatalk), an article written by N. Kucherenko (published in a Russian magazin in 2003) was discussed more than once. The reason was it has a table on the size of adult Ussuri brown bears. I'm referring to this well-known table:
*This image is copyright of its original author
The table is a bit suspect (it isn't likely that 10 adult males ranging between 260 and 321 kg produce an average of 264 kg), but the confusion could be a result of a typo (likely).
Both male (196 cm as opposed to 211 cm) and female (160 cm as opposed to 181 cm) bears seem to have been somewhat shorter (referring to total length) in Kucherenko's day, but that could have been a result of coincidence or the method used to measure them. The difference between measurements taken 'over curves' and measurements taken in a straight line is considerable in brown bears (see -d-). Another disadvantage of this method (referring to a measurement taken 'over curves') is it can be applied in different ways.
The main difference between both tables, however, is the difference in (average) weight. Kucherenko's females in particular were significantly heavier. The difference could have been a result of the aim of his paper (written to lure hunters to the Russian Far East), but it's also likely large individuals were more common back then. In the first decades after WWII, bears were not often hunted.
There's more information about exceptional female brown bears in a few threads of the former AVA Forum (now Tapatalk). A member from China (KTKC) posted what seemed to be reliable information on a few large females. Here's a scan of one of his posts. The female brown bear, from northeastern China, was 275 kg:
*This image is copyright of its original author
Some years ago, another document on Ussuri brown bears was published. Seryodkin was involved in that one as well. Here's a scan of table 1. Two of the three male brown bears were collared in the Sichote-Alin Nature Reserve. The young adult male (6-7 years of age) was 180 kg, whereas the adult male (8-10 years of age) was 235 kg:
*This image is copyright of its original author
d - Difference between curve and straight line measurements in brown bears
The two iriginal tables posted above (see -b-) say adult female Ussuri brown bears average 181,17 cm in length, whereas adult males average 211,63 cm: a difference of 30,46 cm (almost 1 foot). Assuming they, like most brown bears, were measured 'over curves', the question is how long they were in a straight line. This is necessary in order to be able to compare them to adult wild Amur tigers.
Unfortunately, there's no information about the length of Ussuri brown bears measured in a straight line. Assuming they more or less compare to brown bears in the Americas, the question is if there's a bit more about American bears. The answer is affirmative.
About a decade ago or so, I scanned and printed a table about the dimensions of American brown bears posted in a thread of AVA (now Tapatalk). As a result of problems with the PC, I lost a lot of information. This means I'm unable to tell you anything about the source of the table. The print, however, survived. Here it is:
*This image is copyright of its original author
The table has detailed information about the dimensions of male grizzly bears by age class measured in the period 1975-1985. My guess is the table is about brown bears captured in Yellowstone, but I could be mistaken.
Anyhow. We're interested in 'Length (A)' and 'Contour length (A1)'. Length (A) is the straight line length, whereas contour length (A1) is the total length measured 'over curves' ('contours'). In adult male grizzly bears, that is to say bears of 5 years and older (bottom of the table), the average difference between both methods is 32,2 cm (164,3 cm as opposed to 196,5 cm).
The question is if male grizzly bears can be considered as adult at age 5. My guess is most authorities consider a male brown bear as adult when he reaches 8-9 years of age. Males of 5-7 years of age would be considered as young adults. In order to be able to compare American male grizzly's with male Ussuri brown bears (see the table in -b-), I only used male grizzly's of 8 years and older in order to get to a comparison.
The conclusion is the average difference between straight line and curve measurements in adult male grizzly's (8 years and older) is 36,2 cm per age class (range 7,5 - 60,9). There are significant differences between age classes. In two 13-year old male grizzly's, the average difference between both methods was 14,0 cm and in two 16-year old male grizzly's the average difference was 7,5 cm only, whereas it was as much as 60,9 cm in five 11-year old males. Strange.
Anyhow. In 30 (the 15-year old bear was left out of the equasion as he was measured in a straight line only) adult male grizzly bears, the average difference between both methods was 36,2 cm (14,25 inches).
The American male grizzly's, by the way, averaged 95,7 cm (range 83,0 - 105,0) in height and 135,1 cm (range 116,0 - 150,0) in chest girth.
Do American male grizzly bears and Ussuri male brown bears, as was assumed (see above), really compare? Not quite. What I have suggests Ussuri male brown bears are a bit larger in all departments.
The two 8-year old males weighed in October were just over 200 kg and the 8-year old weighed in May was 220 kg. The other four male bears, all weighed in the period May-September, averaged 298 kg (range 256 - 363 kg) or 657 pounds. Big by any standard.
e - Difference between curve and straight line measurements in Amur tigers
In this post, the focus isn't on Amur tigers (Panthera tigris altaica), but Indian tigers (Panthera tigris tigris). One reason is there is much more information on the length (and weight) of tigers shot in what used to be British India. Another is there is good information about the methods used to measure tigers in that part of the world in both magazins and books.
Tiger hunting always was quite popular in British India. From 1860 onward, the number of hunters more or less exploded. A few decades and tens of thousands of dead tigers later, hunters concluded regulation was badly needed in order to prevent total destruction. This, mind you, was well before the turn of the century (referring to the period 1880-1900).
In this respect (the destruction of the natural world), British India and Russia (referring in particular to the regions, ehh, aquired from China in 1858 and 1860 (nowadays the Russian Far East) definitely compared.
If you want to know more about the situation in the Russian Far East, my advice is to read 'Taming tiger country: Colonization and environment of the Russian Far East, 1860-1940'. The dissertation of Mark Sokolsky (2016) is extensive and very interesting.
Here's a map showing the territory gained by Russia in 1858 and 1860:
*This image is copyright of its original author
The destruction of the natural world in the Russian Far East is also described in 'Dersu The Trapper'. In the first decade of the 20th century, Vladimir Klavdievich Arseniev and his guide Dersu thought the slaughter they saw would result in mass extinctions in a few decades only. They were right. In the twenties and thirties of the last century, Amur tigers (as well as many other species) really walked the edge. It was a close call.
Returning to British India, tigers and the methods used to measure them. As far as I know, only Forest Officers and a few experienced hunters measured tigers in a straight line in the period 1860-1890. Nearly all tigers shot in that period were measured 'over curves', that is. As this method, which can be applied in different ways, not seldom produced tigers of exceptional length, debates about the reliability of these records erupted quite often.
Sterndale ('Natural history of the mammalia of India and Ceylon', 1884, pp. 162-163) was the one who proposed to measure tigers in a different way. His proposal to measure tigers in a straight line ('between pegs') was adopted in most parts of Central India, but in northern India, Assam and southern India many hunters continued to measure tigers 'over curves'.
Here's a scan of pages 162-163 of his book:
*This image is copyright of its original author
The Maharajah of Cooch Behar ('Thirty-seven years of big game shooting in Cooch Behar, the Duars, and Assam. A rough diary', Bombay, 1908) and his guests measured all tigers they shot in the period 1870-1908 'over curves'. Just before and after the turn of the century (1898-1902), however, 12 male tigers were measured 'between pegs'. Of these, 10 were measured both 'over curves' and between pegs':
*This image is copyright of its original author
The table, which has one error (the tigers were shot in the period 1889-1902 and not in the period 1989-1902), was posted in this thread in January 2016. It shows the average difference between both methods in 10 male tigers shot in the period 1889-1902 was 5,45 inches or 13,84 cm (range 5-7 inches). These 10 tigers, largely as a result of one long tiger, averaged 290,17 cm in total length measured 'over curves' (range 274,32 - 317,50) and 276,35 cm 'between pegs' (range 261,62 - 300,99). The average head and body length of 9 males was 199,53 cm measured 'over curves' (range 186,69 - 210,82). Of these 10 males, 8 were weighed, of which one was 'gorged'. They averaged 455 pounds (range 385 - 504) or 206,39 kg.
Compared to the average of all male tigers shot in the period 1877-1908 (n=89) in that part of British India, they were a bit shorter (290,19 cm as opposed to 294,84 cm). They also lacked a little over 6 pounds (455 as opposed to 461,34). Not one of the 89 males measured and the 53 weighed, by the way, was exceptional.
Why is this table posted in a post about the length of wild male Amur tigers? The reason is it, to a degree, can be compared to a table with the dimensions of 13 wild male Amur tigers captured in the Sichote-Alin Biosphere Reserve in the period 1992-2004.
I'm referring to Table 7.3 in 'Tigers in the Sichote-Alin Zapovednik: Ecology and conservation' (Miquelle (DG), Smirnov (EN) and Goodrich (JM), 2005). This publication is in Russian only, but the table is in English as well:
*This image is copyright of its original author
The tigers captured in this reserve were measured in the same way as the tigers shot in Cooch Behar, the Duars and Assam in the period 1870-1908 ('over curves'). The conclusion is they, in total length, more or less compared to the 10 male tigers shot in northeastern India a century ago (294,00 cm as opposed to 290,19 cm).
If the method used in Russia in the period 1992-2004 was applied in the same way as in northeastern India in the period 1870-1908, it means we have to deduct 5,45 inches (13,84 cm) from the total length 'over curves' to get to the total length measured in a straight line ('between pegs'). The result (294,00 - 13,83 = 280,17 cm) suggests wild male tigers shot in northeastern India in the period 1870-1908 and wild male Amur tigers captured in the Sichote-Alin Biosphere Reserve in the period 1992-2004 more or less compared in total length 'between pegs'.
Male tigers shot in Central India in about the same period as the tigers shot in northeastern India (refering to 'Wild animals in Central India', A.A. Dunbar-Brander, 1923) were a tad longer (281,94 cm in total length measured 'between pegs'), but the sample from Central India was larger and it included a few very large individuals. Lengthwise, one could, therefore, conclude there's little to choose between male tigers shot in northeastern (n=10) and Central (n=42) India about a century ago and male tigers captured in the Sichote-Alin Reserve (n=13) in the period 1992-2004.
Wild male tigers shot in Central India averaged 420 pounds (190,51 kg), whereas those shot in northeastern India averaged 461 pounds (209,11 kg). In order to find out more about the weight of wild male Amur tigers captured a century later, we need more information.
Here's a table with more details about 10 wild Amur tigresses and 11 wild male Amur tigers. It's very likely these 11 males featured in the previous table as well, but I'm not sure. As a result of the problems mentioned above (referring to computer crashes that resulted in a significant loss of information), I'm also unable to tell you anything about the source of the table. I only remember it was posted in one of the threads of the former AVA Forum (now Tapatalk):
*This image is copyright of its original author
When reading the table, one has to remember it includes tigers of 3 years and over. A wild male tiger of that age is considered as adult (as it's able to reproduce), but the information I have on weights, lengths and, in particular, skulls shows there are significant differences between young adult male tigers (3-4 years of age) and mature males (5 years and over).
Of the 11 male tigers in the table, four ('Alexei', 'Misha', 'Andrew' and 'Jack-2') were either immature or in bad health. One of them (I think it was 'Andrew', but I'm not sure) was in such bad shape he had to be euthanized.
Tiger 'Victor', who also made the table, was found in a snare by wildlife students in February 2004. He was sedated and taken to a small enclosure in Terney to recover. A few days later, he was released back into the wild. Although not as large as others, 'Victor', a mature male estimated to be 8-10 years of age, was 288 cm in total length measured 'over curves'. At 385 pounds (174,64 kg), he was described as " ... unusually fat and healthy ... " ('Against all odds', John Goodrich, 2004).
Tiger 'Dima', known for his preference for brown bears, was captured 3 times. The first time, he was 205 kg. Some time later, after he had lost 3 canines, he was 170 kg on a full stomach (...). The third time he was captured, he was 204 kg. He entered the table at 193 kg (205 + 170 + 204 = 579 : 3 = 193).
So what is the average weight of a wild male Amur tiger these days? The answer we don't know.
Those who expressed their opinion ranged between 389 (Slaght et al., 2005) and 430 (Miquelle) pounds, but the 11 male Amur tigers in the table above averaged 169,45 kg (range 125-200) or 373 pounds. If we remove the young adults and the tiger that was euthanized, the average of the remaining 7 males is 184,45 kg (range 170-200) or 406 pounds. The measurements suggest tiger 'Volodya' could have been a young adult as well. Without him, the average is 186,83 kg (almost 411 pounds).
An average is a result of selection and sample size. As to the sample. It's smallish, but it's the only one available. We have no option but to use it, that is. As to selection: the question is if males affected by natural conditions should be included or not. In a region known for tough conditions like the Russian Far East, one, I think, has to include the effect of these conditions, as it's the only way to produce an informative, and reliable, table.
For those interested in a table that has healthy adult males only: my guess for now is healthy adult (5 years and older) males range between 160-254 kg (354-563 pounds). Both limits are not a result of guesswork only.
Tiger 'Dima' mentioned above was 205 kg (452 pounds) when he had all his canines. Some time later, when he had lost 3, he was 170 kg (375 pounds) only. That, mind you, was on a full stomach. Without the roedeer he had eaten, he would have been about 350 pounds, if not less. In spite of his problems (referring to the 3 canines he lost and to his weight when he was recaptured), he made a full recovery: the last time he was weighed, he was 204 kg. The average for the 3 captures was 193 kg (426 pounds). This means the range in weight of a healthy adult male Amur tiger can be quite significant.
The heaviest wild male Amur tiger accepted by biologists was the male shot by Baikov near the Korean border in 1911. That male was 254 kg (563 pounds). The heaviest captured in the period 1992-2021 was 'Luk'.
Although quite heavy (212 kg or 468 pounds) for his length, 'Luk' still had some growing to do when he was captured. The photographs published show a compact tiger, but 'Luk', a young adult, was (significantly) shorter than average. This is important, as there was a strong relation between total length and weight in adult wild male tigers shot in northern and northeastern India about a century ago: male tigers exceeding 440 pounds were significantly longer (and heavier) than male tigers below that mark (440 pounds). As there's no reason to assume it would be different today (or in other regions), it seems quite safe to assume 'Luk', all other factors equal, would have been longer and heavier in his prime.
Heel width also is a factor to consider. What is known, strongly suggests there could be a (strong) relation between heel width and weight in adult wild male tigers (same in captive male Amur tigers). In this department as well, tiger 'Luk', if I remember correctly, wasn't exceptional. In heel width, adult wild male Amur tigers range between 10,0-12,5 cm. Exceptional individuals can reach, and at times exceed, 13,0 cm. A heel width of 13,5 cm has been measured more than once and captive male Amur tigers (referring to previous posts in this thread) can reach 14,1 cm.
I can almost hear you say my proposal regarding the average is a bit confusing as both historic and modern records were used. Furthermore, there's no real average, only a range, and a very wide one (165-254 kg) at that.
I agree on all points made. I could have used weights of male Amur tigers captured in the period 1992-2021 only. Furthermore, the tigers captured in that period were measured in the same way and weighed with the same machine. Another problem solved. In spite of that, I decided against it. One reason is the sample is small. Another is the sample included young adults and problem tigers. When the sample is smallish, both factors would have a serious effect. I'm not saying it would result in misinformation, but it could result in an incorrect picture.
The problem described, unfortunately, isn't easy to solve. The reason is a lack of data. My guess is the situation isn't going to change any time soon. Biologists, for good reasons (referring to the article on the results of footsnares published on a Russian forum some years ago), seem more reluctant to capture adult male tigers with Aldrich footsnares. The only wild Amur tigers captured today are orphaned cubs, immature (or young adult) tigers causing problems and (old) tigers affected by disease. If we want to know more about the length and weight of healthy adults in their prime, we have no option but to use information published in the period 2000-2010.
And that's it? Well, apart from historic records, we could use observations of experienced rangers and biologists. The problem is it's very difficult to get to an accurate estimate. And an estimate it will be, no matter what. Measurements of heel width, most probably, are more informative. And then there's camera traps. It would be best to combine sightings, camera trap pictures and measurements (referring to heel width), but chances are it won't happen very often.
Every now and then, pictures of large individuals are published. The pictures below show wild male Amur tigers possibly exceeding tiger 'Luk' (the young adult male of 212 kg) in length and weight, but remember it's only an opinion.
Here's a recent picture (2021) of a thick-set male from Anyuisky National Park (Chabarowsky Krai). The female also isn't small:
*This image is copyright of its original author
Frontal view of a robust male seen on a road well west of all reserves (2019). This photograph was first posted by our former mod 'Wolverine':
*This image is copyright of its original author
This photograph shows a male hugging a smell tree. I don't think he was exceptional, but it was a muscular male tiger:
*This image is copyright of its original author
This photograph (camera trap as well) shows a male clearly surprised. The heel width of this 'monster' tiger (assessment of the man able to get to a comparison) was exceptional (13,5 cm):
*This image is copyright of its original author
One more (2019) to finish this overview of large male Amur tigers not weighed by biologists:
*This image is copyright of its original author
As to the weight of large males. We can only guess, but chances are one or two might be quite close to the heaviest male Amur tiger accepted by biologists today. This male, shot near the Korean border in 1911 by Baikov, was 254 kg (560 pounds) and 11.8 (355,12 cm) in total length (see the picture below).
A male Amur tiger with a total length of of 355,12 cm? I agree it's remarkable, especially when we know the longest captive males actually measured were about 10.6 in total length in a straight line.
My guess is the skin was measured after it was removed. The giant tiger shot near the Sungari river in 1943 was 11.6 'over curves' in total length (350,52 cm). When the skin was removed, it taped 375 cm (12.4). If we deduct 10 inches from the length of the skin of the tiger shot in 1911 as well, the outcome is 10.10. This could have been the total length measured 'over curves'. Measured in a straight line, the tiger, most probably, was 10.2-10.4. About as long as the longest captive Amur tigers:
*This image is copyright of its original author
Was this tiger longer and more robust than the males shown above? We'll never know, but my guess is the difference is limited. Any chance of capturing a tiger of this size one day? Not likely. As far as I know, at least 2 males were able to break the binding or, worse, get out of the footsnare when rangers and biologists approached. Two biologists were attacked, but the damage, most fortunately, was (relatively) limited. I'm not saying it's impossible to capture a male tiger exceeding 450 pounds with a footsnare (far from it), but you never know.
This regarding the size of wild male Amur tigers measured and weighed by biologists in the period 1992-2021.
And what about the size of wild Amur tigers shot in the period 1880-1945? The document published in 2005 and discussed above has a table with 'historic' records as well. Those who had the opportunity to go over them, to keep it short, concluded most records are unreliable.
A justified conclusion?
I think so. I agree something more than a newspaper report or a vague photograph is needed to accept a record of a tiger of exceptional size. It is, however, quite another thing to reject most hunting records as products of hearsay only. Dismissing them out of hand would be as unwise as accepting them without solid proof.
Wild Amur tigers today, most probably as a result of the population bottleneck in the first decades of the last century, do not show the same amount of individual variation seen in other subspecies. This is not true for captive Amur tigers. The remarkable size of some individuals suggests hunting records should be taken a bit more serious. A lack of reliable information doesn't mean large tigers were a result of imagination only.
The tiger below, for example, was very real. Jankowski informed V. Mazak about the tiger and sent him a unique photograph. Mazak wrote about the tiger in the third edition of his book published in 1983. Less than a decade later, Jankowski's book was published. The tiger was mentioned in his book as well.
In spite of all that, the tiger never made it to a table. I agree it's an effective way of eliminating a record, but it makes you wonder about those going over historic records. Did they miss him completely, or did they decide he, for some reason, didn't qualify? The remains of the large male bear he had killed and eaten, by the way, were erased as well. By those convinced adult male brown bears are out of the predatory reach of adult male Amur tigers of similar size. They did a great job, but reliable reports about brown bears killed by tigers keep coming in and the bears killed are not as small as most assumed.
The Sungari River tiger shot in 1943 wasn't weighed, but estimated at 300-350 kg. If we deduct the bear he had eaten, he could have been as heavy as exceptional captive male Amur tigers seen every now and then (250-300 kg, possibly a bit more).
Here's a scan of the photograph published in Mazak's book. Notice the size of the skull:
*This image is copyright of its original author
Apart from hunting records, there is information about the size of wild Amur tigers found dead in the period 1970-1994. I'm referring to Table 1 in 'Conflicts between man and tiger in the Russian Far East' (Nikolaev (IG) and Yudin (VG), 1993).
Of the 38 male tigers in that table, 26 were weighed. Of these, 21 were 3 years or older (range 3,5 - 13). They averaged 159,8 kg (range 93-192). The tiger of 93 kg (200 pounds), 6-7 years of age, had a bullet wound. It's very likely he died as a result of starvation. The tiger of 192 kg (424 pounds) died shortly after a fight with another male. He suffered from a pathology of the paw and was no match for his opponent.
As to the cause of death of these 38 males.
At least 24 of these 38 tigers had been shot. Most were killed directly, but some (like the 93 kg tiger) survived, only to perish later. One was trapped and another tiger was poisoned. One male was killed by a bear near Komissarovska in 1972 (no information available) and another was killed by a wild boar near Vasilkovka in 1984. In 1985, near Terney, a tiger of 178 kg was severely injured by a horse. He drowned in a river when the ice broke. At least 5 tigers suffered from leg or paw injuries. In 2 males, it was the result of a disease. The others most probably were injured in a fight. Although (brown) bears could have been involved, tigers can't be excluded. I've seen different serious fights between captive tigers and noticed paw and leg injuries are not uncommon. It could be wild tigers also deliberately target paws and legs in a fight.
As to the age wild Amur tigers can reach.
One seldom reads anything about old tigers in the Russian far East. Of the 38 male tigers found dead in the period 1970-1994 (referring to the table of Nikolaev and Yudin discussed in the previous paragraph), four were 10 years or older. Three of them were weighed. The 10-year old male was 192 kg, whereas the older males were 136 and 168 kg.
Wild Amur tigers exceeding 12 years of age seem to be few and far between. I know of a female of 15 and read a newspaper article about a wild male tiger estimated at 15 years of age in the Siberian Times of 16-01-2019 ('Tiger king Tikhon who sought human help wants to return to the wild after having dental treatment'). According to the reporter, tiger 'Tikhon' visited A Russian border post in January 2019. He said he needed to see a dentist. As he insisted, they decided to help him. The dentist did all he could, but it was clear 'Tikhon', who had lost most of his teeth, was unable to continue his career in the wild. Although starving, 'Tikhon' strongly disagreed with the decision. A few weeks later, however, he perished. At 140 kg only (in another newspaper article he was 142 kg), he was thin as a rail:
*This image is copyright of its original author
*This image is copyright of its original author
*This image is copyright of its original author
The conclusion, to finish this paragraph, is 11 adult wild male Amur tigers captured in the Sichote-Alin Biosphere Reserve in the period 1992-2004 averaged 294 cm in total length measured 'over curves' (about 280-281 cm 'between pegs) and 169-170 kg.
Without the young adults (n=3) and the tiger euthanized later (n=1), the remaining 7 males averaged 298-299 cm in total length measured 'over curves' (range 288-308) and 184-185 kg (range 170-200). These 7 males averaged 198 cm (range 190-208) in head and body length (also measured 'over curves'), 124-125 cm (range 113-130) in chest circumference and 81-82 cm (range 78-85) in head circumference.
In head and body length measured in a straight line, they averaged 183-184 cm (198 - 14). The 8 male Ussuri brown bears discussed above averaged about 175 cm in total length measured in a straight line. If the tail was included (likely), it means they averaged about 165 cm in head and body length measured in a straight line. Male Amur tigers, therefore, are about 15-20 cm longer in head and body.
The main difference between both species is in weight: adult (8 years and over) male brown bears captured about 2 decades ago averaged 257-258 kg (see the table above), whereas adult male Amur tigers (referring to the 7 males discussed above) captured in roughly the same period averaged about 184-185 kg, maybe a bit more (190-195 kg).
All in all, the conclusion is adult male Ussuri brown bears, although a bit shorter, have a weight advantage of about 70-75 kg at the level of averages. If we add the also have longer necks and (slightly) longer skulls, the conclusion is their body is very compact and robust.
f - Individual variation in wild Amur tigers
There is plenty of information about individual variation in wild male brown bears, but not quite enough on wild male Amur tigers. What is known, will be described in the continuation of the series on the size of wild Amur tigers and Ussuri brown bears.
It won't be the second post of the series, though. I first want to tell you a bit more about the size of captive Amur tigers in European and Chinese zoos and facilities. One reason is there's good information about the size of captive Amur tigers in European and Chinese zoos. Although captive Amur tigers usually are a bit larger than their wild relatives, they offer a bit more insight in the potential of Amur tigers. Another reason is I recently received reliable information about the size of adult Amur tigers in 2 Chinese facilities from our member 'Betty'.
ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
