ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)

[peter]

B - ANSWERS

a - Bias

In your lead-in, you announced you would try to get to a series of 'unbiased' remarks, but I took the liberty of adding a few pounds of salt and hope you don't mind. The reason is nearly everyone is preferenced to a degree. It's clear I'm more interested in tigers than in other big cats or bears and your first two posts, in my opinion, show a clear preference for bears and lions.

I don't mind, as our forum has quite many posters interested in tigers. We could do with posters with a different approach for some more balance. Consider yourself most welcome.      

b - Length

This is the table on American male grizzly bears again. They averaged 196,5 cm. 'over contours' and 164,3 cm. in 'length'. I assumed 'length' is the total length 'between pegs'. You didn't agree as the tail apparently was included. I agree on the tail, as there's no information on tails in the table.

*This image is copyright of its original author

This is the table on male brown bears in north-eastern Siberia again:

*This image is copyright of its original author

 
Body length, in this table, really is the length of head and body, as the length of the tail is given seperately. The length of head and body, as is usual in brown bears, most probably was measured 'over contours'. If not, the Siberians were giant weasels, so 'over contours' it is.

How does their head and body length compare to male Amur tigers? We know male Amur tigers (animals of 36 months of age and over) taped 195 cm. 'between pegs'. As the male Siberian brown bears averaged 196,5 cm. 'over contours' and 164,3 cm. in 'length' (let's assume it was a straight line length), I assumed they more or less compared to their American relatives (160-165 cm. in a straight line).

You didn't think the 'length' was measured in a straight line, but that it was " ... a curved distance probably not matching any contour ... ". An intriguing proposition, but you have to admit 'contour length' is right next to 'length', meaning it had to be something very different. My guess is it compares very much to a 'between pegs' measurement in big cats. 

As your last remark (" ... brown bears in the RFE are reliable reported at much larger body size then that of any tiger ... ") contradicts your remarks on 'length' (you concluded I overestimated the length of male brown bears), I propose to forget about it.

The conclusion I got to is both American and Siberian male brown bears (at the level of averages) are shorter in head and body length measured in a straight line than male Amur tigers. 

One last remark on a measurement 'between pegs' in big cats. A big cat is measured in this way by measuring the distance between the tip of the nose and the tip of the last bone of the tail (hairs not included). The length of a big cat measured in a straight line, therefore, is the length 'as the crow flies' (the tape shouldn't touch the tiger). In brown bears, 'length' (not 'contour length') is measured in nearly the same way. Problem solved.  

c - Skull

This is a well-known table on the skull of Ursus arctos piscator (left) and Ursus arctos beringianus (right). It seems that 'beringianus' includes Ursus arctos lasiotus. A bit confusing, as coastal brown bears, like those on Kodiak Island and, possibly, Sachalin, often have a clear 'stop' (elevated brow), whereas this feature is not seen in skulls of Ussuri brown bears ('lasiotus'). Anyway:

*This image is copyright of its original author

        
How to read the table? Warsaw told me that -1- is greatest total skull length, whereas -2- is the condylobasal length. The table (of Baryshnikov, if I remember correctly) says 19 males of Ursus arctos beringianus (Ursus arctos lasiotus) averaged 377,03 mm. in condylobasal length and 407,84 mm. in greatest total skull length. Impressive by any standard.

Now for male Amur tigers. I assume you are familiar with the table published by V. Mazak (1983, pp. 191)? Male tigers averaged 325,44 mm. in condylobasal length (n=9) and 367,10 mm. in greatest total length (n=8). A difference of 15,85% in condylobasal length and 11,10% in greatest total length (in big cats, the sagittal crest often is relatively long, hence the difference).

I agree it is a significant difference, although not as pronounced as you announced. The main reason why brown bears have a longer skull, is a very long snout. Furthermore, we have to remember that Amur tigers have a (relatively) wider rostrum, longer and stronger (referring to the diameter at the insertion of the upper jaw) canines and more force at the tip of the canines. In a fight, a long snout and a deficit at the tip of the canines would be a distinct disadvantage. Undecided, I would conclude. 

d -  Weight

You wrote over 40 wild male Amur tigers averaged about 180 kg. (range 146-225), whereas male brown bears (according to Kucerenko) averaged 264 kg. (range 260-320). You then proceeded to the giant bears shot every now and then in the past. I propose to go to the essentials. Tigers first.

In the Kerley-table published a few years ago, male Amur tigers averaged just over 170 kg. The table, however, included young adults and malnourished animals of 125 kg. and just over. What about a table which has healthy adults only, with 48 months and older for adults? We distinguish between age-classes in bears, so why not in tigers?

Miquelle said adult males average 430 pounds (195 kg.). In Guate's table, the average was just over 420 pounds (190 kg.). The data I have suggest the average ranges between 420-430 pounds for a healthy adult male. The heaviest I know of was 212 kg. There could have been one of 473 pounds (214,5 kg.) weighed by Kerley, but I never saw a reliable report about the 225 kg. male you mentioned. Half a century ago, the situation was quite different in that adult male Amur tigers often exceeded the heaviest weighed today.      

Now for brown bears. We all know the Kucerenko-table (minimum 260 kg. - average 264 kg. and maximum 320 kg.) was suspect in that the minimum had to be incorrect. Same for his table on female brown bears. The average for females (189 kg.) was corrected by poster Alexious3. He said 140-150 kg., would be closer to the mark. Later, he was proved right: females average about 145 kg. My guess is the average for males could be quite a bit below the mark suggested in different tables (264 or 270 kg.).

If we assume the average difference between males and females, as in Kucerenko, is 70-80 kg., the average for males could be 210-230 kg. My guess is it probably is a bit more, but I doubt if we would get to 264 or 270 kg. if young adults, malnourished 'problem' bears and old bears would be included. I propose to include the exceptions to the general rule in every table on male brown bears from now on. I mean, if you include male tigers of 3 years of age as well as malnourished animals and jump to conclusions from there, we should include young adult male bears, old ones and problem bears struggling to survive as well. I also think we should include the violent weight fluctuations resulting from fattening up and hibernation. The difference between autumn and spring weights can be quite astonishing in brown bears. If we do all that, a very different picture emerges.

There are more reasons to doubt the average weight of male brown bears and one of these, like in Amur tigers, is a lack of data. There's not that much known, meaning chances are Kucerenko's table, in spite of the flaws mentioned, will remain important. My guess is it will change when the situation, datawise, changes. 

I recently found a bit more on the weight of male brown bears in Sichote-Alin. It was, in fact, straight from the lion's den, ehhh, the bear's den (the Shaggy God forum). Sarus recently posted an abstract of a study conducted in Sichote-Alin. A study on brown bears (Ursus arctos lasiotus) in Sichote-Alin. Three adult males monitored in the fall (when bears are heavier than in other parts of the year) were well below the assumed average for adult males belonging to Ursus arctos lasiotus (referring to the Kucerenko-table):

*This image is copyright of its original author

*This image is copyright of its original author

 

Seryodkin was involved in the article recently written (Sarus posted a link to it). As Seryodkin was involved, Warsaw, who was a little bit disappointed, had to accept the records. 

To conclude. There's overwhelming evidence that Ursus arctos lasiotus is a large local type with a lot of impressive averages, though, in total length and chest circumference, not more impressive than those of male brown bears in northeast Siberia. Compared to them, however, they are decidedly heavier. Or are they? 

Bears show more individual variation than tigers, meaning there are both small and large animals. The differences between small and large also are more pronounced. And then there is hibernation, meaning weight fluctuations of 20-30% and even over. A male of 235 kg. in autumn could be 170-180 kg. in early spring. Very close to the Tatibe River bear killed by the tigress mentioned in Bromlej (1965). An average-sized male of 270 kg. in autumn could be close to 200-210 kg. in spring.

Just suppose a male bear of this weight meets a male tiger with an excellent memory in his prime somewhere in April, when the tiger is well over 200 kg. A tiger like him:

*This image is copyright of its original author

Or him:

*This image is copyright of its original author

Or T-16:

*This image is copyright of its original author

I'm not saying smallish or average-sized male brown bears are killed by large male Amur tigers in remote places at an alarming rate. I'm saying the information I have on brown bear weights doesn't quite add up. It could be 270 kg. and it could be, as in females, quite a bit less. When it is, as I think, well below 270 kg. and male tigers, as Miquelle said, average 195 kg., it would be easier to explain the lack of interaction between adult males. It would also be easier to explain the lack of evidence regarding displacement.     

e - Body structure

At 160-165 cm. in a straight line without the tail and 1,25-1,50 kg. or even a bit over per cm. in length, adult male brown bears belonging to Ursus arctos lasiotus are taller, chestier and significantly heavier than adult male Amur tigers. They also have a significantly longer skull, which, in the posterior part in particular, is reinforced as well. I do not doubt adult male bears are suited for conflict, especially when it happens on two legs. The reason, apart from being plantigrade, is short distances between the different body parts and bulky departments with a lot of room for bones, organs, muscles and improvement over time. This is without stamina, of course. The ultimate candidate for victory in a bout with a big cat of similar weight? 

Male Amur tigers, at 195 cm. in head and body in a straight line and about 1 kg. per cm. in length (referring to males of 36 months and older), seem to be very close to male brown bears according to those who know. For weapon quality, most agree, they could compare. Amur tigers have the biggest fore-arms and paws of all big cats and they also are taller than most male brown bears. This advantage would enable them to strike downward and manouvre the bear in a position in which they are able to use their teeth first. Although bear skulls are made to withstand damage, tiger skulls are a platform for significantly longer upper canines.

Close in most respect, I think. The difference then has to be in the distances and, perhaps, in the stamina. We can dismiss stamina, as there are plenty of reliable records of tigers involved in long bouts. They need breaks when they fight large animals, but they apparently are able to continue for a long time. That leaves short distances and plantigrade. Here's what I know about serious fights (based on what I saw myself and heard of those who saw a lot more):

Although tigers do not lack in the plantigrade department, bears are naturals in this respect. There also is no question about absolute and relative strength in that bears top the list. That, however, doesn't mean tigers lack in these departments. They are strong enough to manouvre an opponent of similar size and weight in a position to strike first. It is about initiative and strike first and this is why agility, speed and aggression are very important. If one of the two is able to get to an essential part of the body with his teeth, the fight usually is quickly over, plantigrade or not. The real fight is when both are down and wrestling. Agility as I see it is the ability to get out of a dangerous position as fast as possible and get to a decisive advantage seconds later. It is about using the teeth and forcing your way in. Robustness, I think, isn't relevant when both are down and teeth come into play. The reason is it doesn't produce speed, but, at best, damage control. Important, but not when vital body parts are mauled or when your life is at stake.  

The fights between adult wild male tigers we saw in videos recently posted underline what I saw myself and heard from trainers. In a serious fight, the opponents often go down quickly and wrestle their way towards the best possible position to use the teeth. When they find a place to use them, they lock on for as long as they can. Bears are different in this respect in that they often are referred to a biters. Only experienced male bears know they have to hold on when they fight a big cat. The best chance of a bear is to strike when the tiger is taking a break. In this way, they use their advantage (robustness) in the best possible way. 

Although many favour the big cat in an all-out in similar-sized animals (referring to weight), it's nearly always very tight. There are no clear favorites. When we hear or read about bouts and decisions, the winner, in nearly all cases, had a significant advantage (size, age, gender and experience). One seldom hears about a winner in a fight between similar-sized animals. The reason is they know it can be deadly.   

Whether or not body structure is an advantage in a fight between animals of similar size and age, depends on the way the fight is conducted. You wrote real large male brown bears, apart from other large bears, have no enemies. I agree. But that doesn't mean this is a result of robustness or something related. It is a direct result of size and not something else, like robustness and short distances.

When a 400-500 pound male bear fights a male tiger of similar weight, anything is possible. When the difference is over 30% or so, chances are there will be no prolonged fight. In wild Russia, contrary to what many think, male brown bears do not dominate male tigers in a fysical fight. Says Krechmar, and they don't come more experienced. He also said a large bear would get it his way more often than not. Of course he would: size is important and a tiger can hunt again. But it definitely is the exception to the rule. Krechmar's remarks, by the way, suggests there isn't much to choose in the weight department. 

One last remark on body structure and fights. Let's assume male Amur tigers average 420-430 pounds and male brown bears average 580-600 pounds. How do you explain the lack of interaction and no casualties in engagements? A result of tigers avoiding bears? If so, then why is it researchers, in over two decades, didn't find anything on male tigers consistently displaced by male brown bears? I mean, bears and food. Do I need to say more? My guess is it is too close to call, maybe as a result of smaller than assumed differences in weight and maybe as a result of other factors. Male tigers know and so do male brown bears.

f - The Tatibe River bear killed by a tigress

We agree in most respects, so there's no need for a debate. The point I tried to make, however, was that a tiger (or tigress in this case) apparently is able to kill a heavier bear. You thought it would make sense if the bear was young and therefore unexperienced. I agree and so would most others. But what if the bear really was well over 200 kg. before hibernation? And what to say if it was a small adult male or a large adult female?

As Bromlej didn't offer any details and we want to stay clear of speculation, I propose to go to trainers. Brown bears are as strong as they come, they think. But they also saw bears, and males in particular, overplaying their hand at times. At their peril, they added. I talked to one of the most experienced and respected trainers (the adopted son of one of the Hagenbecks, who had been a trainer nearly all his life and later became director of a training facility). He had seen it all and said anything is possible in a fight. It usually goes with weight, age and gender, but he knew of plenty of exceptions. At times, a leopard can kill a larger big cat and a big cat can kill a larger bear. Bears also kill big cats, but most, if not all, of these were decidedly smaller. When I asked for details, he said polar bears had been killed by tigers in a one-on-one. Not immatures, he added. Happened more than once. I also read about it in Tiede's book.

In the end, it depends. This is the opinion of most trainers and it is the opinion of many researchers in Russia. The only thing they seem to agree on is male Amur tigers do not hunt male Ussuri brown bears. My guess is they do not avoid each other, but I do think they avoid problems when they, at times, engage. Those that didn't (tigers and bears), were youngish, old, desperate or handicapped in some way. Very large male brown bears no doubt top the list, but it's a close call in the other weight divisions. 

g - To finish

I talked about short and clear posts in my previous post, only to break the record moments later. I apologize. The reason is I wanted to asnwer all points made in a single post in order not to lose the overview. I succeeded, I think, but I can't deny it has become a very lengthy affair. Won't do it again.

To make up for it, a photograph of captive polar bears to finish with. Warsaw always complained about the size of brown bears and polar bears in circuses. The old trainer I interviewed didn't agree with 'small'. Polar bears were his speciality. He said they were more wild at heart than brown bears and more dangerous than big cats, but also more preferenced. If they liked you, you could do nothing wrong. Males would defend you against other males. The bond he experienced was tighter than in all other animals.    

He told me about a book I should read. After his death, I found and bought it. It has many photographs of large polar bears in circuses. In the photograph below, the female trainer was a bit short. In spite of that, it shows polar bears in circuses were anything but small. Males of 500 kg. and well over were not rare, he said. I agree: 

*This image is copyright of its original author

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