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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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 (06-08-2015, 06:42 PM)'brotherbear' Wrote: I would be interested to see a comparison of an Ussuri brown bear and an Amur tiger to scale in such a manner at some point in time.That is 100% possible, as we already have the Amur tiger image and size, and the size of the bear came directly from Kucherenco. The only thing I need is a photograph from a good side view of an Amur bear. However, If we don't found one, I could use a random brown bear and make more obscure its skin in order to resemble the Amur bears (just a little trick [img]images/smilies/tongue.gif[/img]). 
The bear actually appears smaller than the tiger, even though he isn't, because of his compact build. According to the measurements, the bear is slightly longer, but here again, not really so. The bear has a longer neck and a longer muzzle than the tiger. Also, the shoulder hump adds to the bear's shouder height. All-in-all, I would consider these two at roughly size parity. Of course, after many on-line conflicts, I realize that there are many interpretations of size parity. Still in all, I consider these two predators living within the same general location as among the most interesting animal relatuionships in the natural world. And yet so little is known.
 (06-10-2015, 12:02 AM)'brotherbear' Wrote: The bear actually appears smaller than the tiger, even though he isn't, because of his compact build. According to the measurements, the bear is slightly longer, but here again, not really so. The bear has a longer neck and a longer muzzle than the tiger. Also, the shoulder hump adds to the bear's shouder height. All-in-all, I would consider these two at roughly size parity. Of course, after many on-line conflicts, I realize that there are many interpretations of size parity. Still in all, I consider these two predators living within the same general location as among the most interesting animal relatuionships in the natural world. And yet so little is known. What Im really curious about is Wolf numbers where Tigers and Bears co exist? I would assume that they would not be as successful in areas where they would have to compete with both of these animals at the same time.  brotherbear\ dateline='\'1433876570' Wrote: The bear actually appears smaller than the tiger, even though he isn't, because of his compact build. According to the measurements, the bear is slightly longer, but here again, not really so. The bear has a longer neck and a longer muzzle than the tiger. Also, the shoulder hump adds to the bear's shouder height. All-in-all, I would consider these two at roughly size parity. Of course, after many on-line conflicts, I realize that there are many interpretations of size parity. Still in all, I consider these two predators living within the same general location as among the most interesting animal relatuionships in the natural world. And yet so little is known. Male Amur tigers average 195 cm. in head and body length in a straight line. Male Ussuri brown bears average 196 cm. 'over contours'. Same as Yellowstone male brown bears. As the Yellowstone male brown bears were 32 cm. shorter in a straight line (164 cm.), one has to assume the Ussuri's would be about similar if they would have been measured in a straight line. Male Amur tigers, therefore, are 31 cm. longer in head and body length in a straight line. Seen from this perspective, one could say Guate was quite generous to the Ussuri male brown bear in the comparison. Guate was generous in other respects as well. Kucherenko wrote Ussuri male brown bears average 264 kg. (583 pounds) and Goodrich said they average about 270 kg. (596 pounds), but 2 adult males recently weighed in the Russian Far East were 180 and 235 kg., or 207,50 kg. (458 pounds) on average. Quite a difference, that is. Same for females. Kucherenko wrote they averaged 189 kg. (418 pounds), but recent information points towards 140-150 kg. (320 pounds). As I don't know what to make of it, I propose to take 543 pounds (246,30 kg.) for now and assume it's a year-round average. In females, the average would be 369 pounds, say 360-380 pounds for now. The average for male Amur tigers, on the other hand, could be a bit higher in most departments. The WCS-table used by Guate included a number of young adults (a). Some of the tigers, weightwise, were well under par (b). Three is the Aldrich footsnare used to capture Amur tigers failed on at least two occasions ©. This means large males might be able to break free, which would affect the average to a degree. Not saying those who escaped the footsnare were well over 440 pounds, but they were large males and they were not weighed. All in all, one could perhaps say healthy male Amur tigers, at 190-200 cm. in head and body length measured in a straight line, average 420-440 pounds, whereas male Ussuri bears, at 160-170 cm. in head and body length measured in a straight line, could average 490-520 pounds. Male Ussuri brown bears, therefore, are both absolutely and relatively more robust. They also produce more exceptional specimens. When both animals would be seen close to each other, the picture that emerges could be close to the one Guate produced. Here's the table on Yellowstone brown bears I referred to above. It is about the average difference between 'length' and 'contour length' in 55 adult males (older than 5 years of age) at the bottom of the table. Also take notice of the average chest girth, height and neck girth:  *This image is copyright of its original author Here's a photograph of a male brown bear of 275 kg. (607 pounds) who reached 223 cm. on his hind legs. It was posted a long time ago by Warsaw. The bear, if I remember correctly, was exhibited somewhere in Canada, but I'm not sure:  *This image is copyright of its original author This is the famous picture of the diorama again. The more I see it, the better I like it. Based on what we know, it could be quite accurate. Both are about similar in length (tiger a bit longer), but the bear is more robust and heavier:  *This image is copyright of its original author The scenario in the photograph (male against male) is an unlikely one. Bart Schleyer, based on what he saw in the snow, said that tigers who hunt bears (most often older males) usually have about a 100 pounds on them. This advantage allows for a quick kill (a bite to the base of the neck). In at least two cases, the ambush developed into a 20-minute fight. The most likely reason was size in that both bears involved, adult females, were (visually) estimated at 150-200 kg. The male tigers who fought them probably were about similar in weight. In both cases the brown bear was killed, but the tigers were injured. Some Ussuri male bears follow tigers in order to rob or even hunt them. These 'satellite bears' target immatures and females with cubs. In Heptner and Sludskij (German translation of 1980), a number of incidents between large male brown bears and tigresses or adolescent tigers were described. The conclusion is male brown bears, like male tigers, prefer to attack smaller animals. There's no question males clash at times, especially in years with crop failure and mass migration of prey animals (deer and wild boars), but all-out fights seem to be singular events.
While studying a similar chart on yellowstone male grizzlies, I once averaged the weights of bears 9 years old and up and the average came to roughly 500 pounds. I agree with my old friend Big Bonns that there is really no such animal as the average grizzly, but 500 pounds seems to be very likely about right for Russia and the Yellowstone grizzlies. Thanks for the info.
(06-10-2015, 12:13 AM)'Pckts' Wrote:(06-10-2015, 12:02 AM)'brotherbear' Wrote: The bear actually appears smaller than the tiger, even though he isn't, because of his compact build. According to the measurements, the bear is slightly longer, but here again, not really so. The bear has a longer neck and a longer muzzle than the tiger. Also, the shoulder hump adds to the bear's shouder height. All-in-all, I would consider these two at roughly size parity. Of course, after many on-line conflicts, I realize that there are many interpretations of size parity. Still in all, I consider these two predators living within the same general location as among the most interesting animal relatuionships in the natural world. And yet so little is known.What Im really curious about is Wolf numbers where Tigers and Bears co exist? In 'Rote Wolfe und Weisse Tiger' (Bonn, 1952), German writer, naturalist and hunter Joseph Velter visited an Udege village with his local companion Pau (an Udege). Velter wrote he went to 'school' for some time. At the Udege school, he learned about tracking, the climate, the wind, habits of local animals and the skill of hunting. One of the local specialties was the wolf trap. It was a clever construction made of wood. Took some time to build it, but it was effective. Once a wolf entered the trap, he couldn't get out. Pau, encouraged by Velter, built the trap in a few days and caught 23 wolves in 6 weeks only. A lot of wolves in a region also known for tigers. Just before the trap was built, two Amur tigers were seen only a day away. The hunter who had seen them said he had seen tracks of other tigers as well. This suggests tigers and wolves lived in close proximity in the eastern part of Sichote-Alin a century ago. In those days, hunters distinguished between two types of wolf. One was the grey timber wolf and the other was a local subspecies with a reddish colour. According to Velter, they didn't mix. Both lived in large family groups. Red wolves in particular were not afraid of humans. Velter was treed by them when he shot one by accident. One often reads tigers and wolves can't co-exist in eastern Russia. One reason is tigers hunt wolves. Although Velter's observation contradicts this idea, Sysoev, in his story 'Amba', wrote the tiger who featured in his story ambushed, killed and ate a wolf. From the details and the lengthy description, I concluded he might have witnessed the hunt himself. If not, he could have talked to someone who did. There is more. This year, a wolf was killed and largely consumed by tigress Ilona. It wasn't the first time a wolf was killed by an Amur tiger (see 'Large Carnivores and the Conservation of Biodiversity', Island Press, 2005, Chapter 10), but 5 incidents in almost half a century suggests it has to be regarded as something out of the ordinary. What to make of it? Sichote-Alin still has wolves. They are seen every now and then, usually alone or in small groups. The large packs Velter saw a century ago seem to have disappeared. Is it because of the tiger? If so, why? I know tigers hunt wolves occasionally, but this wouldn't explain why wolves live in small groups in Sichote-Alin. If anything, one would expect the opposite. But Sysoev wrote the wolf killed by the tiger lived in a pack. A pack, therefore, doesn't seem to offer protection. Maybe wolves are considered a pest in Russia. It's one of the few countries where they occasionally hunt humans. More important, they severely affect the number of ungulates in some regions. Not appreciated in a country where hunting is considered more important than most other things. Maybe wolves suffer from a lack of prey animals in Sichote-Alin? Maybe it takes too much energy to hunt in packs in a region where energy conservation is important? Anyhow. This is a photograph of the wolf killed by tigress Ilona:  *This image is copyright of its original author
Excellent topic, i really enjoyed reading this thread since a year :)
To add something on the tiger - wolf interaction in the russian far east, i found a study regarding to this: https://books.google.at/books?id=ndb0QOv...&q&f=false A book called "Large Carnivores and the Conservation of Biodiversity" with a chapter called "Tigers and Wolves in the Russian Far East: Competitive Exclusion, Functional Redundancy and Conservation Implications" I found this accidently on wikipedia, as reference for interaction between tigers and other carnivores. Sometimes i read wiki articles, to see if they adapted the newest level of research. I was quite surprised... Some table scans from the book:  *This image is copyright of its original author  *This image is copyright of its original author In summary, from what I've understood after reading this, tigers limited wolf numbers due to competition about similiar prey and direct interspecific conflict. At the end of page 188 it's written: Accounts of historical shifts in the abundance of tigers and wolves are especially well documented in the Zapovedniks, where long term monitoring has been conducted. For instance, in Lazovski Zapodnik, Bromley (1935) reported that, although wolves were formerly absent, 105 wolves "had to be destroyed" in the 1940's, coincident with the low density of tigers. Wolf numbers declined consitently from the 1960's to the 1980's, at the same time as tiger population were recovering in the reserve. Wolf tracks rarely observed in the 1990's, and no tracks were registered in 1992 and 1993, where tiger numbers were high and stable (Khramtsov 1995). In a time confronted with habitat loss and limited prey items, it sounds convincing, that wolves suffer a similiar effect from tigers like african wild dog's do from lions (officialy). Is it possible, that in old days (like the times of Velter) the coexistence between tigers and wolves was perhaps a result of better environmental conditions? It sounds logical, but i don't know the conditions from those days... Apart from that, are there any documented interactions between Bengal tigers and tibetan wolves from the past? Sadly, in places where both share the same habitat, either wolves or tigers became very rare, like Nampdapha or Manas on the Bhutan part. (06-10-2015, 01:41 PM)'Brehmji' Wrote: Excellent topic, i really enjoyed reading this thread since a year :) The Indian Wolf is extremely rare, the only interaction between the two that I know of is a single wolf harassing B1 and B1 pays little mind to it for obvious reasons. Dhole and Tiger interaction is another story, there are few stories of many dholes dying while fighting with a lone tiger but this brings up questions as to why? Why loose significant pack #'s to kill a tiger? Its fishy at best, but its proven that tigers hunt dhole and @peter recently posted a awesome video of a tigress chasing a dhole pack all over, giving more credence to the idea that dholes are simply prey or pest to Tigers and nothing more. Dholes have become extremely rare in India, they are almost non existant in areas where tiger #'s are growing, is this due to tigers or hunting and deforestation or all 3, we don't know yet. But I assume its the same as Lion v Wild Dog #s Dholes or wild dogs are simply to small and even with large pack #s they can't compete with the much larger cat. Barring a pack of 50 individuals who are completley commited to fighting a full grown tiger or lion, I just don't see any chance for them to compete without more land and prey to support all. But a grey Wolf is completely different story, a pack of grey wolves may not be a serious threat to a male tiger or bear but they certainly will be threat to youngsters or cubs and possibly a tigress and they could possibly run off adults of either species from a kill if the pack is large enough. Grey wolves are large animals and work great together, 10+ of them is a threat to any animal IMO.
I watched a Nat Geo documentary several years ago of a big male grizzly in Yellowstone who skipped his winter sleep and spent the entire winter following a large pack of wolves. He was even filmed walking within the pack. Each time the wolves made a kill, the bear would enjoy the "lion's share." A big male grizzly can displace a pack of wolves from a kill regardless of the number of wolves.
(06-11-2015, 05:17 AM)'brotherbear' Wrote: I watched a Nat Geo documentary several years ago of a big male grizzly in Yellowstone who skipped his winter sleep and spent the entire winter following a large pack of wolves. He was even filmed walking within the pack. Each time the wolves made a kill, the bear would enjoy the "lion's share." A big male grizzly can displace a pack of wolves from a kill regardless of the number of wolves. I saw it. It also was observed in Russia, but most brown bears who skipped hibernation, as far as I know, didn't survive. Could be a result of the long winter and could be a result of a lack of servants, I mean wolves. I know some of these 'satellite bears' follow and extort tigresses with cubs, but this strategy apparently doesn't pay in the long run. A brown bear who skips hibernation in eastern Russia very often starves to death:  *This image is copyright of its original author 
@peter, I've a very important question regarding skull measurements in literature. Christiansen, using a digital method of measurement, began playing with positioning of the skull for measurement. The result seems to be his skull measurement method does not match with the conventional one in older literature. As the picture shows:
 *This image is copyright of its original author Method A is the method you have used as well as other literature from the last century I've read. Method B is Christiansen's new method. Method B looks to measure a short length. Now, have you read/met anyone who has used the method B skull position for length measurements? To all, examine the photos, have I made a mistake in measuring the length lines in the lower picture?
Hi Brehmji,
Thanks for the link. I took my time reading Chapter 10 (Miquelle et al.) in 'Large Carnivores and the Conservation of Biodiversity' (edited by Ray J.C., Redford R.H., Steneck R.I., and Berger J. - Island Press, 2005). Very interesting. I made some notes and will return to tigers and wolves in a few days. Liked your posts. Welcome to the forum, Peter. 
tigerluver, if I could just put my two cents in to your question, I was under the impression that the correct way to measure carnivore skulls is without the mandible, so method B seems to be the correct one?
The resting position of the cranium on the mandible is very similar to the resting position of the cranium, as the canines normally protrude a bit further from the cranium than the condyles. Although, von Koenigswald measured his skull resting at this angle. Yes, vK measurements are odd throughout, but Dr. Marciszak also looks to have measured this way as the measurement is show with a bird's eyeview of the cranium. In person, I suppose it's much easier to set the cranium naturally and then take the measurements.
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