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

[peter]

RETURN 80

Yet another shipment of very interesting information. Many thanks! I'll discuss your last 2 posts in detail in a few days, because I need to go over de information I collected over the years first. I'm, in particular, referring to information I found in a number of journals. One of them, of course, is the Journal of the Bombay Natural History Society (JBNHS). In the early part of the 20th century in particular, many interesting letters of experienced hunters were published and discussed.     

As a result of your posts, the table in my last post (I'm referring to the table with information about 14 tigers posted by KTKC in the former AVA forum) has become more clear. All skulls mentioned in that table belonged to wild tigers and I also think all of them were from China. It's a pity we won't be able to solve the age problem completely, but my guess is most questions will be answered sooner or later. 

I agree there's some doubt regarding the gender of some tigers in the table. Tigers -05- (09414) and -09- (20460) might have been (adult) females. I'm not too sure about skull -10- (09417) as well. Could have been a youngish male or a very large female. Skull -02- (08193) most probably belonged to an adult male. 

As to skull -05- (09414). The former owner of skull had a total length of 283,9 cm 'between pegs' with a HB length of 185,5 cm (tail 98,4 cm). A tigress with a total length of almost 9.4 (referring to feet and inches), of course, is unusual, but I have a number of records of tigresses from what used to be British India that more or less compare. I'm not only referring to letters of hunters in the JBNHS, but to information from Forest Officers (referring to a number of books I read and discussed in this thread some years ago). Most tigresses (well) exceeding 9 feet (274,32 cm) were measured 'over curves', but most isn't all and Forest Officers, as a general rule, measured all tigers they shot 'between pegs'. Some tigresses shot in central and northern India exceeded 9 feet 'between pegs' in total length. Same for Nepal, although they were measured 'over curves'. The tigress shot in the Russian Far East in the 1929-1930 winter (referring to the Morden-Graves expedition) also was 9.3 measured 'between pegs', but she, like the two males that were shot, had a very long tail. Apart from that, there's recent information (referring to a number of articles I read). I'll post a number of scans in future posts.

As to the tigress shot in the 1929-1930 winter in the Russian Far East also mentioned in V. Mazak's book 'Der Tiger' (1983). The information you posted answered every question I had in that the skull measurements clearly show she was a young adult. The next question, of course, is if a young adult wild Amur tigress could be able to get to 167 kg and 9.3 in total length measured in a straight line. The answer, I think, is in one of the recent (Chinese) studies discussed in this thread not too long ago. The study had numerous tables of captive Amur tigers that showed captive Amur tigers quickly grow until age 3-4 (not much difference between males and females). During the transition to adulthood, however, they (no exceptions) lost quite a bit of weight. After reaching adulthood (5 years in females and 6 in males), they started growing again. In wild Amur tigers, it doesn't seem to be different. A seasoned Russian biologist who measured and weighed quite a number of wild Amur tigers recently said the largest male he had seen was a young adult. He added adult wild males averaged 220-240 kg, with some individuals reaching, and even exceeding, 280 kg). The interview (posted in this thread) was posted by our member 'Apex Titan'. 

The conclusions of this biologist contradict those of others. Batalov and Fomenko, both more than once, said a wild male Amur tiger exceeding 200 kg is considered as 'large' in most districts. My guess is we'll never know, because only few wild Amur tigers are weighed these days. There are, however, reliable reports about heavier tigers from northeastern China. Feng Limin, in a recent interview, said one male was 270 kg, whereas another was 250 kg. It is, however, not known of the 270 kg male was actually weighed. The weight of the famous 'Sauraha tiger' (from Royal Chitwan, Nepal), for example, was the outcome of a regression analysis. His exact weight wasn't know, because he bottomed a 500-pound scale with ease.     

I went over the dataset of Hartstone Rose numerous times, but, regarding the tiger skulls, was unable to find information as to the subspecies. Is there an appendix that has additional information about the skulls in the table? 

While I agree in general terms with the conclusion of many researchers (and posters) there's no difference between Indian and Amur tigers (referring to total length, weight and skull measurements), it has to be remembered the number of skulls of Indian tigers in (a limited number of) natural history museums (in the UK in particular) far exceeds the number of skulls of wild Amur tigers. Indian tigers, if anything, seem to have the edge, but most (large) skulls were collected in the period 1870-1950, when the number of wild tigers far exceeded the number of wild tigers today. Not a few hunters, after the appeal of Pocock (in the JBNHS), sent their 'best' skulls to the British Museum. Four of the skulls in the British Museum (referring to the dataset of 'Phenotypic plasticity determines differences between the skulls from mainland Asia', 2022) exceed the skull you mentioned in greatest total length. They were acquired in 1879, 1882, 1901 and 1950. I'm not suggesting I thought I saw a bit of selection at the gate, but it's clear the British Museum has a unique collection og magnificent skulls. In the Amur tiger skull department, the opposite seems to be true. Most skulls, even those in well-known Russian museums, were acquired in the period 1970-2010. This is the period Amur tigers seemed to be on their way out. When a big cat is heading in that direction, chances are it will affect the average size (also referring to information collected in northern India and Nepal about a century ago). The overview I saw (referring to the study mentioned above) suggests skulls of young adults may have been included. Last but not least is large Amur skulls tend to disappear these days. In one of his last posts, our former member 'Wave Riders' said the (large) skulls V. Mazak measured in the sixties and early seventies of the last century (in Berlin) were gone.   

Based on the information I have, I'd say Himalayan and Kaziranga tigers top the list of averages (referring to total length and weight), but in the department of outlyers, Amur tigers stand a very decent chance. I've seen too many exceptional individuals (referring to Amur tigers) to conclude they're few and far between. I would, for now, however, agree with those who think the difference (in size) between captive and wild Amur tigers is remarkable. Could be a result of the population bottleneck in previous century, but it could also be a result of a lack of data. Unclear. Reply