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

[GuateGojira]

(12-25-2019, 02:50 AM)Greatearth Wrote: I wish users in wildfact speak about different tiger subspecies such as the Chinese tiger, Indochinese tiger, Malayan tiger, Sumatran tiger, and extinct tiger subspecies instead of keep talking about the same topic on the Siberian tiger: their size, why they became smaller in size today, their populations, interaction with brown bears, and other things about Siberian tigers. Anyway, I have some topic to discuss on the northern Bengal tigers. I am dubious about those tigers are really larger than central Bengal tigers. I think it is just northern Bengal tiger fanboys are spreading rumor on those tigers are ultimate tigers. I saw fanboys were saying single northern Bengal tiger in Terai and Assam can take down the largest known prehistoric felidae, short faced bear, and even asiatic elephant. However, only reliable source of those tigers (Terai and Assam) are the Smithsonian tiger project in Chitwan. And two largest tigers, Sauraha (M105) and M126 were around 227~272 kg (272 kg was something inside of stomach). Sauraha seems to be 261 kg with empty stomach when he measured the last time, but he was bottomed 227 kg when he measured in 1974-1975. Sauraha was 198 cm from heady to body, 310 cm including his tail from what I know. He was similar in size to other largest tigers in Kanha, Bandhavgarh, ...etc. Assam tigers seemed larger in pictures because of their belly. The same as people think Wagdoh is the largest because he has massive body. However, I don't believe Assam tigers are longer and taller. They just have bulky and fat body since they are living in good areas and huge prey (Kaziranga and other places in Assam are the only places in India that allowing rangers to shot poachers). Northern Bengal tigers seemed to be larger if we add old data, but those data can't be trusted 100% if we compared to measurement from modern days by scientists. And many of huge size tigers were probably gorged when they were hunted/measured. Their overall sizes on length and height are similar to the largest tigers in other parts of India. Even Bachelor of Powalgarh was 323 cm long. However, I don't know if it was over curve or between the pegs. The measured data of todays' Himalayan tigers in Bhutan is no larger than tigers in central India. Thus, northern Bengal tigers are obviously similar in size as tigers in Bandhavgarh, Tadoba, Kanha, ...etc.

I don't know about tigers in western India in Ranthambore and Sariska. They look slim and lighter, but I don't know about length and height.

Indochinese tigers and Malayan tigers seemed very interesting too. Even though many Indochina to Malay Peninsula are similar rainforest, but they seemed to have different body sizes and appearance. However, I don't really have any old/today data of these tigers.

Actually, I have posted many information about the other tiger subspecies, here is a summary of one of my last posts with some modifications, males only (for the moment):



The Caspian tigers are calculated to be as large as the Bengal ones, but the few skulls available suggest a smaller size. The only three weights from males shows an average figure of 197 kg (range: 170 - 240 kg). One skull is said to have measured 385 mm in total length (Heptner & Sludskii, 1992) but a follow investigation suggested that the other measurements presented shows a specimen much more smaller and that probably the skull was measured over the bone, saldly the skull is lost forever (Mazák, 2013).

The Indochinese tiger was about the same than the Caspian tiger, if not slightly longer based in the skulls available. The biggest skull from a Caspian tiger was of 369 mm while a new skull apparently from Malaysia (based in DNA) was  of 370 mm. In the weight department very few figures are available in litterature, with just three males: one of 173.3 kg (Pocock, 1939), other of 182 kg (Mazák, 2013) and a big one of 259 kg (Bazé, 1957). Modern records are available thanks to the scientists working in Thailand at this moment, and based in 4 males (with 5 captures) the average weight is of 182 kg (range: 164 - 209 kg), about the same body mass than modern Amur tigers. So using the modern records plus the old records we got an average figure of 193.5 kg (n=8, range: 164 - 259 kg). For details check this topic, specially topic 68 and 81: https://wildfact.com/forum/topic-indo-ch...ers?page=5


The South China tiger is the smallest of the mainland tigers, if we take them as a single subspecies, and only lives in captivity now. Slagth et al. (2005) present a a list of captive specimens and the males from this population had an average weight of 130.7 kg (n=13, no range). A list of wild specimens from hunting records that I collected shows an aveage of 152 kg (n=8, range: 108 - 190 kg). The biggest specimens seems to be from the northern area and the smallest ones from the southern, se there was a cline in the weight of this population. I don't have figures from the tigers that are in semi-wild status in South Africa, but I guess that they are heavier than those in China zoos and maybe close to those from the old wild records.

Finally, the only other subspecies/population from which we have body mass records is the Sumatran tiger, the smallest tiger in modern days. Using modern scientific records we have an average weight for males of 127 kg (n=4, range: 98-148 kg). That sample also includes a male of 75 kg, it says tha was adult and in good health, but certainly there is an error in that figure: The smallest captive adult male recorded by Slaght et al. (2005; in Barlow et al. (2009=) is of 91 kg and came from a sample of 21 speciments, and also Mazák (2013) which recorded weights of wild and capivte specimens reported that the smallest male was of 100 kg. So the figure of "75 kg" came probably when the animals was first captured and obviously not in a good shape; other posibility is that there was a typo but I don't hink so. Using old hunting records, the average weight for Sumatran male tigers is of 119.3 kg (n=6, range: 104 - 140 kg), and using all the records for this subspecies we got to 122.8 kg (n=10, range: 104 - 148 kg). There is a record of a male of 180 kg but if that is accurate it will be an exceptional male and should not be included in the list. Also @"peter" measured a skull from a male of 350 mm in greatest length, which suggest that in the past big males existed in the island. There is also other record from a captured male of 130 kg posted here by a member but as we don't have the main source of it, I did not included the records in the modern records.

About the Malayan tigers, we don't have reliable weights from the wild in the old records. I found only one records of a male of 120 kg, but other news reports shows males of up to 170 kg, which will be not out of question. The figures showed by a report on Malayan tiger conservation as just estimations and reach a maximum of 130 kg. Slagth et al, (2005; in Barlow et al. (2009)) present a list of weights of "Indochinese - Corbetti" tigers but in fact this weights are from Malayan tigers in captivity, the average weight for males is 120.6 kg (n=6, range: 109 - 132 kg), this is closer to the Sumatran tigers than to the mainland ones. Reliable measurements from old records give average lengths as large as the South China and Indochinese tigers (Locke, 1954), and the skulls reported are big, with an average greatest length of 339 mm - n=4 (J. H. Mazák, 2008) and now we have a new skull of 370 mm from this area (based in DNA). This suggest that in the past the Malayan tigers were as big as South China tigers (average greatest skull length of 334.7 mm (n=10, range: 318 - 348) and in some case even as big as the Indochinese tigers. I had not calculated yet the average weight of this population based in the skull size, but certainly if we use the average figures from modern captive specimens, we will get a very low average weight for the tigers species, a one that will not reflect the real weight of the species in time.

For Java and Bali tigers, the situation is worst. We only have two weights for Javanese tigers and none for the Bali tigers. For Javanese male tigers, we have one wild male of 141 kg and other from captivity of 110 kg (Slagth et al., 2005; Mazák, 2013). The average of these two specimens will be 125.5 kg, which is slighly more than those from Sumatra overall and this is accurate as the skulls from the male tigers in Java are bigger than those from the other two islands. However, the weight of 141 kg belongs to an animal with a skull length of 331 mm, which is just a little over the average reported of 321.3 mm in the study of Mazák and Groves (2006) that also included inmature specimens. Also, the biggest skull measured for this subspecies is of 349 mm (Mazák, 2013) and he even concluded that based in the skulls, this tiger population was probably as big as the tigers in South China! Using the condylobasal length of several specimens I calculated an average weight of 134.5 kg (n=10, range, 110 - 158 kg), which I guess will be probably closer to the real average in the wild. For Bali tigers we don't have any weight, Mazák (1981) estimated a weight between 90 - 100 kg, but I calculated an average weight of 112.8 kg (n=3, range: 107 - 123), but we must take in count that Mazák did not knew the large skull of 301.5 mm in greatest length reported by Buzás and Farkas (1996). Also, my estimations based in the condylobasal length are using only captive specimens, if we use wild and captive specimens together the average figures will be:
* Java male tigers: 141.8 kg - n=10 - range: 116 - 166 kg.
* Bali male tigers: 118.9 kg - n=3 - range: 113 - 130 kg.
This may be a little more reliable figures, by I dediced to use the captive ones as the result obtained with the male of 141 kg was closer to the original (I got 144 kg with that specimen with condylobasal length of 294 mm.). However is interesting to see that the largest Bali male tiger, which had a skull size of the about the same length than the large jaguar males from the Pantanal, got a similar calculated weight.

We can try to estimate an overall average weight for the males of the species Panthera tigris, but we will need to use captive specimens and isometric calculations from skulls to fill the holes. Taking the risk, this is what I got:
* Bengal tiger: 200 kg - n=166 - range: 97 - 272 kg.
* Amur tiger: 203 kg - n=33 - range: 155 - 254 kg.
* Caspian tiger: 197 kg - n=3 - range: 170 - 240 kg.
* Indochinese tiger: 193.5 kg - n=8 - range: 164 - 259 kg.
* South China tiger: 152 kg - n=8 - range: 108 - 190 kg.
* Malayan tiger: 120.6 kg - n=6 - range: 109 - 132  kg - captivity.
* Sumatran tiger: 123 kg - n=10 - range: 104 - 148 kg.
* Java tiger: 125.5  kg - n=2 - range: 110 - 141 kg - one wild, one captive.
* Bali tiger: 113 kg - n=3 - range: 107 - 123 kg - isometrically calcullated.
** Overall average: 158.6 kg - n=239 - range: 97 - 272 kg.

This figure is pratically the same reported by Yamaguchi et al. (2009) and Kitchener & Yamagichi (2010), which says that the average weight for the male tiger at "species level" is c.160 kg. Now, remember that this list have many assumtions, specifically in the Malayan and Bali tigers. I used only to two known males for the Java tigers in order to use only true weights, but if I use the figure of 134.5 kg that I obtained from 10 skulls the average for male tigers overall will be 159.6 kg, practically the same figure with no diference. Now, if we use strictly only weights and only wild specimens, which will exclude the Malayan tigers (as they are captive), the Java tigers (as only one is wild) and the Bali tigers (as are calculated) from the sample, the average weight for male tigers as a species will be 178.1 kg (n=228, range: 97 - 272 kg).



About the Bengal tigers, I am of the idea that there is little variation amoung the populations in the subcontinent, with some top figures in the north region, here is the summary of all my sample from tigers in the Indian subcontinent at 12/2019:
                                             

Madya Pradesh, Central India:   201 kg - n=61 - range: 160 - 255 kg.

Karnataka, Southwest India       196 kg - n=12 - range: 159 - 227 kg.

Hyderabad, Southeast India      182 kg - n=  9 - range: 150 - 203 kg.

Rajasthan, Northwest India       243 kg - n= 3 - range:  220 - 268 kg.

Northeast India                         207 kg - n= 51 - range: 150 - 256 kg.

Terai, North India                       200 kg - n=17 - range:  161 - 259 kg.

Chitwan, Nepal                           224 kg - n= 7 - range: 180 - 272 kg.

The Sundarbans                        123 kg - n=6 - range: 97 - 172 kg.

As we can, there is some diference between populations. Body measurements also do not show a great variation, all of them been about the 190 cm in head body on average, but take care with body measurements, because a long tiger can be more slender than a short tiger, that is why the Sauraha male M-105 that had only 197 cm in head-body was larger than the male Darra T-03 from Nagarahole with 204 cm in head-body, as the Nepalese male weighed 261 kg empty and the Indian male weighed 227 kg empty.

About the Bachelor of Powalgar, the measurement of 323 cm was "over the curves", Mazák (1981) estimate it at about 310 cm "between pegs". However the total length alone is a bad estimator of size, as we must know the size of the tail. For example, the biggest tiger ever is not the longest, Brander (1927) measured this giant cat in Kanha with a head-body of 221 cm, but its total length was less than 305 cm because the tail was very short. Judging by the picture, the Bachelor of Powalgarh was also a giant and probably matched the large tiger of Brander.

About the tigers in Ranthambore, as far I know there are only 3 adult males captured, but check what Dr Jhala says:

*This image is copyright of its original author

Sadly, he did not provided measurements or weights. Now, these are the only figures that I have from the tigers in that region, confirmed by the authors of the articles:

*This image is copyright of its original author

I hope this can cover all your questions, for the moment. Reply