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

[GuateGojira]

The average figures are always a changing factor, based on sample size and the inclusion of old, gorged or young animals, like you have explained very well. For example, The average figures of Brander, Hewett and Cooch Behar (without gorged specimens) range between 190 to 205 kg ( about 419 - 450 lb). However, the factors mentioned above affected the results, although we most take in count that these three figures represent the largest samples available and no other records reach its size. Those in southern east India are very light, probably own by the fact that this area is relative dry (Hyderabad), in comparison with other habitats.

For modern figures, they are subject to interpretation. For Nepal, there are now about 10 males (7 from Smith et al. (1983), 2 more from personal communications with Tigerluver and finally the male M126), and the average "empty belly" should be of no less than 230 kg this time. The advantage here is that scientists DO separated adults from subadults, there are no old or decrepit specimens and the stomachs are already adjusted for stomach content. On the Nagarahole-Panna side, the samples are too small to reach a conclusion, so the results are only suggestive. In the case of Nagarahole and the entire Western Ghats, is interesting to see that the other few males hunted in the area are of the same weight-size than those captured by Dr Karanth, suggesting that in fact, Southern tigers are lighter in body weight than for example, those from northern India and Nepal.

Finally, a quick review on the records, show that although the average figures seems larger in modern times, in comparison with the old ones, I guess that if similar sampling method would be used, the average of all mainland tigers will range between 210 to 220 kg, which seems realistic for such a large and variable population (excluding the Sundarbans, of course). For the maximum figures, it seems that between 255-260 kg seems to be the normal figures and anything over that could be classified as exceptional. On the lower figures, old records mark a figure of 159 kg, reported by Sanderson, Brander give one of 160 kg and Hewett with the Maharaha of Cooch Behar give similar results (161 kg and 168 kg respectively) However, it is unclear if those males were actually "adults" or just young males between 2 to 3 years old, which are already independent and have an adult sized body.

In Nepal, Dr Sunquist captured a young tiger that already measured 289 cm in straight line, but that only weighed 159 kg. For an untrained eye, the animal was already an adult and it was sharing the habitat with another male proving that tigers are not territorial. However that is a common interpretation of people that don't know the social relations of the animals (Shankala is a good example). The TRUTH is that this was still a cub of about 18 months old and the other male (T-105) was his father, and he shared some time with him. On the size issue, I can bet that Brander-Hewett-Maharaja of Cooch Behar will believe that this was an adult male, light but large, what a huge mistake for them!

In modern samples for Nepal, other young tigers have weighed up to 450 lb (204 kg), while the lightest male captured by scientists is the dominant male Dakre (T-102) which weighed 200 kg (about 184 kg adjusted for stomach content). This suggest that the smaller adult male in India and Nepal should weight no less than 180 kg, which incredibly match with the lower range proposed by Mazák (1981). Karanth (2003) propose a figure of 175 kg, but this is based in the records of Pocock (1929 - 1939) and the only similar weight reported in the books of this Zoologist is one of a male from Indochina, not from India (Karanth state a range of 175-260 kg for males in south east Asia, not India "alone", eye with this).

Other young males in list are the Ranthambore tiger of 220 kg which was between 3 to 4 years old and the less than 3 years old male from Panna which already weighed 180 kg. This suggest that those "adult" tigers of between 160 to 170 kg were:
a. Young adults of less than 3 years.
b. Malnourished males.
c. Injured males (like the male of 365 lb hunted by Hewett).

Based in the evidence and from my own, particular, point of view, I think that old and modern adult male Bengal tigers of >3 years old, weigh between 180 to 260 kg and average about 210 to 220 kg, depending of the region. Take in count that this figures are not graved in stone, and variations could occur, this are just suggestive figures that could change with more samples.
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