Who is the "king" of tigers? - Bengal or Amur

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Nepal tiger’s food intake and adjusting of its weights
 
I think is fair to get to a conclusion here: Contrary to Waveriders previous assumptions, we now know that the Nepalese tigers did not gorge themselves, probably thanks to a high prey base and absence of competition for the kill. There are about three or four cases of tigers eating large quantities of food (35 kg males: McDougal, 1977; 30 kg females: Sunquist, 1981), but from 38 studied kills and baits, it was established that tigers (male and female) eat between 14-19 kg in a period of 24 hours.
 
In Kanha, Schaller (1967) found that tigers normally eat between 18-27 kg in a day. This often quoted figure had the problem that is based in 7 observations, and includes only one male, in one single event. For the females, Schaller observed a female with cubs that eat 22 pounds (10 kg) per day, based on “several kills”, however he discarded this figure from its range, together with other observations of tigresses eating 15 and 11.3 kg, probably because in these cases the tigresses were with cubs. The other problem is that there is no form to know if the intake of 27 kg for that particular male (in that particular moment) was “the norm” or if it was “an exceptional” event. These points must be taken in count before starting to make comparisons.
 
These are the only two studies about food intake made in the wild by scientists, and as we know, only that of Chitwan is based in a large sample.
 
Now, for the baited tigers, Sunquist (1981) clearly mentions that the captured tigers have been always disturbed from the kills, which means that they have not eat to its full at the moment of the capture, something confirmed by him via email. In this form, he suggested that we could subtract 14 kg (the average for 24 hours) from the stomach content in order to adjust the animal’s weight. However, new evidence arises: the tigers were probably less than 12 hours in a bait!
 
In the book “Tiger Moon” from Fiona Sunquist and her husband Mel Sunquist (1988), she describe that all the tiger captures were made in the morning, beginning in some cases at the 3:00 am, as it was a little hard to found the tigers and they most found them before middle day. The baits, on the other hand, were settled about the 6:00 pm. These leave us a period between 5:00 – 6:00 pm to the 8:00 – 9:00 am of the other day to the tiger to eat, which is about 14 to 16 hours. However, we must take in count that the bait was never killed exactly just after the people settled the baits, but much after that, probably as much as 10:00 pm – 12:00 am, which is when tigers were roaming them territories. Apart from that, tigers never eat the kill in the same spot where they make the hunt, but always drag them some distance and lick the prey in order to take out the fur and open the carcass. With all this in mind, we can calculate a window of less than 12 hours for a tiger to eat calmly.
 
If we take in count that the figure of 14 kg was the proposed figure in 24 hours, we can guess that the figure for 12 hours most be less, probably about 7 kg, or maybe 10 kg for a large male. In this case, I think that is more than safe to use the figure of 10-14 kg to adjust the weight of the tigers and tigresses in Chitwan (at least for the average figures), while the figures of 30 – 35 kg are just random events and should not be used to adjust baited animals. This completely disqualify the assumption of Yamaguchi (in Kitchener & Yamaguchi, 2010) that the largest tiger capture in Nepal weighed as low as c.218 kg, together with the fact that no tiger has been recorded eating over 40 kg, not via reliable sources at least (Baikov described that Amur tigers eat up to 40 kg, but there is no evidence that he actually recorded one of those events).
 
Now that we know that Nepalese tigers ate about 14 kg in 24 hours and that they stay less than 12 hours at a bait, we can safely state average figures of 221 kg for males and 130 kg for females in the region, taking in count that the real figure could be somewhat more.
 
Now, on the heaviest specimens, Waveriders stated that the heaviest tigress (T-101) recorded her highest figure of 164 kg when she was pregnant and thus, this figure is unreliable. However, I don’t remember any document stating this (Sunquist monograph, Tiger Moon or other papers from Seidensticker and others). I think that Waveriders was referring to her first capture in 18 Dec of 1973, when she was without any cub and she weighed 150 kg (Seidensticker et al., 1974), then she was probably pregnant. Some years latter, this same tigress was captured again (3 Mar 1975) and this time she weighed 164 kg and in the same month (21 Mar 1975) it was also captured her cub T-103 (The Roaring tigress) which weighed 52 kg. A third capture of T-101 (11 May 1976) produced a weight of 153 kg (Sunquist, 1981). So, it is clear that the figure of 164 kg was not produced when T-101 was pregnant as she was with small cubs at that time, so the previous statement saying that the weight was unreliable, is inaccurate and should be discarded. Adjusting her with the previous food intake figure of 14 kg, T-101 could weigh c.150 (c.331 lb) empty.
 
On the side of the males, it has been discussed (and proved) ad nauseum that the figure of 261 kg is not the real weight of the Sauraha male (T-105), but a calculation (or “estimation”, if you prefer this word) based on a chest girth-weight equation and that the “real” weights were the figures produced by the bottomed scales of 500 lb and 600 lb used through the several captures of this specimen. At the end, the conclusion was that this male tiger weighed over 272 kg, and subtracting the 14 – 19 kg from its probably last meal, and including at least 5 – 10 kg of the bottomed scale, the final weight was c.260 kg (c.573 lb) empty, which seems reliable and accurate, matching with the calculated figure of Dr Dave Smith. Now, if we discard the “bottomed” values of 5 – 10 kg that I suggested, the weight of the Sauraha male is still of c.256 kg (c.564 lb), which is not so different from the original accepted figures. This is probably the same case with the male M-126 and the other two males reported by TigerLuver.
 
Now, some people (and posters) will like the idea of Yamaguchi that ALL Nepalese tigers were “gorged” and full of beef, which will produce a figure of 237 kg for T-105 (minus 35 kg; still not as low as the ridiculous figure of 218 kg that he stated) and 134 kg for T-101 (minus 30 kg), however the evidence of the scientists that ACTUALLY were in Nepal show that this is impossible, as no tiger was gorged in they captures, they simply don’t have the time to eat that much, this is something that Yamaguchi ignores.
 
Finally, for the smaller specimens:
* T-102 (the Dakre male) was baited (confirmed) in both captures (Seidensticker et al., 1974; Sunquist & Sunquist, 1988), so we most correct its weight. Using the intake of 14 – 19 kg, it will produce an “empty” weight of c.184 kg. I used both daily figures because as it was a male, I don’t want any people saying that males eat more.
 
* T-116 was baited but she was in a bad state, with fractured carpal and metacarpal bones in one forelimb and a gangrenous area in one hip (she died in that capture). She weighed 116 kg, adjusted with the 14 kg the empty weight was c. 102 kg, very low but accurate taking in count her bad health.
 
The case can be closed now. [img]images/smilies/wink.gif[/img]
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