Modern weights and measurements on wild tigers

[peter]

SIZE OF INDIAN TIGERS 

A century ago

A century ago, the region just south of the Himalayas produced the longest tigers (total length measured 'over curves'). Chitwan tigers topped the list. Assam tigers shot in the same period, although shorter, were heavier than those shot in northern India, but the Maharajah of Cooch Behar weighed nearly all of his tigers, whereas Sir John Hewett didn't. 

The tigers he wasn't able to weigh were significantly longer than those he weighed. Back then, there was a strong relation between total length and weight in Indian tigers in that long tigers were relatively heavier than shorter tigers. The difference was about 6-7 pounds per inch.   

If he had been able to weigh all tigers he shot, Hewett's average for northern India would have well exceeded that of Assam. Although the average for Assam males was 461 pounds, 450-455 would have been closer to the mark. The reason was a number of 'gorged' tigers. Based on what I had, I got to 475-490 for northern India and a bit more for Nepal.

Today

Many years later, 7 males captured in Chitwan averaged 520 pounds. Although the average was adjusted later, I decided for 520 in order to be able to compare tigers shot a century ago with those captured in the seventies and eighties of the last century.

The comparison I did says there's not much to choose between back then and today for (total) length, but tigers weighed in the last decades were heavier than a century ago. Based on what I have, I'd say that the difference is 20-40 pounds at the level of averages, maybe even a bit more in regions with large tigers.

To be more concrete. The averages today (males of 6 years and older), depending on region (not including the Naga Hills and the Sunderbans) and the local conditions, could range between 420-520 pounds. As exceptional individuals can exceed the 'normal' maximum by 25-35%, males well exceeding 600 pounds can be expected in northern India and Nepal every now and then. The heaviest shot in unmolested Nepal (705 pounds) was 10.9 'over curves' in total length. My guess is that tigers of that size are still around. The problem is the scales used by biologists. That and a lack of experience in darting exceptional individuals.   

Exceptional individuals  

Tigers in northeastern India might top the table for skulls. A century ago, skulls of large males ranged between 360-400 mm. (greatest total length). Not one of these even approached 10 feet in total length measured 'between pegs', meaning they were not of exceptional size. The photographs and videos I saw suggest they (males and females) still have more rounded and larger skulls than elsewhere. Different breed, so it seems.

Exceptional individuals are most often seen in large ecosystems. The larger the system, the better the chance to see an exceptional tiger. Seen in this light, the region just south of the Himalayas (from Rajaji to Kazirangha) and southwestern India (Western Ghats) still top the list. Central India has a chance when reserves are connected. Tigers need a lot of space. 

Based on what I know, I'd say that northern India is the region to visit if you're interested in large tigers. The Rajaji tiger is the largest I saw, but the reserves just east of Rajaji (up to and including Dudhwa) also have large tigers. Same for Chitwan, of course. Tigers in northeastern India often appear to be more massive, but they could be shorter and not as tall. The big skull can result in a somewhat distorted view as well.  

Arunachal Pradesh

I'm very interested in the situation close to the China border (Arunachal Pradesh). Authorities said that two captive, but wild-caught, tigers (male and female) were quite different from your typical Indian tiger: different coat (less stripes), more aggressive and larger all the way.  

I read quite a few books written by people in the know who spent their days in northeastern India. Not a few of them said that male tigers in that part of India were following elephants. They often found remains of youngsters killed and eaten by tigers. Could that culture have resulted in specialisation?

There are reliable reports about lions hunting elephants in some regions of southern Africa and tigers hunting rhinos (including adult females) in northeastern India. Time to read a bit more about the fauna in that part of India, I think. Which large mammals are seen in elevated regions in northeastern India? Reply