Modern weights and measurements on wild tigers

[GuateGojira]

(01-23-2022, 04:43 AM)Khan85 Wrote: Here you can find very detailed measurements on 38 bengal tigers (11 males + 19 females) along with age - growth curve chart, collared in Panna and some other National Parks. 




https://www.pannatigerreserve.in/BOOKLET%20ON%20TIGER%20BODY%20GROWTH%20.pdf

Remarks about the biggest male 
I think that P-111  is the biggest male tiger in the study. 

- Captured 5 times in total 


Capture 3

- Age = 5yr 6 mn
- Weight = 226.7 kg
- Head Body length = 184 cm 
- Total length = 283 cm
- Shoulder height = 127 cm
- Neck girth = 70 cm
- Chest girth = 154 cm


Capture 4 

- Age = 8yr 10 mn
- Weight = N/A
- Head Body length = 211 cm
- Total length = 311 cm
- Shoulder height = 120 cm
- Neck girth = 76 cm
- Chest girth = 154 cm


Measurements were taken in straight line, I believe (first, the length of head and then the length of body). In capture 3, his head-body length was 184 cm and total length was 283 cm at the age of 5yr 6mn. On his 4th capture, his head-body length increased to 211 cm and total length increased to 311 cm. 

Since the strongest correlation of weight is with HBL/TL, he could have been heavier than 226.7 kg on his 4th capture.

I was checking the information on the tables and also checking the comments from other posters about it. So, this is my first impresion on the data:

1 - The information is good, but it has errors, however that is not necesarily a dissaster, I have saw other studies when the data is even more problematic, like that of Hobatere lions for example. Like many other modern documents on great cats, like for the example the Indian lions reported by Dr Jhala or the Kalahari lions from Dr MacFarlane, the tables do had errors but this is probably because they manage to much information and one incorrect movement in your keyboard may create an important damage.

2 - There are a few incongruences in the data, that is why in the next table, were I summarize the information of the adult specimens over 3 years old, I decided to include also the measurements and weights of some specimens when they were cubs or young adults in order to see if there is an increase or what effect is presented. Check this:

*This image is copyright of its original author

In the table you can see that, with the males at least, the problem is with male P-111. What I noted is that some information make sense IF we order it in a different form. For example, that chest girth of 132 cm definitelly is not from a cub of less than 2 years, but it correspond with a male over 5 years old. The body length of 211 cm definitelly is not the one from  when he has less than 3 years, that is for a older male. So what I see here, and what I suspect, is that they put the incorrect information in the incorrect ages. Interestingly the tail length did make sense, so I guess that the data may be correct but is mixed. Finally the very small chect girth of 75 and the abdomen girth of 90 cm do not appear in pages 25 - 28 where is the summarization of the information, so again, I guess that this is human error and that information came from a cub or small young adult female.

Other thing that I see is with female T-4, check that the body measuremenst when she was over 8 years old are very small, in fact, it looks like a cub, so again, I think that is another error. With female P-213 we can see all her changes since more than 1 year up to 9 years, It looks like she was decreasing in size since the 3 years old, which do not make sense and the chest girth of 136 cm with the belly girth of 104 cm as definitelly of a male, or if we put it at other way around, the chest of 104 cm is an adult female not a cub, and the belly of 136 is a big male or a heavelly gorged female, which is not the case for a cub of only 87 kg.

Finally the female P-213 (22), at less than 2 years, are reported with measurements from an adult female and a very large one (chest of 124 cm is more for a male). So again, is this an error of mixed information? That is my only explanation.

So, the data is useful, I think that we can use it if we ignore the information that seems incorrect, but at the end the main issue that the measurements in red do not match the age reported or in some cases, the sex of the animal. If someone can contact one of the authors and get an explanation that will be great. Reply