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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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Sumatran tigers kill one and trap five
This newspaper report also is well-known. I decided to post the link anyhow, because the story is quite remarkable. It happened in Aceh (Atjeh) in the extreme north of Sumatra: http://thejakartaglobe.beritasatu.com/ne...onal-park/  (04-19-2015, 08:23 AM)'peter' Wrote:Interesting, but still, I found too weird that a Sumatran tigress, without been obese, could reach such a weight (152 kg).(04-19-2015, 08:14 AM)'GuateGojira' Wrote: I think there is a mistake in the document. With 152 kg, that was a Bengal-Amur (or hybrid) tigress or is a male Sumatran tiger. By the way, peer-reviewed document are not always perfect, even with revisions, I have read many documents that are latter corrected by they authors, despite the review of the publishers.
I know, Guate. It is strange that the 3 adult Sumatran tigresses in Dreamworld, all very healthy, are about 70 kg., whereas other tigresses of the same subspecies, also very healthy, seem to reach the weight of a large adult male Sumatran tiger. Of course one has to be wary with records, no matter what.
On the other hand. The amount of individual variation in Sumatran tigers is more outspoken than in other subspecies. Sumatran tigers are the only ones where males and females, skullsizewise, overlap. Some of the skulls of adult wild Sumatran tigresses I measured were shorter than an average Bali female, whereas others were only marginally shorter than an average male Sumatran male tiger. Some of the male skulls I measured, on the other hand, were hardly longer than an average female skull. This is why I concluded Sumatra could have (had) two distinct types (both sexes). I'm probably wrong, but this is what the skulls told me. 
Interesting observation on the Sumatran skulls, Peter. I know you're sample size is quite large, so the trend is probably significant. In my head, rather than having two forms, there's probably some type of positive allometry (body sizes grows much faster than skull size) going on in the relation of skull size to body size in Sumatran tigers, accounting for why skulls differences between genders aren't great but size differences are, at least based on the accepted data, still significantly different. Either that, or the Sumatran form was/is losing sexual dimorphism, but I doubt this theory based on the size data available.
I remember an article about tiger skulls in which J.H. Mazak concluded that sexual dimorphy in Sumatran tigers, skullsizewise, was more outspoken than in other tiger subspecies (...).
It's remarkable that a well-known pro and an amateur both interested in tiger skulls got to such different conclusions regarding Sumatran tiger skulls. I would definitely be interested in a debate in order to find out a bit more, but chances are this will only happen when my book will be published. Could take some more years, I'm afraid.
Just a little of theory for the discussion:
Mazák (1981) estimated that a female Sumatran tigress weight between 75 - 110 kg, but it seems that he doesn't discriminated about wild and captive animals, also he doesn't published the source of his data on body size and weights. Barlow (2009; from Slaght et al. (2005)) stated that captive Sumatran tigresses average 86.7 kg (n=21; range: 61.9 - 107.3 kg). It seems that the estimation of Mazák of c.110 kg (if its an estimation) seems somewhat correct, at least for captive specimens. I think that maybe wild Sumatran tigresses could reach a little more, just like male Sumatran tigers do: Mazák (1981) stated a maximum of 140 for male ones, but the heaviest wild tiger from the island, captured by scientists, weighed 148.2 kg (Slamet). Taking all these data, I can't believe a figure of 152 kg for a female one, despite its posible large size and skull dimensions. I propose to email the author(s) of the document, let's see what they say. Remember the case of the "250 kg" Suamtran tiger in an official document, that at the end, it resulted in a mistake and the figure was probably in "pounds". Edit: I think that I have found the problem. A quick research in some books and in the Internet and I have found that the weight of 9.7 kg for a seval fits more in the range of females rater than males. Probably that is the mistake, that the tiger was a male and the serval was a female. Yes, this could be just a wild idea, but I am going to write to Dr Diogo to clarify the issue.  (04-29-2015, 09:09 AM)'peter' Wrote: DHOLES AND BIG CATS The middle video is awesome, tfs. That tigress was definitely trying to get those dholes and that is by far the best and longest interaction I have ever seen between the two. (04-19-2015, 10:23 AM)'GuateGojira' Wrote: Just a little of theory for the discussion:Did you remember the case of the 152 kg Sumatran tigress? Whell, I send an email to Dr Diogo today and he answer me right now. Here is the answer:  *This image is copyright of its original author Well, it seems that, in fact, it was a FEMALE!!! More incredible, there is a record of a Bengal tigress of 189 kg from Madrid, Spain. We have now two records of exceptional captive tigresses, confirmed by scientists. [img]images/smilies/biggrin.gif[/img] Good day. Edit: At petition of @sanjay, I covered the email of Dr Diogo. Greetings. 
@GuateGojira , Excellent work. However I suggest that when you publish screenshot of such mails, Also hide the email of scientist or person who has replied. This is because publicly available email is used by spammers to send irrelevant emails and flood their inbox with spamming. We must also respect our scientist privacy.
I can understand you have shown it because you want to make sure the information is from valid source and its real. So you can either hide half part of email or provide them in PM to those who ask for it. Hope you understand.
Yes, I understand, but in this case I think that it was irrelevant, as the email was already in public, check this:
 *This image is copyright of its original author As you can see, the email is already available. Now, if you want the correction, I will do it that right now. [img]images/smilies/wink.gif[/img]
Then, not a problem. I thought it is his personnel email. In the case of public email there is no such problem
I have covered the email of Dr Diogo, at your petition.
What is interesting is that he answered in less than an hour, and that is close to a miracle, as scientists normally answer after one or two days, or maybe they don't answer at all. Thanks Dr Diogo!!! [img]images/smilies/smile.gif[/img] I will try, again, to ask Dr Chundawat about Madla tiger measurements, let's see if after all this time, he finally answer me to this.[img]images/smilies/huh.gif[/img] (05-02-2015, 01:54 AM)'GuateGojira' Wrote:(04-19-2015, 10:23 AM)'GuateGojira' Wrote: Just a little of theory for the discussion:Did you remember the case of the 152 kg Sumatran tigress? Whell, I send an email to Dr Diogo today and he answer me right now. Excellent work, Guate. It seems those involved did their job well. Captivity no doubt had an effect on the weight of the Sumatran tigress, but the report underlines the conclusion I got to when I measured skulls: Sumatran tigers are the only ones where males and females overlap in size. The amount of individual variation also is significant. I also think the accepted limits regarding maximum and minimum size are incorrect. When I was in Madrid some years ago, I visited the natural history museum and the zoo. The zoo didn't have tigers at that time, but I heard about the large tigress. What we know on size is a result of many individual observations. Although I do not doubt the averages often quoted are close to the actual averages, I also do not doubt the amount of individual variation is, or rather was, significant. I've seen documentaries shot in India in which large females (over 150 kg.) featured more than once. Just recently, I bought a book written by D. Witter. One of the females he shot was 9 feet in length and estimated at 450 pounds. A bit over the top, one would think. But the picture shows a large animal. Two others were 8.5 and 8.7. In another book, a male just below 9 feet is mentioned. Although short, it was the most robust and heavy tiger the writer saw. All in all, our knowledge of big cats is quite limited. For this reason, I wouldn't take the information often used all too serious. Let's take India en Nepal. In the last decades, only a few dozen wild Indian tigers (males and females) have been measured and weighed. Of these, two males exceeded a 600-pound scale and two females exceeded 350 pounds. The female in south-west India, not known for large tigers, was no less than 177 kg. (391 pounds). Every time an exceptional animal is mentioned, the 11-feet tape and inadequate scale stories pop up. When a biologists says he weighed a wild male bottoming a 600-pound scale in a peer-reviewed document, the adjustment stories make their way to documents. Many years ago, I was getting bored with what I read. For this reason, I decided to do the administration myself. The conclusion for now is most accepted averages on mass, length and skulls of big cats are inaccurate. Same for the accepted limits (minimum and maximum). The reason is a limited amount of information in most cases and cynicism or preference in others. V. Mazak (1983) is the most reliable, but he dismissed too many records of large animals. Wild Indian tigers, for example, do not average 14 inches in greatest total length but a bit over and wild male African lions exceed 400 pounds empty more often that he suggested. In general terms, however, he was probably the most accurate on length, mass and skull size. The reason? He made work of his ambition to find out a bit more. Furthermore, he used his own data. |
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