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Modern weights and measurements on wild tigers
Modern weights and measurements on wild tigers
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Modern weights and measurements on wild tigers
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 (11-09-2018, 10:21 AM)Kingtheropod Wrote: GuateGojira regarding food intake. What is your opinion of the Sunquist figures of food intake. The figures showing food consumption of 14-18.6 kg in a 24 hour period does not necessarily mean they consumed all that in one sitting, meaning that cats could have consumed only 7 kg in one feeding session, and consumed another 7 kg later on in the same day after it digested the previous meal. In other words, the 14 kg daily food intake figure could have consisted of several smaller meals meaning the figures for Sunquist being adjusted to 221 kg (minus 14 kg) could be completely void! In addition, what do you think the correct figure for Sunquist study should be, should we use the 221 kg adjusted figure, or the 235 kg?@Kingtheropod, I am very surprised that you are asking me that question again, specially when you already know my answer. Did you remember that harsh debate with Waveriders about the food intake? Did you remember when I explained the method to bait a tiger in Nepal and why the figure of 14 kg is accurate and may be a little excesive to adjust? Let me tell you again. I explained that baits are put between 6-7 pm and latter they are checked again at about 4 am of the next day (in some cases they were checked trought the night at Tiger Tops, as Dr McDougal took turist to see tigers eating baits in the night). This means that the baits are left in the field about 9-10 hours. Of course, there is no case showing a tiger killing a bait inmediatelly after the scientist leave it in the field. So assuming that the tiger manage to kill the bait at about 8 pm, this means that the tiger (male or female) had about 8 hours to eat. Now, tigers do not eat the prey inmediatelly after killing it, it grab its prey and move it to another place and latter it start to remouve all the hair before to start eating. Schaller says that after 1 1/2 -2 1/2 hours eating they stop and rest, maybe they can move to drink something and then return to the kill latter. This means that the tigers (male and female) do not eat constantly with out interruptions during the 8 hours, in fact, they probably eat about 6-7 hours in displaced periods, maybe less, and the other time they rest, drink, play or fight scavengers from the food, that is a normal sesion of feeding for a tiger. Sunquist (1981) found that a tiger (male and female) may eat between 14-19 kg in 24 hours, from baits and also natural kills. However these figures are from undisturbed kills and were measured from several days. Figures of 30-35 kg for male and female tigers do exist, but these are exceptions, not the rule in any case. The tigers at baits only had about 7 hours to feed, maybe 8 in the best case, and Dr Sunquist himself describe that in all the captures they disturbed the tigers at the kills, and in an email he especifically said that he "don't ever remember been struck by the size of the stomach of any of the animals, suggesting that they had not yet eat their fill when captured". So, tigers did not had 24 hours, nor even 12 hours to eat at baits, which means that the figures of 14-19 kg may be actually higher than the real food intake of the tigers in the captures at "disturbed kills". If a tiger eat an average of 19 kg in a day, this means that in 7-8 hours it may eat about 5.5-6.3 kg, which is close to the 6-7 kg that Sunquist (1981) estimated was the necesary daily intake for a female tiger, obviously will be more for a male. Even if we take the figure of 27 kg reported by Dr Schaller from only one male that he was able to measure, it means a food intake of 8-9 kg in the 7-8 hours when the tiger was able to eat undisturbed. Finally if we take the exceptional food intake of 35 kg reported by Dr McDougal, we can estimate a food intake of 10-12 kg for a large male, but this was an exceptional case and represent the maximum food intake, actually measured, reported in litterature. So we can see that about 8 kg for females and 10 kg for males will be a good food intake, assuming that the tiger did eat the 7-8 hours at the kill "undisturbed" (but the "real" feeding time could be much less). Also remember that tigers were captured in the morning and the search for the tigers started at about 5 am and it seems that tigers were found resting, not eating, at the baits, they were not gorged and the food intake was probably less than 11 kg in both males and females in the time that they were at the kills. Please take in count that we are assuming that tigers killed the baits just a few hours after they were put in the field, which probably was not the case. So the figure of 14 kg to adjust the weight of the Nepalese tigers is actually slightly higher than the estimated "real" amount of food consumed by the tiger in the baits "undisturbed", and the figure of 19 kg will be excesive. I can say that the average figures of 221 kg for males and 130 kg for females "adjusted" seems reliable, but could be actually a little higher, maybe up to 227 kg for males. 
Thanks for the reply. I really cant remeber asking you this before, maybe its been a long time.
(11-10-2018, 01:26 AM)Roflcopters Wrote: @GuateGojira @Roflcopters, I am very surprised for you answer, is very harsh and shows something that I did not expected from your part. But let me take the two points separatelly. About the male of 170 kg from Bhutan, you may be right, a tiger killing cattle may be in bad conditions, but somethimes they are actually fat. The article do not mention any details about its health status and that is why I want to investigate this case. Remember that is always good to have all the information posible. You must remember that when I contacted the Russian scientists about some weights of male Amur tigers in news reports and even "official" documents, it resulted that the weights were incorrect and animals that were described to weight 220 kg and 250 kg, at the end they weighed only 182 kg and 200 kg respectively. Now about your concern about the credibility of the sources, this is not the first time that this is discussed in this forum. In fact, I am very aware that those communications may be very reliable, but you need to understand that the information that we have here is also used in other forums and webpages. You need to be very aware that were are been whatched by other people, specifycally in Carnivora, and a couple of posters there are just waiting for the next error to attack us again, that is something that we must avoid. The comment about the reliability was broght by @Dr Panthera (a reliable poster from my point of view) not by me. In fact, I normally used all the figures available to made my tables. However, during all this time, I learned that those webpages and Facebook conversations need to be verified. In any moment I am been arrogant or I am insulting anyone. For the contrary, I only suggested that when a weight is not "officially" published, it reliability can be put in doubt by any person, specially those that are whatching us in other forums. You need to remember the cases of weights of up to 280 kg reported in news papers from tigers in Ranthambore or other sites, but at the end those figures were just mere estimations. Also are all those reports that contradict between them about the weights of the same tiger and many of the reports in this topic don't even describe the sex of the specimen! That is why we need to corroborate ALL the available figures, the more information the better the data. A good example is when the weight of 240 kg for tiger Ustad was actually corroborated trough email, so we can use it. I hope that you can understand my point of view and I am 100% sure that I am not the only one that think in the same form (the same can be applied by the lions, jaguars and leopards). We need to understand that the accuracy need to be very important. If not, we can suffer another case like the famous lion of 272 kg that was attacked so many times in AVA and at the end it was reliable. We need to learn from our previous errors and in the case of all the "modern" weigths and measurements from tigers reported here, is important to corroborate all of them. I invite you, togheter with @Pckts, @Kingtheropod" and @peter to understand my point of view. About my tables, I will include (for the moment) only the weights reported in documents, scientific litterature and those corroborated by emails of the scientists involved. If this offend you, with all the respect you are free to discard my work and make your own. In fact any poster here is free to do and fell as they please.
May I suggest making two tables? One with verified sources only and another without.
I will be gathering all the sources posted here soon, so we can organize them and figure out where to place them.   Notice at .37 seconds of the video, they are measuring this Tigress in a straight line. 
I need information about the tigers weighed in the following chart by @GuateGojira!
 *This image is copyright of its original author I'm asking about 222kgs average for Bengal tigers. In which age class are the tigers being weighed? Because being sexually mature doesn't mean they're fully grown. Also I remember once @Pckts said he takes only 7 year old tigers as adults. So was these tigers are at the age class of 7 years? If not, what would be the average for tigers in northern India and Nepal at the age class of 7 years!
I'm not sure when I said that but it's possible. As of now I don't feel that way though, I consider a Tiger to be fully mature by 4-5 but they do continue to put on size up until 7ish I'd say. But a 4-5 year is coming right into his prime and will be competing for territory at that point so he should thus be considered an adult.
Tigers will be like any other living creature, some will mature early and others will take longer to blossom. To make it easy, consider a human being for a second, some humans stop growing before they turn 18, others say they even grew a couple of inches in their early 20s. Most humans will stop growing vertically at that point but their body will begin to fill out but once they hit a certain age, they begin to lose muscle mass, this usually happens for males in their early 30s. What I'm saying is that I consider a Big Cat an adult at 4 years of age, I consider a Big Cat to be fully grown and in their Prime around 7 years of age and I consider them to be past their prime at 10 years of age. (12-18-2018, 09:35 PM)Panther Wrote: I need information about the tigers weighed in the following chart by @GuateGojira! Those averages take all the specimens labeled as "adults" from modern studies. Most of the sources state that an "adult" tiger is any specimen that is 3 years old or older. The youngest specimen, with known age, is a male from Ranthambore of 220 kg and 3.5 years old. Please take in count that this average do not include the new weights posted in this topic as it predates them (the image was created before those weights were known in the forum). A new study states that just the males over 4 years old are adults, but this paper is from 2016 - 2017, all the other old documents take tigers of 3 years old or older as "adults". Is not a secret that I am not agree with that, as a tiger of that age are still under develpment and is not fully grow. Now, I got a new average figure of 220.8 kg from 21 males (range 184 - 261 kg), but includes only those published in scientific papers and corroborated by me. If we include all the other males in this topic (which I will do soon), the average will be higher. For females, I have a new average of 137.6 kg from 30 specimens (range 102 - 177 kg), again this includes only the specimens in scientific papers and those corroborated by me. If we include those from this topic the average will be probably higher. I excluded the weight of 85 kg from a Tadoba female for good reasons, I will explain them soon. Hope this helps. (12-18-2018, 09:54 PM)Pckts Wrote: I'm not sure when I said that but it's possible. As of now I don't feel that way though, I consider a Tiger to be fully mature by 4-5 but they do continue to put on size up until 7ish I'd say. But a 4-5 year is coming right into his prime and will be competing for territory at that point so he should thus be considered an adult. I forgot the thread, but I remember you talking that with someone like "Grizzlyclaws" or "brotherbear". Of course it is possible. Actually male tigers reach sexual maturity at 4-5years. "Females reach sexual maturity at 3-4 years, whereas males reach at 4-5 years". Source: Walker's Mammals of the World (6th ed.). Baltimore: Johns Hopkins University Press. pp. 825–828. Another source: https://books.google.co.in/books?id=f-Fy...s.&f=false So, how can a 5 year old tiger counted to be "fully grown", where that is when they reach sexual maturity? I have to get it clear, because reaching sexual maturity isn't equal to "fully grown"! (12-19-2018, 10:24 AM)GuateGojira Wrote: Those averages take all the specimens labeled as "adults" from modern studies. Most of the sources state that an "adult" tiger is any specimen that is 3 years old or older. The youngest specimen, with known age, is a male from Ranthambore of 220 kg and 3.5 years old. Please take in count that this average do not include the new weights posted in this topic as it predates them (the image was created before those weights were known in the forum). A new study states that just the males over 4 years old are adults, but this paper is from 2016 - 2017, all the other old documents take tigers of 3 years old or older as "adults". Is not a secret that I am not agree with that, as a tiger of that age are still under develpment and is not fully grow. I don't think 4 year old tiger is fully grown, where that is when they reach sexual maturity. What would be the average, if the tigers are at the age class of 6-7years? I guess it'd be 250-270kgs. But assumptions are assumptions, no one believes. Can you please make a chart based on 6-7 year old males @GuateGojira? I think you have enough information to make it! (12-19-2018, 03:04 PM)Panther Wrote: I don't think 4 year old tiger is fully grown, where that is when they reach sexual maturity. In fact, the document of Y. V. Jhala & A. Sadhu "Supplement Appendix 1: Field Guide for Aging Tigers" from 2017 states this: * Cubs (<12 months) * Juveniles (1 to 2 years) * Sub-adults (>2 to 3 years) * Young-adults (>3 to 5 years) * Prime-adults (>5 to 10 years) * Old-adults (>10 years) So this is, for the moment, the better guide to age tigers. The scientists from the Siberian Tiger Project (USA) included all the specimens over 3 years old as "adults", but its list includes those that were clearly not fully grow and some were even in bad conditions, that is why they got an average of only 176 kg. My average of 190 kg includes the males from The Amur Tiger Programme (Russian) too and although it still includes some males of over 3 years old (following the STP protocol) it excludes the unhealty males. Now if we take only the males over 5 years old, certainly the average will be slightly higher. Creating a table of "only specimens over 6 years old" is complicate, mostly because some of the weights are just labeled as "adults" and do not state its age. Is posible to do it, but will have a little of assumption on it. (12-20-2018, 07:43 AM)GuateGojira Wrote: In fact, the document of Y. V. Jhala & A. Sadhu "Supplement Appendix 1: Field Guide for Aging Tigers" from 2017 states this: That's right. "* Young-adults (>3 to 5 years) * Prime-adults (>5 to 10 years)" This is what I'm talking about. 5-10 years means roughly 7years. That is the age of being fully grown. Alright Guate, take your own time. But create a table for 6-7 year old adults for Bengal tigers.. thank you!  (12-20-2018, 07:43 AM)GuateGojira Wrote:(12-19-2018, 03:04 PM)Panther Wrote: I don't think 4 year old tiger is fully grown, where that is when they reach sexual maturity. In the last two years we have managed to gather some new & reliable info in the forum. New studies have been done as well! If you have time, could you redo an update of the Bengal & Amur male tiger weight chart taking the age limit as 4 to 12? That is roughly the common age range of resident males with territories, including some young & older adults too. Problem solved... |
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