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The largest recorded Orca
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Thanks you for the information and the two documents Tigerluver. You are not going to believe in me, but I have downloaded them seconds before you post them here. [img]images/smilies/wink.gif[/img]
Your approach on the "wild vs captive" weight is more deep than mine, because in your logic, wild animals are heavier by virtue of they more developed muscles and denser bones. However, my approach was more general, and of course taking in count the fat. In this case, captive animals are more heavier than wild ones. Check for example tigers, as no tiger is going to weight 400 kg in the wild, but there are a few confirmed specimens of that weight and more in captivity. Gerald Wood (1978) put a huge list of captive and wild mammals and in all cases, captive specimens are heavier. I think is going for interpretations, but overall, a captive specimen, on land, would weight more than a wild one. Obviously, I don't know if this is the same on sea. On the weights of wild orcas, the weights could be obtained from dead specimens, that are normally measured by scientists (not taking in count those measured by lasers and photographs, of course), however, like you say, it will be expensive and time consuming, and that will be the answer about why I have not found any weight in scientific papers. On the other hand, there are the hunting records from the whalers, where many weights came, but again, Wood (1978) explain that those weights are from cut specimens (in the case of the largest whales) and the loss of blood and other fluids create and underestimation of the real figures. 
Well, since even a big cat expert like Nobuyuki Yamaguchi can be sometimes biased or wrong, then the quote from some professional cetacean book can be inaccurate as well.
BTW, based on all the assumption, i personally think a 8 tons wild bull orca will absolutely be considered as a freak of the nature.  (02-26-2015, 09:53 AM)'GuateGojira' Wrote:"Also, the logic about the "wild vs captive" is incorrect. Captive animals are normally heavier than wild counterparts. For example, the largest wild tigers and lions are not as heavy than they largest captive brothers."(02-25-2015, 11:27 PM)'Pckts' Wrote: You can never say what a wild animal can weigh at their maximum. There are 1000s that will never be measured or even seen. In captivity you can monitor the animal for its entire life, you know how old it is, you can compare it to others, weigh it with relative ease, etc. In the wild you can't just capture the biggest orca in the sea and weigh it, its impossible. A captive animal will never be as larger as a wild counterpart. As heavy, maybe, but obese for sure. A wild animal will always be more physically fit, stronger, faster and most likely larger. That goes for big cats as well, look how close the averages are between captive and wild animals. Yet the captive are fat, at least most of them compared to the wild animals. Its always going to be like that, and the same rule applies. You cant just capture and weigh the largest big cat in the wild at the prime of his life, it just doesn't happen but you can with a captive animal.Pckts, I appreciate your comment, but you are mixing things here. Like I said, heavier doesn't mean larger. It means more obese, that is why captive Siberians for example are no larger in dimensions than wild ones. The largest "Captive" orcas are wild orcas. They are the only ones being weighed and they are the only examples you can use. Wild orcas would and are definitely larger in length and I am sure body weight, if the largest Orcas on record are Wild than its only going to make sense the there are wild ones that live off a far better diet, have open ocean to grow that will be larger. There are many "captive" orcas who are smaller than their wild counterparts as well, we are simply cherry picking the largest one ever measured but we cannot do that with wild counter parts. Just like big cats, their are plenty of wild counter parts of captive cats that far outweigh their captive cousins. The alleged 900lb siberian captive cats don't give body dimensions but we know from pictures that they are definitely obese, a wild 700lb cat is going to be the far more impressive specimen, it may be "gorged'' but it will be packed full of muscle and larger in body dimensions most likely. Edit: I see that you discussed this with Tigerluver in regards to not discriminating between fat or not. I get where you are coming from, its just a matter of what we mean by "largest or fittest" etc.
Baikal was probably close to 900 pounds during his prime, and his body size is also prehistoric.
He is also larger than those obese Amur/Bengal hybrids. So not all captive specimens are out of shape, same for the captive orca. (02-27-2015, 12:29 AM)'GrizzlyClaws' Wrote: Baikal was probably close to 900 pounds during his prime, and his body size is also prehistoric. What is his body dimensions? Lets compare him to others captive and wild.
He stands 4 feet tall at shoulder and measures 8 feet in the head+body length.
BTW, we can leave this thread for orca, while discussing the captive big cats in the other threads. (02-26-2015, 11:14 PM)'Pckts' Wrote: "Also, the logic about the "wild vs captive" is incorrect. Captive animals are normally heavier than wild counterparts. For example, the largest wild tigers and lions are not as heavy than they largest captive brothers."Let's take the two points here: 1. Captive vs Wild. 2. Wild breed and Captive breed, for a Wild animal. 1. Overall, captive animals are heavier than the wild animals, that is a fact. However, your approach and that of Tigerluver is more deep that the simple comparison, and I support it at some degree. For example, a wild 600 lb tiger will be "heavier" than a 700 lb captive tiger, without the fat (sorry for the use of cats as examples, but that is our way [img]images/smilies/wink.gif[/img]). That will be true if we take in count that the wild specimen has lived in a harder environment and need of physical fitness and strength, its bones most be stronger and its muscles larger, so it is "heavier" in the deep sense. However, in the overall comparison, the real comparison, we can't denied that the captive specimen is heavier than wild specimen, in the example, by 100 lb and that the fat can't just be ignored, it is the critical point here. Other point is that wild specimens don't reach the weight of the captive ones. Like I said before, the heaviest specimens from wild animals are those breed in captivity, even if we take the Smitsonian tiger of 389 kg, it is still smaller than Jaipur at 423 kg. The same goes to elephants and gorillas, just to mention a few. So, in the real sense, captive breed animals are heavier than wild breed specimens. Now, the question is, this apply to marine mammals too? We could say yes, if we see Tilikum and how fat he is, but the few wild weights that I presented suggest otherwise, although I have not yet found if those "weights" are real or estimations. 2. You still insist in the issue that those large orcas are wild animals. Yes, they were wild animals but they were captured as infants, so they entire grow and development came from captive facilities and that will certainly change its morphology. When you mention "better diet" in the wild, it doesn't mean quantity, but quality. Maybe wild orcas eat better fish and other animals, but that doesn't mean that they storage the same fat level than a captive animals that eat probably less but it contain more "chunk" food and without exercise. Check that a person that eat beef and vegetables and make exercise, is more healthy and weight less than a person that eat only chunk food and make no exercise. So, in overall, captive specimens, captured or not in the wild, most weight more than the wild-breed specimens, taking in count the fat that they storage. Did you remember the example of "Old Tom" and Tilikum? I doubt about this comparison now, because the only source (that I have found) about the weight of Old Tom is Wikipedia, so there is not direct evidence (yet) if he was weighed (post mortem, obviously) or just estimated. This is what I would like to know. 
My point on the size discrepancy might have been missed. My conclusion is under the assumption of a non-fat captive specimen. A seriously obese animal will of course weigh more than even the most robust yet fit of its healthy counterparts. In that sense, like I stated earlier, the heaviest specimen in a species will more likely than not be found in captivity.
Though, for aquatic animals, a thought occured to me. In fish (at least your aquarium species), growth is stunted in low water volume conditions whereby concentrations of toxins (ammonia, nitrate, etc.) are unavoidably greater than the vast oceans (I am quite certain of this saying as well, I've experienced it first hand). Fish grow dimensionally their whole lives, and seem to have a hormonal system which reacts to living conditions such as space and toxin levels. This is known as phenotypic plasticity, where one genome can produce multiple different results based on the environment it is put in. I wonder if aquatic mammals undergo the same stunting based on hormonal reactions to the lack of space, as in no way are those tanks enough for such goliaths of the sea. It's certain that aquatic conditions are more sensitive than land conditions, as there are more chemical factors in water which have a direct effect on life. For aquatic mamals, it's all conjecture, the sample size in captivity is too small and the wild sample size is essentially nonexistant.
Well, that is my point, some orcas that we saw in aquariums are relative fat and other don't, but Tilikum is the extreme as he looks very fat. So, extrapolating the same image to a wild orca, is hard to imagine a wild male orca as fat as Tilikum, and by extension, heavier than him. But as you clearly remember to all of us, the sample size in captivity is too small and the wild sample size is essentially nonexistent (at least in the weight issue).
By the way, here are some very interesting pages about Old Tom: http://www.killersofeden.com/Export2.htm http://www.whales.org.au/policies/old_tom.html It corroborate the length and present pictures, but there is no note about any weight. This other page mention length and weight: http://www.edenmagnet.com.au/story/25631...-a-legend/ Sadly, it don't present any source for its dimensions.
On Tilikum, I might be missing what makes him obese. I compared him to some wild pictures:
 *This image is copyright of its original author  *This image is copyright of its original author He's certainly thicker than the whale in the top picture, but similar to whale in the second picture. How exactly does one gauge between fat and a robust body between orcas? In land animals fat is easy to see, but orcas are so round yet compact. Could his thickness be a characteristic of his ecotype? There are a lot of ecotypes, and each's physique can be significantly different.  (02-25-2015, 09:35 PM)'GuateGojira' Wrote: @Wanderfalke, can you read my entire post again? Stay cool, stay cool. I never intended to be offending. I was just asking and stated, that I might be wrong ;-) Turns out I was wrong. Thanks for the response. I´m cool with you. Can´t see any reason to critisize you. So let´s chill ;-) (02-27-2015, 12:29 PM)'tigerluver' Wrote: On Tilikum, I might be missing what makes him obese. I compared him to some wild pictures:Both of these are females, not males. The first is clearly a captive specimen, you can even see the edge of the pool in the lower right corner. The second seems wild, but she could be pregnant. Here are some wild males:  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author With these few images, I also can't see to much differences, apart from the fact that a wild male orca is MAGNIFICENT!!! Check how strong and powerful are these males!!! [img]images/smilies/biggrin.gif[/img] However, when I saw the image underwater I could see that even when they are so massive, that male doesn't look so "fatty" in comparison with Tilikum. Maybe this wild males could weight "more", thanks to its muscles, while Tilikum and other captive wild-born males could weight "more" thanks to its fat layers.
This image show how captive orcas are measured:
 *This image is copyright of its original author So, the lengths seems to be in straight line.
I won't lie, I don't see much difference in the body, but in the tail, Tilikum is thicker or fatter than the ones Guate posted (but similar to the latter orca in my earlier post), however one would put it. I know in a lot of land animals a fat tail indicates an overweight animal.
On the growth curve, it looks like orcas never stop growing, or are at least growing significantly well into their twenties. That'll make it difficult to put an exact cap on their size. |
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