|
The largest recorded Orca
|
Most websites commonly cited the 9.8 meters individual caught off the coast of Japan as the largest specimen ever recorded.
Does anyone here know its exact weight? And if it is a reliable source? 
Hmm, Ill have to look into this. I would assume like with the GWS, there are some much larger ones out there, we will probably never know for sure.
(02-25-2015, 04:25 AM)'Pckts' Wrote: Hmm, Ill have to look into this. I would assume like with the GWS, there are some much larger ones out there, we will probably never know for sure. Since most captive bull orcas rarely reached 6 tons, so it is hard to believe that this Japanese specimen was over 8 tons, or even 10 tons. (02-25-2015, 04:26 AM)'GrizzlyClaws' Wrote:(02-25-2015, 04:25 AM)'Pckts' Wrote: Hmm, Ill have to look into this. I would assume like with the GWS, there are some much larger ones out there, we will probably never know for sure. Captivity is meaningless. Just look at how they are treated at sea world. Trying to compare the open ocean and all of its treasures to a small tank being fed the same crappy food for their entire life is never going to show the capabilities of that animal. 
Talk about the records of marine animals is very difficult, specially by the fact that the scientific investigations in this area are few and most of them not invasive. Most of the records came from hunters (fishermen and whalers), which are famous for they exaggerations.
Normally, in most books you will found the record of the male orca of 9.8 m of Japan, other sources add a weight of 8-9 tons for it and other even 10 tons. However, the only source that state a reference is Nowak (1999), check it out:  *This image is copyright of its original author I bet that most sources use his data as the main source, however he never stated that the largest weight corresponded to the largest length. Besides, I am till unable to found the "original" source of the data (Scheffer, 1978 b.), which make me doubt about the reliability of it. Normally, wild orcas are say to average about 6-7 m long in males, but this apply to the resident group. Transient groups are slightly longer but the other types are smaller, with about 5-6 m on average. Of course, most of this data is based in estimations and not direct measurements. On the captive specimens, I think that even under they bad conditions, the largest specimens are pretty large and even with some overweight. The largest orca ever held in captivity is the famous "Tilikum", with a length of 8.2 m (27 ft; measured in 2012) and a weight of 5,443 kg (12,000 b; taken in 2008). These are the official measurements (don't ask me how they were taken, the source don't mention it), and the animal itself seems very fat, not as slender (relatively speaking) as its wild counterparts. Just a few images to make comparisons:  *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 Please, take in count that in ANY moment I am saying that they live in perfect conditions, for the contrary, the documentary "Black Fish" is mandatory to understand the bad (and even horrible) conditions that some of these animals live every day. In the case of Tilikum, he was raised like a stallion, with the best food (he is fat) but used lake a semen storage for captive reproduction. Now, after the death of 3 people, he is isolated for human contact, as far I remember. Well, the point is that the records from wild orcas that I have see present maximum figures of between 7 to 8 meters long, about the same than the captive specimens. However, I have not see any study with weights of wild orcas, and taken the captive specimens as surrogates, it seems that wild orcas will reach maximum figures of 4 to 5 tons, in the higher side. It is too early to reach any conclusions, Pckts and GrizzlyClaws will surely present more data, which will add more information on the issue, so I leave this just as an introductory post and not as a conclusive one, at least from my part. I remember a study where they presented a list of lengths from wild orcas, I will found it just for comparison purposes.
The longest alleged Orca specimen was 32 feet, so even it is true, then it is more likely 6-7 tons than 10 tons.
Since we got a great comparison example like Tilikum, who was much more overweighed compared to its wild counterparts.
Here is another record from Gerald Wood and his book "Animal Facts and Feats" (edition of 1982):
 *This image is copyright of its original author It seems that "Orky" was slightly shorter but heavier than "Tillikum". The problem is that in this case, it is clear that the weight was estimated (I don't have data about Tilikum, but I think he was weighed directly. In the edition of 1978, Wood cited other two captive specimens that were trained by military purposes: 1. Ahab: 5.79 m (19 ft) long and 2494 kg (5500 lb). 2. Ishmael: 5.18 m (17 ft) long and 2041 kg (4500 lb). This other captive specimens can help us the give an idea of the length-weight relation in orcas. Here are other picture of Tilikum, where you can see its huge size and fatness: *This image is copyright of its original author  *This image is copyright of its original author This image show how the orcas are weighed in captivity, which direct me to think that Tilikum (and other captive specimens) were actually weighed.  *This image is copyright of its original author This other image show another way to weight orcas:  *This image is copyright of its original author "Currently, the EWS product line includes truck and track scales, tank and hopper scales, floor and bench scales, tension measurement systems, process control weighing systems, and a variety of custom designed weigh systems. The picture below shows a killer whale sliding up on a 9 by 15 foot platform scale designed to hold up to 40,000 pounds." Check this link, there is the explanation: http://econintersect.com/b2evolution/blo...f-made-man This show that is perfectly posible the weight an orca in captivity.
Is Tilikum 27 feet or 23 feet? Since some source suggests that he is only 23 feet.
BTW, it is possible that Orky was even fatter than him.
Here is an excellent page about the size and weight of captive orcas, sadly some data (like that of Tilikum) is not actualized:
http://www.orcahome.de/orcastat.htm These are captive specimens, but at least, are somewhat useful for comparison. Here is the page of Tilikum: http://cetacousin.bplaced.net/captive/or...likum.html Sadly, for reasons that I don't know, the link doesn't work for me now. However, here are the screen shoots that I take previously:  *This image is copyright of its original author  *This image is copyright of its original author The latest measurements show a size of 27 ft (8.2 m) long and a weight of 12,000 lb (5,455 kg), and this seems to be an exceptional specimen. Finally, here is a grow curve of orcas, based in captive specimens, this will help you a lot:  *This image is copyright of its original author Somehow, based on this data, I think that a large orca will probably measure about 8 m long and about 5 tons in the wild. A specimen of 9-10 m will be exceptional and will top about 6-7 tons, but that is just a simple appreciation.
I see, a male Orca like Tilikum must keep growing until the age around 30, but his weight probably remains at 12,000 pounds.
I think he probably went to a diet in order to make himself healthier.
I don't think that Sea World had put Tilikum to diet, more posible is that in the last exam, he was not weighed and only measured. 2005 was the last year were they took both measurements.
By the way, I found this interesting paper about the situation of captive orcas: https://theorcaproject.files.wordpress.c...tivity.pdf This is not the point of the topic, but I would like to share it with you.
If he is not on a diet, then he will definitely top 14,000 pounds by now.
I can imagine that the largest wild bull Orca is probably few feet longer than Tilikum, but the weight is probably the same since Tilikum is considerably more overweighed.
Yeah, I agree that a wild larger orca will weight the same. Now, on the weight of Tilikum, we don't know how much weight him not, probably, at 2015, he could gain more weight than in 2008. All the references about its weight are old now.
Just for comparison, here is the data of a wild orca known as "Old Tom": http://en.wikipedia.org/wiki/Old_Tom_%28killer_whale%29 This article say that "Old Tom measured 22 feet (6.7 m) and weighed 6 tons. The skull measured 1.02 m and the teeth measured about 5.31 inches (13.4 cm)." However, again, no source is given, unless than the first source also was the reference for the size reported here. Here is more information of the grow of the orca:  *This image is copyright of its original author Duffield, D.A. and K.W. Miller, 1988. Demographic Features of Killer Whales in Oceanaria in the United States and Canada, 1965-1987. Rit Fiskideildar. 11: 297-306. In Pacific whales, growth is approximately linear, at a mean rate of 38 cm/yr up to 10-12 or 12-16 years of age, for females and males, respectively. Source: http://www.orcahome.de/growthrate.htm
I think 5.31 inches is probably the largest tooth measured for Old Tom, and definitely including the root.
Since the largest Orca tooth i've seen is probably around 6-7 inches and weighs about 7-8 ounces. 
Wild orcas live much longer and are infinitely healthier than their captive counterparts. I do believe a 32'
orca can possibly top 20,000 lbs. Their mass increases dramatically as their length does. If a 20' orca can weigh 8-10,000 lbs, an addition 10-12' in length would easily double their weight and thensome. |
| Users browsing this thread: |
| 2 Guest(s) |