The largest recorded Orca

[GuateGojira]

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.
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