Dorsal Fin Collapse
March 2nd, 2009
Interesting and sad story for today. This is why I’m against animal entrapment (zoos primarily). Other than the dog and cat which evolved symbiotically with humans, all other animals deserve to be free. Like that chimp that attacked last month, animals in captivity are not happy as any caged human wouldn’t be either. It’s simply torture and abuse but we all need our amusement, don’t we?
There’s a lot of BS intellectualizing about why the dorsal fin of dolphins and killer whales collapses in captivity but I believe the answer is much simpler:
It is due to stress and mental knowledge of being captive. They show the same behaviour when they are locked in a lagoon or cove and can not get out to the open ocean.
Source(s):
Life in Alaska
I always thought it was because of injury at some point. But I s’pose it could be just cos it’s unhappy!
July 30th, 2009 at 9:31 pm
I’m with you on not keeping orcas/killer whales in captivity. Sadly, the whales that are currently in captivity are unlikely to be successfully reintroduced to the wild. Keiko’s release (he was the whale from “Free Willy”) was not particularly successful. He was unable to reintegrate into any new pods, and he eventually died from pneumonia after a year of continuing to be fed by humans in an isolated Norwegian bay.
There’s a pretty decent explanation for why a high percentage (as high as 90%) of captive male orcas develop collapsed dorsal fins. The most plausible explanation is that the fins are designed to stand straight under circumstances of frequent uniform pressure. The uniform pressure of deep water against all surfaces of the fin keeps it in its original position. Captive whales are in shallow pools and spend a fair amount of time close to the water’s surface. Over time, gravity takes over, and the cartilage becomes weak and collapses. This site discusses several theories and sources the information: http://en.allexperts.com/q/Wild-Animals-705/Orca-Killer-Whales.htm
Something I found curious though was the comments of those who released Keiko into the wild: “We have … learned that we were wrong about some things. We thought Keiko’s signature dorsal fin, flopped to the side, was the result of captivity, until we found wild North Atlantic whales with the same fin. It remains to me the emblem of how little we know and how arrogant are our attitudes to think we have nature figured out. Perhaps more than anything, I have learned from Keiko that we know so very little about the wild sea and the dynamics that keep it healthy.” From: http://www.oceanfutures.org/features/2003/dispatch_12_16_03_keiko.php