People always say they’ll never be able to reestablish themselves in a wild setting. But seriously, come on, these are animals that run on instinct and calculated actions; taking them out of the wild is not going to render them incapable of relearning natural behaviors. They don’t just go “HeRp DeRp I fOrGoT hOw To WhALe”.
I honestly believe, depending on the social dynamics of the animals, most marine mammals can be released. I think the only problem with Keiko’s release was that we didn’t know his original pod, and therefore, the Orcas he socialized with probably weren’t related to him.
With Lolita from the Miami Seaquarium, it’s a different story. We know her family and her probable mother. Same goes for Morgan at Loro Parque.
With Kshamenk, he’s a “transient” Orca, more than capable of taking care of himself.
If anything, Tilikum, Ulises, Kasatka, and all other wild caught Orcas probably could experience the same thing Keiko did [Or at least, retirement to a natural ocean pen].
And regardless of the situation, Keiko died a free Orca. His death was entirely unrelated to his interaction with people/lack of interaction with other Orcas. In my opinion, Keiko’s release was indeed a success.