From New Scientist:

Willy was never really free. The killer whale star of the Hollywood movie Free Willy had to be cared for by humans even after he was released and he never successfully integrated with his wild kin. Researchers now say attempts to return him to the wild were misguided.

"We believe the best option for [Willy] was the open pen he had in Norway, with care from his trainers," says Malene Simon

of the Greenland Institute of Natural Resources, who participated in efforts to reintegrate the cetacean in the wild and is lead author of the study. "He could swim as much as he wanted to, had plenty of frozen herring - which he was very fond of - and the people that he was attached to kept him active."

The

killer whale, whose real name was Keiko, died in December 2003, at about 26 years old. Despite efforts to integrate him with wild killer whales in Iceland towards the end of his life, he proved unable to interact with them or find food.

"While

we as humans might find it appealing to free a long-term captive animal," the researchers say in the paper, "the survival and well-being of the animal may be severely impacted in doing so." The only cetaceans that have successfully been returned to the wild have been young and only kept in captivity for short periods.

The team's comments contradict those made by members of the Free Willy-Keiko Foundation,

who declared in 2003 that his case had challenged the perception that whales cannot be returned to the wild. But Simon's account of Keiko's last few years shows just how unsuccessful his release was.

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