From Captivity to the Wild and Back: An Attempt to Release Keiko the Killer Whale
Simon et al., Marine Mammal Science (2009)
Abstract: A number of cetaceans have been released into the wild, with research or the improved welfare of the individuals in question as the main goal. In a few cases, releases have been monitored with methods such as telemetry or photo-identification. As a rule, the animals released successfully into the wild had been captive for relatively short periods of time (e.g., 2 yr) were held in sea pens rather than concrete tanks, and some were released in the company of conspecifics. We describe here the last phases of a project aimed at releasing a single killer whale that had been captured as a calf, raised in tanks and kept isolated from conspecifics during most of his life.
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