What Happens When Captive Animals Are Released?

After they've been in captivity, do animals fair better in their natural habitat?

Related on TestTube
7 Pets You Should NEVER Release Into the Wild
The Pros & Cons of Zoos

Animal activist group PETA is calling for the release of an orca whale named Lolita from a Florida aquarium. That got us wondering: how do captive animals fair once released in the wild? Trace talked about pets you shouldn't release into the wild, but what about wild animals? Do they do better in their natural habitat after they've been in captivity? Some captive breeding and reintroduction programs are really important for conservation efforts. Programs like this have seen the successful return of species like the black-footed ferret, bison, peregrine falcon, and more. A more recent study by the International Union for Conservation of Nature found that most release programs work: Of the 67 releases they reviewed (consisting of all sorts of animals--from orangutans to parrots, fish, and frogs--13 were deemed "highly successful", 28 were "successful", 25 were "partially successful", and one was judged a "failure". Success was tied strongly to the species and the place: fish tended to fair better than mammals.

A 2008 study published in the journal Biological Conservation found less promising results: their study showed that the odds were against reintroduced carnivores. Of the 47 case studies reviewed of 17 different carnivore species, researchers found that only 33 percent survive. Over half of those deaths were a human's fault, either by hunting or car accident. Despite the disappointing results, the authors were optimistic. Kristen Jule, one of the study's authors said she believed "reintroduction projects are vital to conservation efforts". The study recommends restricting contact with humans and improving captive habitats. Basically try to raise young animals in an environment as close to the wild as possible, so they can learn to live and hunt on their own.

Currently two Indo-Pacific bottlenose dolphins, Taesan and Boksoon, are being reintroduced to the wild again. They were illegally caught a few years ago and after a prolonged legal battle, they've won the right to be free after five years in captivity. In order to ensure their survival, they're being put through a "wild rehab", where researchers limit their contact with humans and learn to hunt again. They're not the first: five other dolphins have been through similar "bootcamps" and while some have successfully joined wild pods, they might be the last: it's incredibly expensive to release large marine mammals and as long as marine parks exist, they'll want to keep their stars of the show.

Learn More:
Global Re-introduction Perspectives: 2013 (ICUN.org)
"Out of the seven major taxa only invertebrates did not have a project ranked as highly successful. There was only one amphibian case study and this was ranked as highly successful."

Captive Carnivores Not Up To Wild Living (Science Daily)
"On average only one in three captive-born carnivores survives in the wild, with most deaths related to human activities."