"People should not think that sudden freedom for a captive animal means what it would to a captive human," said Alexandra Dixon, London Zoo's leading reintroduction expert. "To an animal, it means it's suddenly got all the stresses of life in the wild directly on it. Life in the wild is tough. It means the animal has to fend for itself, and lunch is no longer at two o'clock unless it finds it."
Captive animals need long and careful preparation before release, and monitoring and help afterwards if they are to survive, said Ms Dixon, director of field conservation and consultancy for the Zoological Society of London. And their chances are best if they are part of a social structure.
The zoo is involved in two successful reintroduction programmes, with sand gazelles in the Empty Quarter of Saudi Arabia, where they had become extinct 40 years ago, and with black and white ruffed lemurs, which are declining in their native Madagascar.
"There does need to be a great deal of preparation," Ms Dixon said. "It doesn't need to be cost and labour-intensive. It's mainly thinking. What do we need to do to maximise the animal's chances in the wild? Some species need training, to avoid predators, for example."
The zoo deliberately created social groups of the gazelles before release. "Social structure is very important," Ms Dixon said. It is a concern shared by the British group that has been supporting the campaign to return Keiko to the wild, the Whale and Dolphin Conservation Society.
"Social structure among orcas is very flexible," Fran Clarke, the group's campaigns co-ordinator, said.Reuse content