Finding better homes for captive orangs.

To discourage an illegal pet trade in orangutans, Indonesia has confiscated hundreds of the animals over the past few decades. Now, lacking funds to maintain them all, it has to figure out what to do with the captives.

Rehabilitation has long been considered a humane option. Confiscated animals have been sent to holding centers in Malaysia and Indonesia, the only places with native populations, where scientists initiate a lengthy and costly program to prepare the animals to rejoin their wild kin.

Now, a study by primatologist Carey P. Yeager of Fordham University in Armonk, N.Y., finds that "despite the best of intentions," reintegrating most captive orangutans into wild populations just doesn't work.

Yeager studied the fate of 27 animals released at Indonesia's Tanjung Puting National Park rehabilitation center in 1981 and 1982. As of 3 years ago, only 11 were definitely known to be alive, she reports in the June CONSERVATION BIOLOGY. Since many animals remained strongly dependent on the center for food after their release, a sudden, prolonged absence suggests that they have succumbed to injury or disease.

Inappropriate behavior compromises the released orangutans' survival. Most had been captured in infancy, long before finishing some 7 years of schooling by their mothers in foraging and other ways of the wild. The naturally solitary animals, which can live 60 years, also become abnormally sociable in captivity--a trait that fosters contact with people and unwelcome, even violent interactions with wild orangutans.

Zoos aren't a viable alternative, because the birthplace of most captives is uncertain--and zoos no longer combine orangutans taken from different areas (SN: 3/25/95, p. 184). So rather than mixing behaviorally incompatible animals, Yeager recommends that governments release captives to forested areas where no wild orangutans exist. "As ex-captives are a major tourist draw, it might be possible to completely fund the feeding and maintenance of [these animals] and provide funds for protection of the wild population through eco-tourism."