have been reintroduced to the wild. Released animals are commonly less capable of hunting or foraging for food, which leads to starvation, possibly because the young animals spent the critical learning period in captivity. Released animals often display more risk-taking behavior and fail to avoid predators. Golden lion tamarin mothers often die in the wild before having offspring because they cannot climb and forage. This leads to continuing population declines despite reintroduction as the species are unable to produce viable offspring. Training can improve anti-predator skills, but its effectiveness varies. Salmon bred in captivity have shown similar declines in caution and are killed by predators when young. However, salmon that were reared in an enriched environment with natural prey showed less risk-taking behaviors and were more likely to survive. A study on mice has found that after captive breeding had been in place for multiple generations and these mice were "released" to breed with wild mice, that the captive-born mice bred amongst themselves instead of with the wild mice. This suggests that captive breeding may affect mating preferences, and has implications for the success of a reintroduction program. Human mediated recovery of species can unintentionally promote maladaptive behaviors in wild populations. In 1980 the number of wild Chatham Island Black Robins was reduced to a single mating pair. Intense management of populations helped the population recover and by 1998 there were 200 individuals. During recovery scientists observed "rim laying" an egg laying habit where individuals laid eggs on the rim of the nest instead of the center. Rim laid eggs never hatched. To combat this land managers pushed the egg to the center of the nest, which greatly increased reproduction. However, by allowing this maladaptive trait to persist, over half the population were now rim layers. Genetic studies found that this was an autosomal dominant mendelian trait that was selected for due to human intervention Successes The De Wildt Cheetah and Wildlife Centre, established in South Africa in 1971, has a cheetah captive breeding program. Between 1975 and 2005, 242 litters were born with a total of 785 cubs. The survival rate of cubs was 71.3% for the first twelve months and 66.2% for older cubs, validating the fact that cheetahs can be bred successfully (and their endangerment decreased). It also indicated that failure in other breeding habitats may be due to "poor" sperm morphology. Przewalski’s horse, the only horse