Wild-caught specimens have greater difficulty adapting to a captive environment, which can result in refusal to feed, and they generally carry internal or external parasites. Specimens have survived for up to 60 years in captivity, with the oldest recorded ball python being kept in captivity 62 years, 59 of those at the Saint Louis Zoo. Although the popularity of python breeding has led to more captive-bred ball python pets, it is often cheaper to import them from the wild, and tens of thousands are exported from West Africa each year. The conservational impact on the native population is not well documented.