The capuchins are a free ranging group, i saw them being feed and spoke to a keeper. Capuchin monkeys are not native to mendoza province, it is too dry for them. Capuchin monkeys do live in the nortern argentina near brazil.
Thanks for clarifying. Someone who previously worked at the zoo told me that they were likely escaped animals which had settled on site. This place has one of the highest densities of free-ranging animals on site, so it was sometimes difficult to establish what had escaped and what (if anything) had been left to roam free, or was wild.