Forage box as enrichment in single- and group-housed callitrichid monkeys (2005)

Chamove, A. S., Scott, L.

Abstract

When presented with food, common marmosets will more often take it directly into their mouths than use their hands. This might explain why in the conditions where a lid was used, there were fewer forage-related hand movements than might have been expected. Making extraction more difficult, by forcing them to forage with their hands through the openings of a lid, does not increase their foraging time, suggesting that it is the movements, rather than the task, that control the motivation.