Steen, Z. 1995. Effects of enriched food acquisition on activity budgets of two tamarin species at Adelaide Zoo. International Zoo News 42, 284-298.

Simple bamboo pipe feeder is described and tested in group-housed animals. The aim of the study was to [successfully] increase foraging time with an increasing number of feeding devices [brawn bowl, bamboo pipe]. ... Prior to the study large amounts of fur were found in the nesting box of the golden tamarins. The zoo vet suspected that this was a result of overgrooming. During and after the study the overgrooming apparently ceased because the animals had something else to do.