Nadler, R. D., Herndon, J. G., Metz, B. et al. 1992. Environmental enrichment by varied feeding strategies for individually caged young chimpanzees. In: Chimpanzee Conservation and Public Health: Environments for the Future. Erwin, J. , Landon, J. C. (eds), 137-145. Diagnon/Bioqual, Rockville, MD.

Providing an ear of unhusked corn daily or on alternate days, in addition to laboratory chow, resulted in more time spent contacting food [primarily the corn] an hour after feeding [34% & 55%] than feeding laboratory chow alone [8% & 5%]. Seven of eight [single-housed] animals exhibited less stereotypy on the days they received the ear of corn. Stereotypical behavior, which occurs at relatively low frequencies under natural conditions, was reduced somewhat when the animals were fed three [rather than one] meals.