This group of lemurs had been housed together in this
enclosure since 2000 and previously had been offered a
number of different kinds of enrichment, so a novelty effect
of enrichment was unlikely. Based on observations prior to the
experiment, none of the study animals engaged in obvious
stereotyped behaviors, but they appeared to spend much less
time foraging and moving than is typical of wild lemurs. In
addition, study animals were observed to pirate food as noted
above, by removing items from the feeding stations of the
hyrax and porcupine. This behavior is both uncharacteristic of
wild lemurs and may have contributed to weight problems for
the lemurs, which were heavier than published values for wild
individuals (unpublished data, Santa Ana Zoo