Rockhampton Zoo's baby chimp reintroduction attempts end in aggression

In June, the Rockhampton Zoo welcomed a newborn chimpanzee named Cassie, whose mother Sile accidentally dropped her, causing a broken leg that required intensive hand-rearing by keepers. After the injury healed, staff arranged a reunion through a screen, observing encouraging signs before attempting a direct introduction, which was halted when Sile showed aggression toward Cassie. A second trial with Mary, an adult female who had given birth to stillborn twins earlier this year, also turned hostile, leaving Cassie with bruises and bite marks.

Throughout this period, keepers have been mimicking natural chimp behavior, feeding Cassie by bottle every three hours and using a custom-made “chimp vest” to encourage clinging. Curator Blair Chapman emphasized that hand-raising is a last resort and that the team continues to discuss options with global primate specialists, though no decision has been reached yet.