"The shock goes deep," head zoo keeper Walter Wolters said on Thursday of orangutan Leila's death. The other orangutans are inconsolable, he added. "Leila's mother Mokko refused her breakfast and is looking everywhere for her daughter." The two had an especially close relationship, he said.
An unidentified visitor disobeyed zoo rules on Wednesday and threw a piece of bread that landed in a water enclosure. Ten-year-old Leila tried to retrieve the bread, but fell into the water instead.
"Like all primates, she couldn't swim, and sank immediately," Wolters said, adding that her thick fur saturated quickly, weighing her down even more.
The endangered orangutan's death is particularly tragic for the zoo because she was intended for breeding.
There is no trace of the person who threw the bread.
Zookeepers await Leila's autopsy report, after which her body will be given to the University of Hamburg for research before she is stuffed and displayed, Wolters said.
Orangutans are native to the rain forests of Indonesia and Malaysia. They live to be up to 30 years in the wild, and up to 50 years in captivity.