Jelle lived in a Dutch zoo in a group of over 20 chimpanzees. Unfortunately, he killed some chimpanzee babies there and attacked the chimpanzee mothers, presumably due to power struggles. He would have been euthanized as a result. His last chance was with us in the male group. But here too, Jelle inflicted serious injuries on several chimpanzees, so we decided to keep him individually for the benefit of all. He is an extremely intelligent chimpanzee and a passionate nest builder. He comments on food with loud cries of delight and has developed a particular fondness for onions. When Jelle's hatch to the outdoor enclosure opened for the first time, there was no stopping him. He often likes to sit high up in the tree. If he feels unobserved, he tends to try out everything. He tries to loosen nuts and bolts and challenges our keepers, who have to check his enclosure very carefully every day.