In 1985, a young male orangutan peacefully strolled out of his enclosure at the San Diego Zoo and casually wandered among the patrons. Keepers scrambled to figure out how he escaped the highly secure Heart of the Zoo exhibit.
They raised the walls, smoothed the surfaces, and stacked cinder-blocks to remove handholds. It didn’t matter. The orangutan, named Ken Allen, simply continued to outwit his captors and casually walk out into the park, launching a years-long battle of wits between man and ape.
A Master of Observation
Ken Allen was born in captivity at the San Diego Zoo in 1971. He established a reputation early on in the nursery by unscrewing every nut and bolt he could find. As an adult, his escapes stumped the zoo administration. After Ken’s initial breakouts in the summer of 1985, the zoo added electrified wires to the perimeter of the enclosure.
Rather than giving up, the orangutans observed the system. Ken eventually figured out how to wait until the power was temporarily shut off during maintenance. His female companions also joined in. A female orangutan named Kumang learned to actively ground the hot wire using sticks and pieces of wood before pulling herself up by using the porcelain insulators as hand-holds.
Spies and Rock Climbers
The zoo’s countermeasures grew increasingly desperate and expensive. Officials dressed up in Hawaiian shirts and sunglasses to spy on the apes, hoping to catch them in the act of planning an escape. However, Ken immediately recognized the undercover keepers and refused to reveal his methods while they watched.
In 1987, the facility hired professional rock climbers to scale the enclosure walls and eliminate every possible microscopic finger and toe hold. The zoo placed the orangutans in solitary confinement and budgeted $45,000 for a massive overhaul. Administrators even paid contractors to sweep the entire enclosure with high-powered magnets to confiscate any hidden tools the apes might have stashed.
The Hairy Houdini Becomes a Star
Ken Allen’s persistence turned him into a local and global phenomenon. Dubbed “The Hairy Houdini,” he gained his own dedicated fan club. Zoo patrons bought T-shirts and bumper stickers reading “Free Ken Allen,” and a musician even wrote a song titled “The Ballad of Ken Allen.”
Despite the zoo spending tens of thousands of dollars completely redesigning the enclosure—rounding every corner, installing new doors, and ripping out the old hot-wiring for a more advanced system—Ken and his female companions continued to find ways out. The escapes remained a constant source of frustration for the administration and a point of amusement for the public. Ken Allen remained at the San Diego Zoo for his entire life until he developed B-cell lymphoma and was euthanized on December 1, 2000, at the age of 29.