orangutan3An orangutan at an Australian zoo has been placed in solitary confinement following a remarkable escape attempt in which she short circuited an electric fence with a branch and then built a ladder from shrubs and sticks to scale another wall – before abandoning the bid for freedom and returning to her pen.

Zookeepers at Adelaide Zoo believe Karta, 27, may have been looking for her mate, Pusang, who died of a respiratory infection a month ago. The zoo had to be evacuated and closed Sunday amid dramatic scenes as Karta broke out of her enclosure and spent nearly an hour on the loose.

Security staff were on hand ready to shoot the Sumatran orangutan with tranquiliser guns as a last resort.

Karta is now confined to her night pen as zookeepers work to make her enclosure more secure by installing more electric fences and cutting back vegetation. According to Adelaide Zoo’s web site, Karta is “very headstrong and smart and zoo’s most challenging orangutan to manage”.

“I think she knows she’s not done something the keepers like,” the zoo’s director of conservation programs Kevin Evans said. “She looks a little sorry for herself.”

Adelaide Zoo curator Peter Whitefield said the ape, which news reports said has the intelligence of a five-year-old, had displayed no intention to harm anyone.

“She’s always been a bit mischievous. She likes being a bit inquisitive,” he said. “Their nature is they will work on things and she just enjoys building things, unfortunately on the wrong day and in the wrong area.”