COPENHAGEN, Jan 27 (AFP) - Monkeys at Copenhagen Zoo are going ape over organic bananas and other fruits, rejecting traditional foods left in their cages, zookeepers said Monday.

"For one reason or another, the tapirs and chimpanzees are choosing organically grown bananas over the others," keeper Niels Melchiorsen told the magazine Oekologisk Jordbrug (Ecological Agriculture).

"Maybe they are able to instinctively tell the difference, and their choice is not at all random," he suggested.

"The chimpanzees are able to tell the difference between the organic and the regular fruit," Melchiorsen reported: "If we give them organic and traditional bananas, they systematically choose the organic bananas, which they eat with the skin on."

"But they peel the traditional bananas before eating them," he added.

Copenhagen Zoo, which hopes to be awarded a "green label" as an environmental zoo, began last year feeding its animals at least 10 percent organic products.