The problem was that the female Humboldt penguins have proven too shy in their advances, the director of the zoo in the northern port city of Bremerhaven said.

• 这家动物园位于德国北部城市不来梅港，动物园主管海克·许克说，问题是雌性洪堡企鹅向来很害羞，不会主动接近雄性。