It reminds me of another ZSL article that said that London Zoo's female gorillas were looking forward to the arrival of a new male gorilla from France. Were they doing Linguaphone courses? No, they didn't know he was coming.
They went over the top that time. Gave them photos of the male and put(I think) jam or something on them so they were 'looking' at the picture when the publicity photos were taken. That was the ill-fated 'Yeboah' of course.