All penguins use sounds to communicate. Chicks in large colonies need to be
able to attract their own parents so that they can be fed, adults need to recognise one
another when they come back from fishing trips, etc. Different species make different
noises. African, Humboldt, Magellanic and Galapagos all make braying sounds (like a
donkey) and each of these species has at some time been known as "Jackass"
penguins as a result. Their chicks, in contrast, make a high pitched whistling noise to
demand feeding. The Yellow-eyed penguin makes a trilling sound (not unlike the old
"trim-phone").
