The penguins are my favorite exhibit at the San Francisco Zoo. SF has a maritime climate that seems fairly similar to London. A keeper hand-feeds them fish on a regular schedule, with vitamin-supplemented fish for particular penguins that need supplements. They thrive on the fish - but they need a lot of fish. Each penguin gets 2 or 3 six-inch fish a day.
About 15 minutes before feeding time, they gather in a circle and start chanting - almost seems like a singaround. They're very enthusiastic about eating, too.
What do the white pelicans eat in London?
-Joe-