Flamingos stand in the rain prior to being measured in their enclosure during the ZSL London Zoo’s annual weighing and measuring of their animals yesterday. Every year the keepers at ZSL London Zoo record the heights and weights of over 750 different species including lions, tigers, penguins and snakes. The heights and weights are then recorded into the International Species Information System (ISIS), where they can be shared with zoos across the world, and zoologists can compare the information of thousands of endangered species.