Bullfrogs, pythons, and penguins were among creatures being coaxed onto scales at London Zoo this week for the annual check on their weight and size.
The check-up allows keepers to assess the animals’ general health, find out about pregnancies, when they are about to molt, and help to administer medicines according to their weight.
The information is shared with zoos around the world by ZSL, a charity devoted to the worldwide conservation of animals and their habitats.
But actually getting the animals to stand up and be measured is no easy task, involving, for example, tricking penguins into walking over scales as they line up for their morning feed or hanging breakfast up high to encourage lions to reach up to their full height.
The annual weigh-in of animals, also including Asiatic lions, South African porcupines, and South American coatis, will take a week to complete.