Over 10,000 Animals at London Zoo Get Weighed

Ten thousand residents at London Zoo stepped onto hidden scales for their yearly check-up on Monday. The crowd included penguins, capybaras, squirrel monkeys, and even a Vietnamese magnolia snail. Keepers worked hard to ensure every mammal, bird, reptile, fish, and invertebrate was measured and logged. Some creatures learned to step right up, while others required coaxing or were lured with food. Devices for birds hid quietly inside doorways.

A Bolivian black-capped squirrel monkey balanced on a perch during the process. Brother and sister capybaras named Gizmo and Kiwi followed the scent of treats onto the platform. The park's Bolivian squirrels even used climbing frames disguised as weighing stations to sneak them in. Inquisitive Humboldt penguins inspected the metal boxes before being rewarded with fish, then returned to their usual playtime.

ZSL London Zoo houses more than 10,000 animals spanning over 4,000 species. The smallest residents are Partula snails, tipping the scales at less than one gram. Regular weigh-ins track health, monitor development, and spot pregnancies. Measurements feed into a global information system shared with conservationists working on endangered species.

Daniel Simmonds, animal operations manager for London Zoo, explained the necessity of these checks. 'Regular weigh-ins help zookeepers track the health of our animals – including insects like the magnolia land snails, the capybaras, and Humboldt penguins – and genuinely help us manage the care of these animals, who play a vital role in our global conservation efforts.'

The Zoological Society of London marked its 200th anniversary this year. The zoo first opened its gates in 1828.