London Zoo has completed its annual weigh-in, meticulously measuring approximately 10,000 animals to track their health and development. The event involved a diverse range of residents, including penguins, capybaras, squirrel monkeys, and even Vietnamese magnolia snails.
Keepers employed various methods to encourage the animals onto the scales. Some, like the capybaras Gizmo and Kiwi, were enticed with food. Others, such as the Humboldt penguins, were lured with the promise of fish before returning to their enclosures. For smaller creatures like the Partula snails, which weigh less than a gram, specialized devices were used. The zoo's Bolivian black-capped squirrel monkeys were weighed on perches, while others were coaxed onto scales disguised as climbing frames.
This yearly assessment is crucial for monitoring the well-being of the zoo's inhabitants, which comprise over 4,000 species. The data collected is entered into an information system shared with conservationists worldwide, providing vital statistics on endangered species.
"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," said Daniel Simmonds, London Zoo's animal operations manager.
The Zoological Society of London, which operates the zoo, has a long history, having celebrated its 200th anniversary in 2026. The zoo itself first opened its doors in 1828.