Animals hopped, skipped and jumped on to the scales one-by-one at London Zoo for their annual weigh-in to make sure they’re fit and healthy.

Penguins, tigers, gorillas and meerkats were among the creatures queuing to be weighed.  

The keepers took stock of height and weight of 14,000 animals for a database shared with zoos around the world that compares information on thousands of threatened species.  

“We record every animal from the tallest giraffe to the tiniest tadpole,” London Zoo’s Angela Ryan explained. “This helps make sure every animal is healthy, eating well and growing at the rate it should.” 

A growing waistline can help detect pregnancies, for example, which is critical for species are threatened in the wild and is part of international conservation breeding programmes.

But keepers have to use clever tactics to get the animals to stand up and be measured. They tricked Humboldt penguin chicks into stepping over scales as they lined up for their morning feed and used tasty treats to entice Bolivian black-capped squirrel monkeys onto the scales.  

Making their annual weigh-in debut this year was Western lowland gorilla Kiburi which arrived as part of a global breeding programme for endangered species last November and critically-endangered Sumatran tiger cubs Zac and Crispin who recently had their first birthday.