10 adorable photos from London Zoo's annual weigh-in show curious monkeys, penguins, and meerkats stepping on the scale

• London Zoo weighs and measures every single one of its animals each year.
• Zookeepers use the data to monitor animals' health and well-being.

Every year, animals at London Zoo step on the scale for their annual weigh-in — and, with 14,000 animals to measure, it's a task that takes zookeepers several days.

They use the information to monitor the animals' health and well-being, entering their findings into a database shared with zoos worldwide to compare and track data about endangered species, according to the zoo's official website.

Here are 10 adorable photos from this year's weigh-in from August 24.

At the London Zoo's annual weigh-in on August 24, Humboldt penguins lined up at the scale.

Humboldt penguins line up to be weighed during London Zoo's annual weigh-in on August 24, 2023.      Kirsty Wigglesworth/AP

Some penguins had to be picked up and placed in the right spot by a zookeeper.

Penguins are weighed at London Zoo.      Wiktor Szymanowicz/Future Publishing via Getty Images

A Sumatran tiger tried to climb the large ruler in its enclosure.

A Sumatran tiger during the annual weigh-in at London Zoo in 2023.      James Manning/PA Images via Getty Images

Frank the meerkat had his turn on the scale.

Frank the Meerkat is weighed during London Zoo's annual weigh-in.      Kirsty Wigglesworth/AP

He appeared interested in checking the zookeeper's work.

Frank the Meerkat is weighed during London Zoo's annual weigh-in      Kirsty Wigglesworth/AP

An Asian small-clawed otter yawned while being measured.

An Asian small-clawed otter yawns during London Zoo's annual weigh-in.      Kirsty Wigglesworth/AP

A Western Lowland gorilla examined the ruler from a tree perch.

A Western Lowland gorilla sits next to a ruler during the annual weigh-in.      Wiktor Szymanowicz/Future Publishing via Getty Images

A zookeeper rewarded a squirrel monkey with treats for participating in the weigh-in.

A zookeeper weighs a squirrel monkey during the annual weigh-in.      Wiktor Szymanowicz/Future Publishing via Getty Images

Every animal at the zoo, no matter how small, gets a turn. A Mexican redknee tarantula was weighed in a glass bowl placed on a scale.

A zookeeper weighs Mexican redknee tarantula during the annual weigh-in at London Zoo.      Wiktor Szymanowicz/Future Publishing via Getty Images

A stick insect blended right in with the zookeeper's wooden ruler.

A member of staff measures a stick insect during the annual weigh-in at London Zoo.      James Manning/PA Images via Getty Images