Cute lion cubs and penguin chicks were among the 10,000 animals put on the scales at London Zoo’s annual weigh-in.

Rare creatures are carefully monitored as part of a global programme to protect endangered species around the world.

But zookeepers often have to use “clever tactics” to entice their animals onto the scales, like buckets of fish for the penguins, because of their individual personalities and temperaments.

This year three Asiatic lion cubs, born at the zoo in March, joined the weigh-in for the first time.

The cubs, brothers Mali and Syanii and sister Shanti, are being monitored regularly to check their growth and development. They weigh an average 17kg.  

Keeper Jessica Ray weighs Humboldt penguin Swiftie Keeper Jessica Ray weighs Humboldt penguin Swiftie (Image: Dominic Lipinski) Also being weighed were 10 rare Humboldt penguin chicks, born in the spring at the zoo.

The chicks didn’t need much encouragement to be weighed, waddling onto the scales for their breakfast — a bucket of fish!

Penguin keeper Jessica Ray noted each weight, ready to be added to the global zoo information database. 

Keeper Mick Tiley weighs Bactrian camel Noemie Keeper Mick Tiley weighs Bactrian camel Noemie (Image: Dominic Lipinski) Camel keeper Mick Tiley, meanwhile, was busy encouraging a rare pair of Bactrian camels, Genghis and Neomie, onto a giant weigh-board — one at a time, of course. Each clocked on at around 680kg, making them two of the zoo’s heaviest animals. 

Weighing the animals is part of the zoo’s monitoring programme to check the development of its new-borns, like the two lowland gorilla babies delivered at the zoo this year. Juno was born to mum Mjukuu and Venus to her mother Effie. 

“We weigh every animal from the tallest giraffe to the small tree frogs,” London Zoo’s operations chief Angela Ryan revealed. “This makes sure that they are healthy, eating properly and developing at the appropriate rate.

“Weighing for some species is the only way to detect and track a pregnancy, which is especially crucial for many endangered animals at London Zoo that are involved in global conservation breeding efforts.” 

The annual weigh-in is a chance for keepers to make sure the information is up-to-date and accurate. Each measurement is added to the Zoological Information database shared with zoos across the globe to help protect threatened, endangered and critically-endangered species and their habitats.