The London Zoo has a unique way of documenting all 20,000 of its animals

It’s an annual rite of passage, but the weigh-in at the London Zoo is quite an undertaking.

Videos by Rare

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Every year, zookeepers at the iconic institution to gather their animals — all 20,000 of them — for height and weight checks.

Whether it’s dangling meat over lions or luring penguins to the scales with foodstuffs, the documentation process takes hours, but it helps the zoo keep tabs on its residents.

Afterwards, the zoo then shares the info with its zoological counterparts.

“By sharing information with other zoos and conservationists worldwide, we can all use this knowledge to better care for the endangered species we’re striving to protect,” said Mark Habben, the zoological manager at ZSL London Zoo.

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