Weigh-in for London Zoo's 19,000 animals

The audit requires big scales, a long measuring tape and a lot of patience

More than 19,000 animals at ZSL London Zoo have had their vital statistics taken for the annual weigh-in.

Penguin chicks, squirrel monkeys, gorillas and tigers were just some of the creatures that had their measurements recorded.

The information shared with zoos means zoologists can compare information about endangered species.

Keepers have been using various tactics to entice the animals to stand up and take part, the zoo said.

Squirrel Monkeys investigate a set of scales during the annual weigh-in

Zoological manager, Mark Habben said: "We have to know the vital statistics of every animal at the Zoo - however big or small.

"It helps us to ensure that every animal we look after is healthy, eating well, and growing at the rate it should.

"Weight is a particularly important indicator of health, and we can even detect pregnancies through a growing waist line."

Zoo keepers hang breakfast from up high to encourage the giraffes to reach up to their full height

The zoo carries out the weigh-in so it can check up on the general health of the animals

Meerkats inspect the scales during the annual weigh-in

A Zoo keeper prepares to weigh a Giant African Land Snail