Annual Weight-in at the London Zoo

Once a year every year, all the crew of the London Zoo is on the deck for the annual weigh-in of the 19,000 animals residents of the ZSL London Zoo.

From tiny frogs to Lions, Giraffes and Elephants, all animals need to be weighted in order to monitor their well-being.

This exercise requires all sorts of scales and balances adapted to each animal size. Zoo keepers have to be creative in order to get the creatures let them take their measurements.

The data collected is then shared with other zoos in a global database that provides key information for nature conservationists in programs designed to preserve endangered species.

Weighting a tiny frog with a spoon balance.

A waxy tree frog sitting on a spoon. Credit:


As you can see, some animals need to be lured with treats in order to get them on the balance scale.

treating animals to get them on the scale balance.

Tammy, our tree anteater, gets some tasty treats during her weigh-in.

Big animals, big scale challenge. how a zoo is weighting a camel is quite impressive, as you can see in the following photo:

Camel Weight-in

Our keepers look happy with our camel’s weigh-in result.








The great Animal Weigh-In happens once a year during the summer holiday.

Source: Weight-in at London Zoo