Animals at London zoo get their annual weigh-in

By Gege Li

Photographer Brett Cove/ZSL

THESE charming residents of London Zoo, run by the Zoological Society of London, are just a few of the 20,000 animals that are being weighed and measured as part of its annual weigh-in.

Recording heights and weights helps zookeepers keep tabs on each animal’s health and well-being, such as whether they are growing at the appropriate rate, as well as to monitor or detect pregnancies.

However, since it isn’t always easy getting the animals to remain in one place to be measured, tactics often need to be deployed to get them to stand or stay still.

One way to do this is through play. The image above shows Arya, an Asiatic lioness who arrived at the zoo in April, stretching out against a giant ruler after being enticed with a ball.

In the image above, these Bolivian black-capped squirrel monkeys have been encouraged to climb onto the scales with treats.

Above, huge callipers are needed to measure Polly the Galapagos tortoise’s shell, while at the other end of the scale, the weigh-in for a midwife toad (below) requires only a spoon-sized instrument.