22 August 2019

Penguin chicks, porcupines and lions are just some of the creatures who had their vital statistics recorded for the start of ZSL London Zoo’s 2019 epic annual weigh-in today (Thursday 22 August).

Meerkat Dracula, the heaviest of the Zoo’s mob, weighed in at 1kg, while Oni the okapi - an Endangered species from Central Africa - tipped the scales at 247kg.

With more than 19,000 animals in their care, ZSL London Zoo’s keepers spend hours throughout the year recording the heights and weights of all the animals - information which helps them to monitor their health and wellbeing.

Annual weigh in helps zookeepers across the world

The annual weigh-in is an opportunity for keepers at ZSL London Zoo to make sure the information they’ve recorded is up-to-date and accurate, as each measurement is then added to the Zoological Information Management System (ZIMS), a database shared with zoos all over the world that helps zookeepers to compare important information on thousands of endangered species. 

Ring-tailed coati Brush steps onto the scales

ZSL’s assistant curator of mammals, Teague Stubbington, says: “We have to know the vital statistics of every animal at the Zoo – from the tallest giraffe to the tiniest ant.

“It helps to ensure that every animal we look after is healthy, eating well, and growing at the rate they should - weight is a particularly important indicator of health and wellbeing.

“A growing waistline can also help us to detect pregnancies, which is so important as many of the species at ZSL London Zoo are endangered and part of international breeding programmes. 

Polly the porcupine is weighed by a Zookeeper at London Zoo

“By sharing information with other zoos and conservationists worldwide, we can all use this knowledge to better care for the species we’re striving to protect.”

With different personalities and temperaments to take into account, zookeepers had to use ingenious tactics to entice the animals to stand up and be measured; ’tricking’ penguins into walking over scales as they line up for their morning feed and hanging breakfast from up high to encourage the lions to reach up to their full height. 

Oni the okapi steps onto the scales at London Zoo

Visitors to ZSL London Zoo can ‘weigh in’ on the action themselves this bank holiday weekend – by guessing the combined weight of the Zoo’s Humboldt penguins Heathcliff and Lily. Plan your trip today to be in with a chance to win an overnight stay at the fabulous London Zoo Lodges.

Our August bank holiday 2019 competition has now ended. Thank you for getting involved.


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