27 August 2020

Penguins, squirrel monkeys and camels are just some of the creatures who had their vital statistics recorded at ZSL London Zoo’s 2020 annual weigh-in today (Thursday 27 August).  

Four-month-old otter pups Bubble and Squeak also took to the scales for the first time alongside parents Pip and Matilda, while heavily pregnant okapi Oni - due this autumn - tipped the scales at 288kg, understandably a few kilos heavier than her pre-pregnancy weight of 250kg.   

Tasty treats encourage animals

Galapagos tortoise Dolly slowly made her way to the weigh-in by following a trail of traffic cones to the grass covered scales in her outdoor enclosure, while patient keepers encouraged the Zoo’s troop of ring-tailed lemurs onto the scales one by one by offering up a few tasty treats.  

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.  

Oni the pregnant okapi has her stomach measured by keepers Megan Harber and Jessica Young showing a pregnancy increase of 14cm at London Zoo

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.  

From the tallest giraffe to the tiniest ant  

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 and monitor pregnancies, which is so important as many of the species at ZSL London Zoo are endangered and part of international breeding programmes, such as Oni the okapi who is currently 14 months pregnant with her second calf.  
“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.” 

Galapagos tortoise Polly is weighed by keepers Joe Capon and Charli Ellis 116.7kg at ZSL London Zoo

With different personalities and temperaments to take into account, zookeepers used ingenious tactics to entice the animals to stand up and be measured; ’tricking’ penguins into walking over scales as they lined up for their morning feed and encouraging squirrel monkeys onto the scales through fun training activities.  
ZSL London Zoo reopened to the public on Monday 15 June after an unprecedented three months of closure due to the coronavirus lockdown. The loss of income put the charity zoo under huge financial pressure as they continued to provide the highest level of care for their animals.

Now open to limited numbers only, ZSL, the international conservation charity behind the Zoo, is calling on the public to help ensure they stay open by booking a ticket, joining as a member or donating to ZSL.    

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