Zookeepers have deployed tricks and ruses to convince their most stubborn animals to step on to the scales.
The annual count, weigh-in and measuring of more than 19,000 creatures at London Zoo presents a major logistical challenge because of the “different personalities and temperaments” involved.
But the lure of food mostly proves effective bait, while keepers also disguise scales as patches of grass.
The checks ensure the animals are healthy and help detect pregnancies.
Penguin chicks, porcupines and lions were some of the animals who had to be weight.
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.
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.
“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.
