London Zoo has begun the mammoth task of weighing and measuring all its animals as part of the annual weigh-in to check on the health from the smallest to the largest of beasts.
It's no small task, as the more playful creatures see it as a game rather than a serious zoological endeavour.
At Penguin Beach, Pickle the young Humbolt penguin posed beautifully on the scales, but his friends were rather more mischievous and took the opportunity to hop on and off the scales rather than stand still.
It's all good fun, but keeper Angela Ryan says there is a serious side.
"As keepers it’s really important because some animals, especially the ones you can't really get close to, you can't see their condition that well, for example something covered in feathers or something covered in fur, you can't always see the condition that they are in so by weighing them, we know where we are with them," she says.
Pickle weighed in at a healthy 3.5 kilograms.
It's also important for keepers to check that the captive creatures are not putting on too much weight through inactivity. Their weight also might give clues as to which ones may be pregnant.
For other animals, it's the length and height of them that count more than weight.
It’s rather tricky to measure an African millipede that won't straighten out, but one keeper managed to estimate he was 25 centimetres, three short of the longest ever recorded at 28 centimetres.
The giraffes were easily tempted to stand by a wall chart on the side of their house - the lure of fresh leaves to munch on made it easy for the keeper to record heights of between 4 and 4.5 metres.
Ms Ryan says the trickiest animals to weigh are the meerkats.
"You've got lots of them at once and you've got to get them there one at a time and they all want to be there at the same time. We try and keep it positive so they've got a little reward for coming on there which makes it a really exciting place to be, so you've just got to make sure you've got them queuing up, so to speak," she says.
But by far the easiest animal to weigh was Dirk, the 72-year-old giant tortoise. He just stood calmly as he was weighed and measured.
He came in at a whopping 170 kilograms, with a 51 inch shell and 34 inch height.
All the data collected by the zoo is shared with other zoos and breeding programmes around the world so they can better understand the life-cycles of all the animals.
Reuters