The tricky business of weighing London Zoo's animals - in pictures

Bullfrogs, pythons and penguins were among creatures being coaxed onto the scales for the annual check on their weight and size

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  Zookeeper Martin Franklin encourages Humbolt penguins onto scales during the annual weigh-in at London Zoo, London, Britain. Reuters

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  A coati gets weighed at the London Zoo in London, Britain. EPA

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  Meerkats are weighed on a scale during a photocall at London Zoo. AFP

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  Asiatic lionness Heidi stands next to a measuring scale during a photocall at London Zoo. AFP

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  An African bullfrog sits on scales during the annual weigh-in at London Zoo, London, Britain. Reuters

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  Zookeeper Unnar Aevarsson takes readings of an African bullfrog during the annual weigh-in at London Zoo, London, Britain. Reuters

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  Asiatic lionness Heidi stands next to a measuring scale during a photocall at London Zoo. AFP

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  A Porcupine, a large rodent is weighed during the Zoo's annual weigh-in, in London. AP

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  An Asiatic lion lies next to a measuring scale during a photocall at London Zoo. AFP

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  A young Black-headed python is weighed and recorded during the Zoo's annual weigh-in, in London. AP

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  A Meerkat investigates a clip board during the Zoo's annual weigh-in, in London. AP

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  Humboldt penguins swim under water during the Zoo's annual weigh-in, in London. AP

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  An Asiatic lioness stands in front of a measure rule during the Zoo's annual weigh-in, in London. AP

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  A zookeeper returns a giraffe to its house at London Zoo, London, Britain. Reuters

- Bullfrogs, pythons and penguins were among creatures being coaxed onto the scales at London Zoo this week for the annual check on their weight and size.

The check-up allows keepers to assess the animals' general health, find out about pregnancies, when they are about to moult, and help to administer medicines according to their weight, the Zoological Society of London (ZSL) said.

The information is shared with zoos around the world by ZSL, a charity devoted to the worldwide conservation of animals and their habitats.

But actually getting animals to stand up and be measured is no easy task, involving for example tricking penguins into walking over scales as they line up for their morning feed or hanging breakfast from up high to encourage lions to reach up to their full height.

"We have to know the vital statistics of every animal at the zoo, from the tallest giraffe to the tiniest ant," said ZSL’s assistant curator of mammals, Teague Stubbington.

"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."

Not all the 19,000-plus animals across more than 560 species at London Zoo will be weighed: sometimes just one in a colony or group will be measured.

The annual weigh-in of animals, also including Asiatic lions, South African porcupines and South American coatis, will take a week to complete.

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