Census day for British zoos

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Kumbuka, a Western Lowland gorilla, in his enclosure during ZSL London Zoo's annual stocktake of animals, in London, England, Jan. 2, 2014.

The zoo's annual stocktake requires keepers to check on the numbers of every one of the 800 different animals species held, including every invertebrate, bird, fish, mammal, reptile, and amphibian.

Bell's Anglehead lizard

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Zookeeper Ben Baker looks at a Bell's Anglehead Lizard as it sits on the end of his pencil during the annual stocktake at Chester Zoo in Chester, northern England, Jan. 2, 2014.

The annual stocktake is a compulsory count, with the results data shared with zoos around the world and used to manage the international breeding programmes for endangered animals.

Penguins

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A zookeeper records the number of penguins during at the London Zoo, Jan. 2, 2014.

Ringtailed lemurs

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Ringtailed lemurs look at a clipboard being held by zookeeper Mark Wylie at Chester Zoo in Chester, northern England, Jan. 2, 2014.

Jungle Nymph stick insect

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A zookeeper records a Jungle Nymph stick insect at the London Zoo, Jan. 2, 2014.

Penguins

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Zookeepers record the number of penguins at the London Zoo, Jan. 2, 2014.

Meerkats

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A zoo worker counts meerkats at the London Zoo, Jan. 2, 2014.

Penguin

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Penguins are seen during the London Zoo's annual stocktake of animals, Jan. 2, 2014.

Eagle owl

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Keeper Jamie Pearce inspects eagle owl Max in his enclosure at the London Zoo, Jan. 2, 2014.

Penguin

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A penguin looks at a zookeeper's clipboard during a stocktake at the London Zoo, Jan. 2, 2014.

Tawny owl

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A zookeeper holds Alberta, a tawny owl, during the London Zoo's annual stocktake of animals, Jan. 2, 2014.

Eagle owl

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A keeper holds Max, an eagle owl, at the London Zoo, Jan. 2, 2014.

Meerkats

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The number of meerkats is recorded during the London Zoo's annual stocktake of animals, Jan. 2, 2014.

Meerkats

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A zookeeper records the number of meerkats during at the London Zoo, Jan. 2, 2014.

Spectacled owl

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A keeper holds Elton, a spectacled owl, at the London Zoo, Jan. 2, 2014.

Pelicans

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Pelicans are counted at the London Zoo, Jan. 2, 2014.