In pictures: London Zoo's animal census

Twelve Humboldt penguins are among the animals undergoing their first experience of London Zoo's annual stocktake

Twelve Humboldt penguin chicks are among the new entries in the list of residents at London Zoo, which is conducting its annual census.

Each year, keepers take a record of all the animals at the zoo, which houses more than 700 different species.

The count of every mammal, bird, reptile, fish and invertebrate usually takes about a week to complete.

The animal stocktake comes a year after a fire ripped through the zoo, killing an aardvark and four meerkats.

Although a full count - required as part of the zoo's licence conditions - is undertaken once a year, keepers have an inventory which is updated continuously.

Animal operations manager Angela Ryan said: "It always makes for a busy start to the year.

"Our keepers all have their own ways of tallying up the animals in their care - from taking pictures of the tanks in the aquarium to avoiding counting the same fish twice, to using training and rewards to count larger groups such as our squirrel monkeys and Humboldt penguins."

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