In pictures: The great London Zoo animal count

Zookeepers welcome in the New Year with the annual animal stock take

Thousands of animals at London Zoo are being counted as zookeepers begin their annual stock-take.

The count is a compulsory requirement for the zoo to keep its licence.

The information collected is shared with zoos around the world via the International Species Information System and is used to manage worldwide breeding programmes for endangered animals.

In 2015, 17,480 animals and 756 species were counted.

Zookeepers face the mammoth task of tallying up every mammal, bird, reptile, fish and invertebrate at the zoo in Regent's Park

All creatures are counted individually, apart from ants, which are counted in colonies

The zoo counted 17,480 animals in 2015

The zoo saw an increase in its penguin population after chicks were born in 2015

'Cause for celebration'

In 2015, the zoo welcomed many new arrivals including the world's first zoo-bred Lake Oku clawed frogs.

A spokesperson for the zoo said: "The 14 tadpoles were a real cause for celebration as these totally aquatic frogs, native only to Lake Oku, in Western Cameroon, Africa, are some of the most genetically unusual creatures in the world, having developed extra chromosomes throughout their evolution."

The baby sloth was named after Edward Scissorhands because of his impressive claws

Gernot, a male Western-lowland gorilla, with 22-year-old mum Effie shortly after birth

Edward the two-toed sloth was born in July and Gernot, a male Western-lowland gorilla, was born to 22-year-old mum Effie in November.

Gernot is the second offspring of silverback Kumbuka and increases the size of the troop to six gorillas.

A lively litter of 11 African hunting dog puppies also saw the pack more than treble in size.

But zookeepers had to say goodbye to Partula snails. They were reintroduced to their native Tahiti in 2015 to save the species from extinction.

How are the animals counted?

While for some keepers the task is simple, others use imaginative tactics to account for every creature.

Tiny insects like ants are counted in colonies, but all others are recorded individually.

Aquarium keepers take photos of the tanks and use still images to avoid counting the same fish twice

At Penguin Beach, keepers wait for the birds to line up at feeding time to do their headcount

The stocktake is required as part of ZSL London Zoo's zoo license and the results are shared with zoos around the world using the International Species Information System

Last year, 756 species were counted, including this ring-tailed lemur