All creatures great and small are being counted by keepers at London Zoo as part of its annual stocktake.
The mammoth task will see more than 750 species accounted for over the course of a week at the tourist hotspot - including mammals, birds, reptiles, fish and invertebrates.
Inventive methods are being employed by the keepers to ensure no animal is counted more than once, including photographing the vast aquariums rather than individually tracking the fish.
The zoo said its census would also cover a string of new arrivals from 2016, ranging from Sumatran tiger cubs to Humboldt penguin chicks.
A large chalkboard was placed in the enclosure with the cubs, bearing each tiger's name and a tick next to them. It received a playful gnawing from one of the curious occupants.
Required as part of ZSL London Zoo's licence, the annual event includes every animal, with all other British zoos required to do similar yearly counts.
Tiny creatures such as ants and locusts are counted in colonies, but all others are recorded individually.
Last year, a silverback gorilla's daring escape from an enclosure sparked a lockdown at the zoo and shot it into the headlines.
Kumbuka exited his enclosure through two unlocked security doors and guzzled five litres of undiluted sugar-free squash before he was tranquillised and moved back to safety.