Zookeepers with clipboards are coaxing, corralling and counting creatures as London Zoo begins an annual census of its 17,000 residents.

The zoo is home to more than 750 species, from red-kneed spiders to Sumatran tigers, and all must be accounted for. The yearly stock-taking is required under the license terms for all British zoos.

New arrivals this year include 10 young Humboldt penguins, three tiger cubs and six baby Philippine crocodiles — the first ever bred in Britain.

The count began Monday and is expected to take about a week. Tiny creatures such as ants are counted in colonies, but all others are recorded individually.

The data is entered into an international computer database of animal collections and used to plan zoo management and breeding programs for endangered species.