Calling All Critters: Stand up and Be Counted It's counting day at the London Zoo, and no one is exempt - not even tarantulas. Each year the London Zoo has to take a detailed census of every living thing in its care to comply with its license terms. A keeper counts penguins at London Zoo in London, Wednesday, Jan. 4, 2012. The annual count took place at the zoo Wednesday as keepers individually counted every animal and species at the zoo. The compulsory count is required as part of London Zoo's license. (AP Photo/Kirsty Wigglesworth) Close That means workers armed with clipboards and plenty of patience had to count every animal Wednesday. It's not easy when there are more than 18,000 animals at the site, and every one has to be accounted for. Zoo manager Mark Habben says the count is a challenging task because many of the animals are very fast moving and are adept at hiding in their enclosures.