The London Zoo has a special tradition that happens this time each year: the keepers make a complete inventory of every animal they own.
That doesn't sound too bad, until you find out that the zoo has more than 20,000 animals in its two locations.
Luckily, the zoo's staff gets some help every year from the animals they look after. This is an important job after all. It may not mean much if one of the penguin's doesn't get counted, but everyone feels safer knowing all of the lions and tigers are accounted for.
Information on the more than 700 species of animals in the zoo are sent to an international database, helping zoos around the world keep track of animal populations.
Check out some of the great photos from this year's counting spree:
This board was cute, but it didn't stay up for very long.
These two young tigers, Achilles and Karis, were born during the Summer, so this was their first time being counted.
"Don't forget about me!"
Malcolm, the Aye Aye baby, was another new addition this year.
And because we know you don't want this list to end, here are some more photos from past years' stocktakings:
It's a good thing Kumbuka is safe and accounted for, last year he made international headlines when he escaped from his enclosure.