2:49am UK, Tuesday January 05, 2010
Laura Bundock, Sky News Online
From the tallest giraffes to the tiniest spiders, London Zoo is carrying out its annual animal stock take.
Zookeepers there will spend the day counting every creature.
Which is easy if you're in charge of the slow-moving sloths, but slightly trickier if you're Rachel Jones, the aquarium manager.
With 5,500 fish to count, it can get confusing.
"There are some that spend their lives living in the rock and occasionally you'll see a little face poking out, and you have to be quick to count it," she said.
"Others bomb all over the place and are really hard to catch up with."
It's not just the fish which are counted. Every coral, snail and starfish is also added up.
London Zoo is home to 752 species and, with several new exhibits, this year's stock take will be the zoo's biggest ever.
Last year, they counted 15,107 animals. This time around, there are giant Galapagos tortoises, aardvarks, a new Komodo dragon and newborn lion cubs to include.
And with births, deaths and even disappearances each year, the annual roll call is vital for keeping tabs on the zoo's inhabitants.
"On the whole we've got a good idea of how many animals there are, especially if they change tanks or we move them, but the count does give us a clear picture of exactly who's where," added Rachel.