Counting the animals at London Zoo

I really like this story, which appears in Yahoo!/Sky News today:

(Quote)
From the tallest giraffes to the tiniest spiders, London Zoo is carrying out its annual animal stock take.

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.
(End quote)

Disappearances? That's a bit of an odd thing to slip into the article. What? Do some animals just wander off out into Greater London each year, bored of the lazy life in the zoo, setting out to see the bright lights and big city, perhaps winding up earning an honest living performing in a circus somewhere? Lol! :-)