COUNTING large mammals such as elephants, lions and rhinos isn't a particularly difficult task, even for the most arithmetically-challenged among us.
But spare a thought for the staff at one of the UK's premier zoos who last week began the annual count of all the animals in its care – including some rather more tiny critters.
Keepers at Colchester Zoo started their yearly 'stock take' on Thursday and expect the task to take at least a week.
The count, which takes into account births, deaths, new arrivals and other animal movements, is a legal requirement which must be fulfilled in order for the 60-acre facility to retain its zoo licence.
However, as curator Sarah Forsyth explained, the exercise has other benefits too.
"It is important as it is at this time of year that we send the data out to other zoos in the UK and throughout Europe, so that coordinators of breeding programmes for our endangered species know births, deaths or transfers over the last year and can then make informed recommendations for new breeding pairs so that captive populations can continue to thrive.
She added: "Obviously the keepers are aware of how many animals they look after on a daily basis but this gives us the opportunity to count up some of the more difficult species to keep track of such as the fish and invertebrates.
"Our biggest challenge by far will be the leaf cutter ants, as their colony consists of between 250,000 and 500,000 individuals.
"Due to their high number and the fact they give a very nasty bite, keepers won't be counting individuals but making an estimate of their total numbers."
Once the count is completed, the numbers will be uploaded to the International Species Information System, which provides accurate zoological data to more than 800 zoos, aquariums and related organisations in almost 80 countries.
The 2012 count at Colchester Zoo – which this year celebrates its 50th birthday – identified that it had 3,000 animals excluding the ant colony.
The zoo is open between 9.30am and 4.30pm (final admission 3.30pm) until March 29, 2013. Admission costs from £8.50.
For more information, call 01206 331 292 or visit www.colchester-zoo.com
