Has dung had its day?

"You know ... they say an elephant never forgets. What they don't tell you is, you never forget an elephant." - Bill Murray.

Making accurate estimates of elephant populations is essential for their conservation. But until now, ecologists have had to rely on counting elephant dung balls - a very time consuming and error-prone technique - or aerial census techniques, which although they are useful to estimate elephant numbers in open savannah cannot be used to spot elephants in dense forest.

Now, seismic sensors developed to track enemy troop movements during the Vietnam war are being used to help ecologists monitor and conserve elephant populations.

Dr. Jason Wood and colleagues from Stanford University recorded the vibrations from the footfalls of elephants and other large mammals, including giraffes, lions and humans, using a geophone buried near a path leading to a watering hole in Namibia's Etosha National Park.

Because of the differences in the size and frequency of animals' footfalls, the researchers could tell with 82% accuracy when elephants were passing the geophone and estimate the number of elephants passing the sensor.

This is the first time geophones have been used successfully to detect and estimate elephant numbers.

Another team tried to use a US Army surplus miniature seismic system to detect crop raiding Asian elephants in Sri Lanka, but the work was abandoned after the elephants began digging up the geophones and destroying them.

So is this sayonara for the elephant dung ball - has its usefulness been superseded by this high-technology seismic alternative? Perhaps when it comes to making estimates of elephant numbers, it has. But when it comes to observing the elephants in their natural habitat, that's a different story.

As viewers of the BBC wildlife special 'Elephants, Spy in the Herd', might remember, dung can still come in handy. In that television program, renowned film producer John Downer built a totally mobile replica of a pile of elephant dung and fitted it with a camera to allow him to spy on the antics of a herd of African elephants.

Working alongside even smaller dung-covered cameras called ''plopcams', the film production team were able to get up front and personal with the elephants. The excremental cameras were even able to capture magic moments such as the herd helping a newborn baby.

But, like their seismic colleagues, it wasn't all smooth sailing for the film's production team. There were times when the elephants got a little too interested in the cameras themselves - especially as each one was coated with real elephant dung. With the cameras rolling, the elephants kicked them like footballs and even picked them up and filmed themselves.

Clearly, it seems patently obvious from these two examples that elephants aren't particularly fond of technology. And when possible, they'll sniff it out and destroy it. It's clear that the beasts simply have no wish to embrace the sort of high-technology that could potentially make their lives a lot easier. But then, I know a lot of companies like that too.

Dave Wilson