A DEVICE used to track enemy troop movements during the Vietnam war may give conservationists a better understanding of elephant behaviour.
Forest elephants, thought to be a different species from their kin on Africa’s savannahs, have been difficult to count because dense tree cover hides them from aerial surveys. Until now, the best estimates have come from counting dung balls, but this is labour-intensive and error-prone.
Jason Wood and his colleagues at Stanford University in California instead tried using a small seismic detector, or geophone, to track the rumble of elephant footfalls. The researchers buried a geophone near a waterhole…
