By Daniel Cressey
Poaching by its very nature happens out of sight and out of hearing of most people. But in the forests of Africa, someone is listening.
Last week, audio from the Elephant Listening Project was released, featuring the actual moment an elephant was killed by poachers (see video). The low-frequency recording, which sounds almost abstract, was captured by some of the special microphones set up by the project in the forests of Gabon and the Republic of Congo. The aim is to monitor the sounds that forest elephants use to communicate, which humans can sometimes feel but barely hear.
Nature interviewed behavioural ecologist Peter Wrege of the The Cornell Lab of Ornithology at Cornell University in Ithaca, New York, who directs the project, which is largely funded by the US Fish and Wildlife Service programme ‘Wildlife Without Borders’.
How does the listening project help elephant conservation? For a species that uses acoustic communication, it is possible to monitor aspects of its ecology and behaviour by placing efficient recorders in multiple, remote locations where they can record for long periods of time without human presence influencing the animal's behaviour.
For example, other than counting dung piles along a transect to try to estimate population density, the only typical method of collecting data on forest elephants is by direct observation at clearings in the forest, measuring things like sex ratio, visitation frequency and reproduction. Although some of these measurements can't be made just from acoustic records — at least not yet — relative numbers of elephants and reproductive activity can be measured, and not just at clearings but anywhere.
And can it help to stop poaching? In the area of [stopping\ illegal hunting and poaching, we have made some important contributions. Acoustic methods allow us to directly measure the hunting pressure in a protected area because we are recording actual gunshots. We helped to expose, for example, that there was a lot more illegal hunting going on in Loango National Park in Gabon than had been thought, and this has given impetus to fielding an anti-poaching team in the most-at-risk parts of this protected area. More....