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Listening to Elephants

Elephant Listening Project researcher Katy Payne, in the field.
Carolyn Jensen, NPR News /
Elephant Listening Project researcher Katy Payne, in the field.
Director of Cornell's Bioacoustics Research Program, Chris Clark.
Carolyn Jensen, NPR News /
Director of Cornell's Bioacoustics Research Program, Chris Clark.

For researchers who study elephants, the basic question is: How many elephants are there?

During the 1970s and '80s — as a result of the ivory trade — Africa's total elephant population fell by more than 50 percent, from an estimated 1.3 million to 600,000. An international ban on ivory in 1989 helped some of the populations recover, but no one knows how many are left today. Perhaps as many as 300,000 elephants may live in central Africa, but the region's forests are so thick, it's hard for researchers to count them.

For National Geographic Radio Expeditions, NPR's Alex Chadwick traveled to the Central African Republic, where researchers are recording elephant gatherings at a remote clearing in order to develop a new way to monitor populations of the species.

Cornell University researcher Katy Payne believes the best way to study wildlife in dense forests is to listen for it. To test her theory and technique, she began the Elephant Listening Project. She's building an "elephant dictionary" that might help researchers learn how many elephants there are in an area, how they interact, what they're doing — and if they're reproducing.

At a clearing in the Dzanga-Sangha Dense Forest Special Reserve, her team members have deployed a series of digital recorders, powered by car batteries, that can run continuously for weeks and months. The recorders are set so they only pick up very low frequency sounds — basically elephants, wind and thunder.

Christopher Clark, director of the Biacoustics Research Program at Cornell's Lab of Ornithology, developed these "acoustic recording units", or ARUs. The recorders take in a vast amount of data that computers and researchers in the United States sort through and analyze.

The other part of the dictionary involves the work of Wildlife Conservation Society researcher Andrea Turkalo. She's lived among and studied the social behavior of Dzanga's elephants for a dozen years. Payne's idea is to join Cornell's acoustic techniques and technology with Turkalo's deep knowledge of certain forest elephants to learn what their calls mean.

But much to the researchers' alarm, those who want to resume hunting elephants for ivory may seize on the Elephant Listening Project's research as a way to demonstrate that the populations may be large and healthy enough to easily sustain a hunt.

"They hope that we can say, well, it's now easy to monitor elephants everywhere, so you might as well go ahead and hunt a few and we'll see what the trends look like," Payne explains to Alex Chadwick.

In Santiago, Chile, delegates are gathering for a conference that will consider whether to lift the ivory ban. Some 160 nations belong to CITES, the Convention on International Trade in Endangered Species. Five African nations — Botswana, Namibia, South Africa, Zambia and Zimbabwe — have put together a proposal to sell stockpiled elephant ivory, with subsequent annual quotas. Meanwhile, two other nations, Kenya and India, are calling for a tightening on the current ivory ban by moving elephants to the most protected CITES status.

Payne is in Santiago this weekend for the CITES meeting, fighting efforts to legalize the ivory trade.

"Conservation is what I care most about in this whole world," says Payne.

It's a terrible irony that people would attempt to cite her work to justify hunting elephants, Chadwick remarks during their interview.

"Right," she replies. "I'm afraid of it."

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Alex Chadwick
For more than 30 years, Alex Chadwick has been bringing the world to NPR listeners as an NPR News producer, program host and currently senior correspondent. He's reported from every continent except Antarctica.