Tracking Elephant Poachers' Killing Grounds

The idea of taking on Africa’s illegal ivory trade can seem overwhelming. Poachers kill tens of thousands of elephants—and sometimes several park rangers—every year. In 2011, it’s thought that poachers killed one out of every 12 of the world’s elephants, sometimes mowing them down with automatic weapons. The resulting ivory can pass through several nations before reaching a final destination, making tracing its origins a difficult task. It gets worse: There’s evidence that organized crime is involved.

But there might be a sliver of hope: After a decade of work, biologists have honed in on a way to test DNA of seized illegal ivory shipments, to determine where the ivory originates from. After testing some of the ivory taken from large shipments every year since 1996, the team found that 86 percent or more of the ivory seized since 2007 comes from just two regions in Africa. That means governments and other organizations could make a big difference just by concentrating efforts to those regions.

Eighty-six percent or more of the ivory seized since 2007 comes from just two regions in Africa.

The work comes from a University of Washington lab led by biologist Samuel Wasser. The biologists worked with the International Criminal Police Organization to test small disks of ivory, which were sliced from near the base of the elephants’ tusks. Their research ramped up after 2013, when signers of the Convention on the International Trade in Endangered Species of Wild Fauna and Flora, an international agreement about endangered-species poaching, unanimously decided that all large shipments of illegal ivory that officials find should undergo DNA testing.

Meanwhile, lab members have also been DNA testing elephant dung and hair that they’ve found throughout Africa. The researchers plot their results on a map, which shows that elephants living in different regions vary slightly, genetically. By comparing the genetics of the ivory samples with the known genetics of elephants living in different regions, the biologists guess where a tusk’s owner once lived. In a new study, the team demonstrated that, for the majority of tusks, their method is accurate within about 270 miles, or about the width of a Midwestern state.

The next step for the biologists is improving the precision of their test, to give officials an even better idea of where illegal ivory comes from. It’s also important to make sure the test works quickly. Poachers may change their locations once officials crack down on their current killing grounds, and the DNA test has to keep up. For the elephants whose tusks Wasser and his colleagues do test, it’s already too late, but perhaps their DNA can help protect their genetic relatives from future danger.