It is relatively easy to monitor elephant populations with flights over the open savannas of eastern, central and southern Africa, but it is much harder to do the same in the dense forests of central and western Africa. Those forests are where elephants are currently being slaughtered wholesale, said Samuel Wasser, who holds the UW's endowed chair of conservation biology and is director of the Center for Conservation Biology.
"My colleagues working in the forests are saying, 'There are no elephants left here,'" he said. "That's the problem in the forest you don't notice the change in population until it's so dramatic that it's almost too late to do anything about it."
Wasser is lead author of a paper describing the new means of determining ivory origins, being published the week of Sept. 27 in the Proceedings of the National Academy of Sciences.
The African elephant population plummeted by 60 percent from 1.3 million to just 500,000 between 1979 and 1987, largely because of ivory poachers. An international agreement banning ivory trade was enacted in 1989, but still three of the largest ivory seizures have occurred since 2002.
In June 2002, authorities in Singapore seized a shipment of about 6.5 metric tons of ivory bound for the Far East. The shipment included 532 whole tusks, many more than 6 feet long, and 41,000 small carved ivory cylinders about the size of hanko stamps, used for document signatures. The cylinders alone were worth more than $6 million.