Today the illegal wildlife trade is the world’s fourth largest form of internationally organized crime and African elephant ivory is a major part of that trade. Roughly 50 000 African elephants are now being killed each year from a population of fewer than 500 000 animals. Poaching is driving these iconic animals toward extinction.
In recent years colleagues have used DNA evidence to trace the origin of illegal ivory and thereby helping police. Knowing the primary areas where elephants are poached could help combat ivory trafficking at its source.
In the past DNA from elephant dung, tissue and hair collected across the African continent was used to map genetic signatures for regional populations. A new study by researchers of the University of Washington and Interpol uses different methods to extract DNA from ivory, allowing them to analyze seized contraband and determine the elephant's original population.
Africa is a huge continent, and poaching is occurring everywhere. When you look at it that way it seems like a daunting task to tackle this problem. But when you look at large ivory seizures, which represent 70 percent of illegal ivory by weight, you get a different picture.
The group used their method to analyze 28 large ivory seizures, each more than half a ton, made between 1996 and 2014. The samples include 61 percent of all large seizures made worldwide between 2012 and 2014.
The colleagues assigned the geographic origin of ivory seizures by statistically matching genotypes from savanna or forest elephants to a geographic-specific allele frequency map of 16 microsatellite DNA loci. All but one of the 28 seizures were concentrated in only four areas. Most seizures made since 2006 were concentrated in just two areas.
The investigations also show a shift in poaching hotspots beginning in 2006. During the earlier years, 1996-2005, most forest elephant ivory analyzed was assigned to the eastern Democratic Republic of Congo, but none of the forest elephant samples after 2005 came from that area. Two seizures of savanna elephant ivory, in 2002 and 2007, came from Zambia, but the country was not represented in any of the samples after 2007.
Recent efforts to curb trafficking have focused on curbing demand, but those seem painfully slow.
When you're losing a tenth of the population a year, you have to do something more urgent -- nail down where the major killing is happening and stop it at the source. Hopefully our results will force the primary source countries to accept more responsibility for their part in this illegal trade, encourage the international community to work closely with these countries to contain the poaching, and these actions will choke the criminal networks that enable this transnational organized crime to operate.