In 2011, Kenya lost 278 elephants to poachers, compared to 177 in 2010. Today only an estimated 360 000 elephants roam the continent, compared to 700 000 in 1990.
University of Notre Dame researchers Elizabeth Archie and Patrick Chiyo studies elephants in Kenya, and particularly, the Amboseli Elephant Research Project (AERP), located just north of Mount Kilimanjaro in Kenya, which is the longest running study of wild elephants.
Archie's Notre Dame Lab combines fieldwork and genetics research to understand the causes and consequences of social behavior in wild mammals. Her research team examines how migration, mating and social patterns impact the genetics and evolution of a species and its fitness and susceptibility to diseases.
The researchers observe the animals, collect dung and other samples, which are then analysed in the lab. Their findings are revealing interesting insights into elephant population genetics and social behavior, as well as how human activities alter elephants' social and genetic structures.
Their research has found that female elephants form strong and lasting social ties with the members of their natal core group. However, male elephants move away from their core natal group at maturity and never join a new core group permanently.
Poaching interrupts the beneficial female social relationships and could lead to lower reproductive rates for females, further reducing the species. For male elephants, age is an important predictor of reproductive success. Poaching appears to reduce the age of first reproduction for males, which may increase the rate at which genetic diversity is lost from natural elephant populations.
Archie and Chiyo have also investigated the "crop raiding" behavior of African elephants. Scientists have determined that crop raiding is a male elephant preference, but that not all males participate. The Notre Dame Researchers found that up to 20 percent of males may be crop raiders, and males are twice as likely to raid at their reproductive peak.
Males older than 45 were twice as likely to raid, although some males in their 20's also participated in the raiding. The researchers discovered that younger males were more likely to raid if they were following older role models.