Packing a Trunk
danger posed by poachers. A study published in the peer-reviewed Ecological Indicators journal in September suggests that elephants are too, and they’ve begun moving at night, taking advantage of darkness to avoid them.
The research, carried out by the Kenya-based charity Save the Elephants and the University of Twente in partnership with the Kenya Wildlife Service, used GPS tracking and mortality data collected in northern Kenya between 2002 and 2012. The data helped calculate a “night-day speed ratio”—the amount of time spent moving during each of these periods—of elephants in relation to levels of poaching in the nearby areas. When poaching threats were greatest, both male and female elephants traveled and ate more at night than during the day. These activities make them visible to hunters; under the cover of night, that threat is greatly reduced.
Although the adaptation could be saving their lives, Save the Elephants founder Iain Douglas-hamilton says, “This alteration in movement behavior has implications for their foraging strategy, reproduction and survival, which are not yet fully understood.” Although elephants can see in dim light, baby elephants may lose their mothers in darkness. And searching for food at night could also leave elephants vulnerable to attacks by lions and other predators that hunt in the dark. Elephants’ lack of movement at night normally keeps them hidden from these natural threats.
These findings confirm and expand on previous research on elephant behavior, such as a study published in March finding that African elephants in the wild sleep much less than elephants in captivity and spend much of their time fleeing poachers when that danger is present.
Ian Redmond, a consultant who focuses on elephants for the British animal rights organization Born Free Foundation, calls the use of GPS monitoring in this study “a stroke of genius.” Tracking when elephants move with this technology could provide clues about poaching levels on a regular basis. That information can be used to alert anti-poaching patrols in time to stop killings: When the GPS indicates nighttime movement, researchers will know that poachers are in the area. “It truly has potential to save elephants’ lives,” Redmond says.