FINAL, Tuesday 12 September 2017: African elephants use the cover of darkness to protect themselves where they are threatened by poachers, a new study has revealed.
Research, conducted by Save The Elephants and the University of Twente in partnership with the Kenya Wildlife Service, has discovered that elephants move more at night in areas that suffer high levels of poaching.
Last year Morgan, a bull elephant on Kenya’s coast who was being tracked with a GPS collar, held the world in suspense after he moved purposefully towards one of Africa’s most war-torn nations, Somalia, moving only by night and hiding by day in thick bush.
Now a new study shows that elephants in general respond to poaching by increasing their nocturnal activity suggesting a spatial awareness of where they are in danger.
“This study implies that elephants are aware of a risk landscape, and become more nocturnal where they are threatened by poaching,” said Save The Elephants’ founder Iain Douglas-Hamilton. “When danger threatens they move at speed in the open almost entirely by night showing a marvelous adaptability.”
The investigation, led by Festus Ihwagi, Save The Elephant’s senior research scientist studying for his PhD at the University of Twente, used a simple yet effective metric where researchers were able to measure the change in elephants’ behaviour by calculating the speed by night and dividing it by the speed by day to produce a ‘night-day ratio’.
With sophisticated GPS tracking techniques, the researchers calculated the mean night-day speed ratio for collared elephants between 2002 – 2012 in the Laikipa-Samburu ecosystem in Northern Kenya, a period of transition from low to high poaching for ivory.
This area sits in the core of Save The Elephants’ long-term GPS tracking project that has seen more than 100 elephants fitted with GPS collars and their movements monitored in near real-time. The risk landscape was evaluated using data from the Monitoring of Illegal Killing of Elephants programme that is run by the Kenya Wildlife Service in partnership with local organisations including Save the Elephants.
For the Night-Day ratio study, 28 female elephants and 32 males were tracked for varying lengths of time ranging from a few months to over three years with GPS locations measuring their movements day and night.
The study focused on two different periods. During the first, 2002 to 2009, poaching levels were moderate. During the second, 2010 to 2012, northern Kenya was at the height of an ivory poaching crisis. The night-day speed ratio of elephants increased significantly with the increase in poaching levels, with females using the tactic even more strongly than males. Females, who live in closely-knit families, often have young calves with them, and are usually more risk-averse than bull elephants.
“Simultaneous elephant tracking and monitoring of causes of death presented a perfect natural opportunity for studying the behavioural response of elephants to increasing poaching levels,” said lead author Festus Ihwagi. “The escalation of poaching has become the greatest immediate threat to the survival of elephants. As most poaching occurs during the daytime, their transition to nocturnal behaviour appears to be a direct result of the prevailing poaching levels.”
The researchers say the Night-Day Ratio could provide a valuable indicator for warning when elephants are feeling threatened. With only around 40% of Africa’s elephants living in sites where mortality is regularly monitored, the metric could be used to increase the geographical range in which poaching levels are monitored and so help guide the deployment of anti-poaching resources.
Key findings from the study include:
- Elephants in areas of high-level poaching areas move more at night than by day.
- As the killing of elephants increased in Northern Kenya (2010 – 2012) so did the proportion of time that elephants spend moving by night
- Both male and female elephants responded to poaching this way, but the effect was more pronounced in females.
- This change in elephant behaviour is clearly adaptive and lowers the risk to elephants when they have to move in areas of high poaching.
The Night-Day Speed ratio study was recently published online in the journal of Ecological Indicators. The full paper will be published in January 2018.
For more information, please contact:
Head of Communications
Save The Elephants
+254 (0) 708 669 635
About Save the Elephants (www.savetheelephants.org)
Save the Elephants works to secure a future for elephants in Africa. Specializing in elephant research, STE provides scientific insights into elephant behaviour, intelligence, and long-distance movements and applies them to the challenges of elephant survival. Through our thriving education and outreach programmes, we reach out to hearts and minds, making local people the true custodians of their own rich heritage. Our human-elephant conflict mitigation projects, especially beehive fences, have reduced the number of crop-raiding incidents, and provide farmers with elephant-friendly alternative sources of income. To battle the current surge in ivory poaching, our Elephant Crisis Fund is identifying and supporting the most effective partners in Africa and in the ivory consuming nations to stop poaching, thwart traffickers and end demand for ivory.