As human-elephant conflict continues to rise across Africa, researchers are searching for new ways to keep a watchful eye on wild African elephants – even looking to space technologies for guidance.
In the rural community of Sagalla in Tsavo Kenya, a hotspot for crop-raiding elephants, researchers at Save the Elephants and the Department of Biology at the University of Oxford have, for the first time ever, tracked the footprints of elephants using a high-resolution handheld Garmin GPS that captures point-to-point fixes every three to five seconds, and overlaid it with free high-resolution satellite imagery to identify how plant diversity on a micro scale affects elephant movement.
In the process, the researchers have discovered that elephants make considered decisions about which paths to take based purely on their favourite food.
The findings, recently published in the journal Remote Sensing, may be critical in helping conservationists forecast potential human-elephant conflict (HEC) hotspots.
Tracking every twist and turn
The Sentinel 2A imagery, obtained through an open-source satellite managed by the European Space Agency, has enabled scientists to map every single piece of vegetation within each 10m pixel in and around Sagalla.
While elephants are normally tracked at one-hour intervals, the handheld satellite GPS captures all the twists and turns, every thorny thicket, every tree that an elephant would take on its chosen path.
The elephant data from the study covers the period from January 2015 to 2020.
Moved by the menu
The results show that bull elephants prefer to walk paths that have or lead to plants called Combretum and Cissus, which are only eaten by bulls.
Family groups will walk paths that have Commiphora and Terminalia, which are a dietary preference for family groups comprising females and young calves.
When the two groups combine and move together, they choose paths that have or lead to areas where both preferred delicacies are available, in other words ensuring there’s something for everyone.