For centuries the exceptional memories of elephants have been the theme of fables. Now new research from Professor George Wittemyer of Colorado State University’s Department of Fish, Wildlife and Conservation Biology and his team proves that elephants’ tremendous memories of their habitats and their resources contributes to their survival in challenging environments.
The study, “Elucidating the significance of spatial memory on movement decisions by African savannah elephants using state-space models,” published today in the Proceedings of the Royal Society-B, is the first of its kind to use advanced statistical analyses of high-resolution tracking data to investigate fundamental questions of elephant decision-making.
“It is really exciting to engage with the new windows into wildlife behavior that technology is opening,” said Wittemyer, who is also chairman of the Save the Elephants Scientific Board. “The intricate knowledge we are gaining from high-resolution tracking is driving a ‘big data’ revolution in behavioral ecology and wildlife conservation.”
Using advanced animal tracking technology, researchers analyzed the movements of elephants in Etosha National Park, Namibia. Elephants demonstrated various types of movement depending on the context of the situation. Movements to access waterholes were distinct from movements in other contexts, being rapid and directed. Using these distinct movements for waters, the team found that elephants consistently choose to access the closest water point to their location, beginning purposeful movements towards water across great distances. The greatest movement recorded was a straight-line movement to water nearly 50 kilometers away.
“We have anecdotes of incredible, singular long-distance migrations of elephants to far-flung waterholes throughout Africa,” said lead author Leo Polansky of the Department of Fish, Wildlife and Conservation Biology at CSU. “Exploring their movement behavior relative to water and their selection among the suite of comparably close waterholes presented a great opportunity to study their decision processes and how these are influenced by environmental and social factors.”
Direct travel across an arid landscape toward water is critical for minimizing travel distance and the energy the elephants expend to get there. This study is the first to show the mechanisms whereby their remarkable memory contributes to survival in the wild.
“We have recognized the detailed landscape knowledge of elephants for some time, but it is difficult to assess their spatial memory in the wild,” said Werner Kilian, an author of the study and researcher with the Etosha Ecological Institute. “The intricate understanding of their spatial context demonstrated in this study is a testament to the species’ cognitive ability.”
The study can be found at http://rspb.royalsocietypublishing.org/content/282/1805/20143042.