One More Hurdle for Asian Elephants: Climate Change
Wild elephants populations in Myanmar are considered endangered and are facing decline due to a number of factors. From being captured, to being poached for ivory and meat, to losing habitat as a result of deforestation, elephants are constantly fighting for survival. And now according to new research, elephants have one more thing to be concerned about: climate change.
Hannah Mumby from the University of Sheffield, who led the study, says: "If the climate changes by even a few degrees it can substantially reduce survival [of the Asian elephants]." The study shows that climate may have a greater impact on elephant populations than previously thought.
In the study, researchers investigated the effects of monthly climatic variation on survival and causes of death in Asian elephants using nearly forty years of data for over 1000 elephants monitored at four sites in Myanmar.
Temperature had a significant effect on survival in both sexes and across all ages. For young elephants between 1 month and 17 years, maximal survival was reached at around 24oC (75oF), whereas newborns and mature elephants had maximal survival at even lower temperatures. Departures from this temperature increased mortality.
Because elephants spend more time during the year in temperatures higher than 24oC, it makes sense that more deaths would occur during hotter periods. However, the causes of death during these higher temperature periods were mainly due to infectious disease and heat stroke, while colder month lead to death from non-infectious diseases and poor health in general. Climate change will exacerbate mortality rates as it may lead to faster spreading infectious diseases, increased drought, and limited access to freshwater supplies, which will affect elephant survival. The research also found that survival was also related to rainfall, with elephant populations thriving during the wettest months.
With trends leaning towards higher global temperatures, along with higher variation in temperature between seasons, climate change may pose a challenge to the survival of species such as Asian elephants.
The Myanmar region is predicted to experience a rise of 0.1 to 3oC, over the next 30 to 40 years and it is also expected that there will be fewer monsoon months. These two changes may appear nominal, but as the research suggests, these slight changes in climate do not appear promising for the Asian elephant populations.
Read more about the topic and Mumby's research at the lNatural Environment Research Council.
Elephant image via Shutterstock.