The community of elephants that call Africa's Greater Virunga Landscape (GVL) home once thrived there. During multiple surveys of in the 1960s and 1970s, scientists found that specific locations within the GVL, like the Queen Elizabeth Protected Area and Virguna National Park, had anywhere from 1,300 to 4,000 individuals.
But starting in the 1990s, the elephants' numbers began to precipitously drop thanks to human activity like land use, political conflict and poaching. Today the African elephants throughout the continent are listed as endangered, and the highly intelligent animals seem to be aware on some level that humans are to blame for their plight. Elephants have been reported to flee from other areas where there was heavy poaching to the relative safety of the GVL, causing the population there to rise.
"There is undisputed evidence that the population in Queen Elizabeth National Park rose from 150 individuals to 2,950 in 2006 over 25 years, an increase that could not have been achieved solely by births alone," scientists reported in a recent study for the journal PLOS Sustainability and Transformation. But they note one worsening threat to the elephants' survival that they cannot run from: Climate change.
Furthermore, these effects are not felt uniformly among elephants, with older individuals suffering more than younger ones. A big factor is deforestation, which prevents the elephants from cooling down in the rising heat. But many of these areas are being destroyed by fires and commercial plantation crops such as sugar, tobacco, palm oil and cocoa.
Elephants are particularly vulnerable to the impacts of climate change because, in these heavily matriarchal societies, the older cows accumulate wisdom that they share with the youths.
"It is observed that climate change affects older elephants more than young ones in terms of survivability and migration," write study co-authors Simon Nampindo of Wildlife Conservation Society Uganda and Timothy O. Randhir of the University of Massachusetts, Amherst. "It is also likely that the undetected direct climate change impact on the elephant population is due to changes in habitats, particularly forests and wetlands used for thermal regulation."
To determine this, Nampindo and Randhir built a systems dynamic model that incorporated data on elephant populations, landscape changes throughout history and a wide variety of future climate change scenarios over the next 80 years. The data applied to elephants according to their age brackets: under 10 years old, 11 to 30, 31 to 40, 41 to 50 and more than 50 years old.
It is significant that the elderly elephants are particularly vulnerable to the impacts of climate change because, in these heavily matriarchal societies, the older cows accumulate a form of wisdom that they share with the youths. Like many animals, elephants have a form of culture and they even grieve their dead. Just as a human family suffers an irreparable loss when its elders pass away too soon, entire populations of elephants will be left leaderless and emotionally devastated as their wise matriarchs prematurely die off.
"If they are lost to changing climate, it will wreak havoc on the surviving, younger herds, as well as change the genetic profiles and structures of the herd," Nampindo said in a statement accompanying the study.
The GVL itself depends on these African elephants. Encompassing 15,700 square kilometers in Rwanda, Uganda and the Democratic Republic of the Congo and including seven national parks, three tropical high-forest reserves and three wildlife reserves (three of which are world heritage sites), the GVL includes a diverse array of animals including hippopotamuses, chimpanzees, gorillas, lions, leopards, pangolins, hogs and crocodiles. There are also thousands of plant species and hundreds of types of birds, and all of these organisms rely in various ways on the African elephants. The pachyderms' dung enriches the soil from which the plants grow; similarly, as they feed and go about their day-to-day business, the elephants knock over trees and disperse seeds.
Yet as elderly elephants struggle with the wetter and warmer conditions in the GVL caused by climate change, their fall will impact the entire African elephant population, and with it the ecosystem of the GVL. If there is any good news to be found in the recent study, it is that this calamity can be averted by the same means that it was caused — through human intervention.
"Our study results reinforce the necessity to secure and maintain wildlife corridors and restore degraded forests and savannah woodlands to guarantee elephant adaptability to climate change," the authors write. "Habitat quality and condition are critical to the survival of elephants by providing a reliable and sustainable source of food, water, and shelter for thermal regulation."
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They "show a lot of interest in the tusks of dead elephants, and they will repeatedly return to dead elephants or relatives, dead relatives, and they will come towards them."
Last year Salon spoke with Dr. Paula Kahumbu, CEO of the charitable organization Wildlife Direct and one of the world's foremost elephant experts who has spent years studying the animals in the wild. After describing how elephants have a powerful sense of smell and identify each other through odors, she added that this helps explain how they "detect the identity of an elephant that has died."
She then elaborated on how elephants grieve, describing how they "show a lot of interest in the tusks of dead elephants, and they will repeatedly return to dead elephants or relatives, dead relatives, and they will come towards them. They will touch them, feel them. If an elephant has recently died or is dying, they will even try to raise it, or they will stand around and just be with a dying elephant."
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Kahumbu added, "Once an elephant has died, they will sometimes even cover it up with bushes. It's a really peculiar thing. We don't really understand it, to be honest."
Other studies on animal intelligence have found that elephants in zoos respond positively to the presence of humans (likely because of their intellect), that they have names for each other and that they provide support to sick or injured herd members. If humans wish to keep these sensitive and thoughtful animals alive, the PLOS Sustainability and Transformation article asserts, then they will need to work together in constructive ways that acknowledge the scientific facts.
"Conservation of elephants requires a transboundary management approach to climate change mitigation, cooperation among conservation agencies, and effective partnerships with all relevant stakeholders for conservation," the authors conclude.