The Secret of How Elephant Societies Remain Intact Despite the Poaching Crisis
As global demand for illegal ivory soared last year, black market prices hit $1,500 per ounce, making elephant tusks more valuable than gold. The ongoing poaching epidemic resulted in the death of 100,000 elephants between 2010 and 2012.
Poachers target large males first, as they sport the biggest tusks, and then take out older females. That would seem to fracture elephants’ matriarchal society, but a new study finds that the pachyderms’ extended families are more resilient than was thought.
“The structure of elephant society is really complex, especially when it comes to females,” said Shifra Goldenberg, a doctoral student at Colorado State University, who coauthored the study published Thursday in the journal Current Biology. “As a female elephant, you’re rarely alone; you’re usually with your relatives and with your extended groups.”
The researchers wanted to know what happened when poachers removed older females from these intricate social structures. They reviewed 16 years of data on elephants that were part of a population in Kenya’s Samburu National Reserve maintained by the nonprofit group Save the Elephants. The data tracked which individual elephants (identified by ear shape, body markings, or other unique characteristics) were associating with other elephants. “Basically, we figured out groups of who was hanging out together,” said Goldenberg.
Despite a turnover of about 70 percent in the elephant group, the researchers found that the animals’ social structure was maintained even when matriarchs were killed. That mainly happened when the middle-aged females—now the oldest in the group—stepped up to fill leadership roles.
“It shows that elephants are socially resilient,” Goldenberg said. “In a highly social species, they depend on social bonds, so the fact that we haven’t seen social collapse is good news.”
She said that the younger females had enough social knowledge to recreate patterns they learned from their older female relatives
But there are other implications to losing the oldest females. It’s still not known how older females affect the survival of elephant calves, for instance. And there are other questions. “What are the other implications of losing your matriarch?” Goldenberg said. “Sure, these elephants are maintaining some kind of social structure, but what does it mean for their ranging patterns?”
Older females are also important information hubs for the group, carrying ecological knowledge from many years of experience—such as where to find distant water holes in times of drought or distinguishing threat calls from other types of communication. “We may see during a drought period that they don’t do as well,” said Goldenberg.
Elephants aren’t the only species that relies on a matriarch’s deep ecological experience. A study of orcas published in the journal Current Biology earlier this year found that in years when salmon stocks were low, older females were more likely to lead pods to find food.