Despite the appearance of prairie dogs, a new study on the adorable animals reveals a very common and disturbing behavior among them: killing baby squirrels in order to maintain a fat food supply. The finding is shocking because prairie dogs are herbivorous creatures, which are not known for their homicidal behavior. In fact, the finding marks the first time that this kind of behavior has ever been seen in herbivores.
"In my 43 years of research, this is perhaps the most provocative, puzzling, and far-reaching discovery I've ever made," said John Hoogland, co-author of the study. "The results are just staggering."
After witnessing one instance of the violent behavior, Hoogland and his team committed to observing the behavior of white-tailed prairie dogs. Over the course of five years, his team observed 101 ground squirrel murders and 62 suspected cases, revealing that they typically occurred in May, when these squirrels emerged from their nests and began their summer hunt for food.
"Prairie dogs will chase ground squirrels - usually babies - and if they catch them, they shake them violently," Hoogland said. "While they're shaking, they're biting the back of the neck to sever the vertebral column. Sometimes they grab by the head and literally de-brain the baby. It's violent, savage, and awful."
One of the leading motives for these murders is believed to be the systematic elimination of competition for food. Hoogland and his team found that the survival rates of killers and non-killers were telling: those that killed had much better odds of living than those who didn't.
Amazingly, the penchant for killing in these rodents was found to be the only factor connected to offspring success, suggesting that baby prairie dogs likely owe their murderous parents for living.
"The condition of the female, her longevity - the factors that normally influence [success] - none of them apply to this case," said Charles Brown, another co-author of the study. "It seems to me is that there are major, major benefits to killing these ground squirrels."
Nevertheless, further research needs to be conducted to in order to validate the food competition theory, as there is also the possibility that prairie dogs live in areas with more vegetation, meaning more squirrels and, in turn, a higher likelihood of conflicts over food.
The findings were published in the March 23 issue of the Proceedings of the Royal Society B: Biological Sciences.