Wolves, Monkeys: Hunting Allies in Ethiopia
In Rudyard Kipling's The Jungle Book, the man-child Mowgli learns that monkeys, with their seemingly erratic behavior, produce nothing good. But a Dartmouth-led study has found that solitary, and endangered, Ethiopian wolves hunt more effectively in the presence of grazing gelada monkey herds.
Consistently nonthreatening toward the monkeys, Ethiopian wolves spend time among the geladas, monkeys that are close relatives of baboons, and they resist opportunities to attack juvenile geladas in order to seek out their true prey, rodents, researchers found.
Gelada monkeys eat grass and certain herbs, living in herds of between 200 and 1000 individuals. Ethiopian wolves are the world's rarest canids, with between 300 and 500 remaining in the wild.
Researchers followed a band of about 200 gelada monkeys on the Guassa Plateau in north central Ethiopia from 2006 to 2011. They found that the monkeys would not typically move when wolves arrived, even when wolves were in the middle of the herd--in 68 percent of encounters, monkeys did not move; in 11 percent of encounters, monkeys moved no less than 3.04 feet. However, the geladas fled for the cliffs when they encountered aggressive domestic dogs, the study found.
Not only that, but the Ethiopian wolves hunted more successfully around the monkeys. Wolves had a foraging success rate of 66.7 percent of attempts when among the gelada monkeys, versus a success rate of 25 percent when by themselves. Researchers think the success rate may be attributed to the rodents being flushed out by the monkey herd, or to a diminished ability for the rodents to notice predators when distracted by the grazing monkeys.