It was an idea whose popularity skyrocketed. In 1998, only 25 horses lived in Wolong. By 2008, 350 horses lived there in 20 to 30 herds.
To understand the scope of the problem, Hull and her colleagues put the same type of GPS collars they were using to track pandas on one horse in each of the four herds they studied. Then over a year they compared their activity with that of three collared adult pandas in some of the same areas and combined it with habitat data.
They discovered that horses are indeed big on bamboo and also are drawn to the same sunny, gently sloped spots as pandas. Pandas and horses eat about the same amount of bamboo, but a herd of more than 20 horses made for a feeding frenzy, decimating areas the reserve was established to protect.
This horse problem has been resolved. The researchers presented their findings to Wolong's managers, who have since banned horses from the reserve. But Hull and Liu note that this work has shed light on how competitive livestock can be in sensitive habitat an issue that is repeated across the globe.
"Livestock affect most of the world's biodiversity hotspots," Liu said. "They make up 20 percent of all of the earth's land mammals and therefore monopolize key resources needed to maintain the earth's fragile ecosystems."
|Contact: Jamie DePolo|
Michigan State University