“Clark’s Nutcracker is a keystone species, whitebark pine is a keystone species, and they’re both in a key mutualism in this ecosystem,” she says.
Keystone species are plants or animals that are so critical to an ecosystem that the landscape would dramatically change without them. In the Greater Yellowstone Ecosystem, nutcrackers rely on whitebark pines as a crucial food source, the pines rely on nutcrackers to disperse and plant their seeds, and more than 100 other species of plants and animals benefit from that mutualism between tree and bird. But the web is at risk of unraveling. Whitebark pines have suffered massive mortalities from the deadly convergence of blister rust disease and mountain pine beetle outbreaks. Nutcracker populations have declined across half their range since 2003, according to Breeding Bird Survey data. The ripple effects extend throughout the ecosystem, from disappearing forests on mountain heights to the loss of a major food resource for grizzly bears.
Today, Schaming is back on one of her study sites with a new technology, solar-powered satellite tags, to open up a new chapter of her research. She’s searching for ways to keep the nutcracker– whitebark mutualism intact. But first, she’s got to trap a bird.
Excerpt from Gustave Axelson's article "Nutcrackers, Whitebark Pine and a Bond That Holds an Ecosystem Together"