Greater Yellowstone Ecosystem - Whitebark Pinebeetle

State: Montana, Wyoming
Description:

The whitebark, being both a foundation and a keystone species, has great significance to the entire Greater Yellowstone Ecosystem, and implications on how the region will respond to climate change.  These forests are crucial for distribution of winter snow and attenuation of snow-melt water release in the spring. Peak stream flow would occur earlier and be of shorter duration without the protective shading provided by whitebark pine.

 

Many wildlife species depend on the whitebark for their survival. Whitebark depends almost exclusively on Clark’s nutcracker for natural regeneration (Tomback 2001), so the loss of most mature whitebark pines in a stand could result in no future regeneration if the residual live trees cannot support a nutcracker population. Whitebark pine nuts are a critical food source for grizzly bears, attracting the bears to remote high-elevation areas and thus, away from people. In response to the tree’s recent decline (74%), the animals could switch to eating more meat or find other plants as a substitution

 

A beetle epidemic that's killing trees across the Rocky Mountain region has taken an especially heavy toll on whitebark pine trees in the Yellowstone Ecosystem. Warming winter temperatures have allowed the mountain pine beetle to thrive in previously inhospitable, high-elevation white bark pine forests. Active human fire suppression has created prime forest conditions for the beetle across the region.

 

In 2009, EcoFlight participated in a full scientific aerial survey of the entire Greater Yellowstone Ecosystem to study the extent of the pine beetle infestation. The study indicates nearly 85 percent of Whitebark Pine stands in Greater Yellowstone are dead or dying and forecasts that the Whitebark will be functionally dead in Greater Yellowstone within the next decade.

In December 2013, federal and state officials recommended that the animals' Endangered Species Act protections be taken away. The move responds to a major push by Idaho, Montana and Wyoming to take over management of bears and hold sport hunts, as they've done with wolves.

But the infestation has huge consequences for the region. Already, grizzly bears, re-listed in 2010 under the federal Endangered Species Act, are moving to lower elevations in search of alternative food, bringing them into conflict with humans. The loss of high elevation forests leaves the surrounding countryside more vulnerable to avalanches and early, heavy spring runoff. Climate change is also playing a role in another source of food for the grizzlies – elk, which are expected to decline due to drought. The recent state decision doesn’t take these effects into account.

 

In 2011 the U.S. Fish & Wildlife Service concluded that the threats whitebark faces, including climate change, are of such a high magnitude and are so pressing that whitebark pine should be listed as threatened or endangered. Higher priorities and a lack of funding have kept the Service from listing the species under the Endangered Species Act thus far and federal agencies are struggling with the large scale implications of the situation.


EcoFlight Across America - The Mountain Pinebeetle 2009 from EcoFlight on Vimeo.