trees

In early December, the National Resource Defense Council submitted petitions to have the whitebark pine listed as an endangered species under the Endangered Species Program. In light of this petition, it seems timely to point toward several interesting science articles available regarding whitebark pine, the species that depend on it, and the potential impacts of climate change on the species.
Several species have close relationships with whitebark pine. In the early 1980's, the symbiotic relationship between whitebark pine and Clark's nutcracker birds was established: the birds help disperse seeds (which are not released from the cone and spread by wind) by creating seed caches for their winter food supply. The seeds that are not eaten have a chance to germinate. Because of the high fat and protein content, grizzly and black bears also use whitebark pine seeds as a significant component of their annual calorie intake.
Journal Article: “Use of sulfur and nitrogen stable isotopes to determine the importance of whitebark pine nuts to Yellowstone grizzly bears”, Laura Felicetti, et al.
Journal Article: One of several articles published in 1982 that established the interconnection between whitebark pine and Clark's nutcracker birds.
Two major threats faced by whitebark pine trees, and cited in the NRDC press release, are mountain pine beetles (earlier post) and white pine blister rust. Mountain pine beetles, a native species, bore under a tree's bark and disrupt the nutrient flow, causing fairly quick tree mortality. Blister rust, a non-native fungus, is recognizable by its orange color.
Journal Article: “The influence of white pine blister rust on seed dispersal in whitebark pine”, authored by Shawn McKinney and Diana Tomback
NRDC press release: Article on the NRDC petition to have the whitebark pine listed as an endangered species.
Whitebark Pine Ecosystem Foundation: While this nonprofit organization does have an advocacy bent, they also provide excellent scientific information on the whitebark pine. The Director of their Board of Directors is University of Colorado Professor Diana Tomback, a prominent whitebark pine scientist, with more than a handful of scientists filling in other board positions.
General Audience Article: A general introduction to whitebark pine trees, the animals they support, and the threats they face.
Recommended Book: A remarkably complete survey of the science on whitebark pine.

The Clark Fork Coalition released the report Low Flows, Hot Trout in July 2008 in partnership with the National Wildlife Federation. While the report covers science and policy/action (policy/action is not the purpose of this blog), the science section of the report is a nice overview of climate change science and impacts for the Greater Yellowstone Ecosystem. Though the Clark Fork Watershed is not in the GYE proper, the issues faced there - e.g., increasing temperatures, earlier snowmelt and runoff, higher likelihood of wildfire and insect outbreaks - are the same as those in the GYE. Also, many of the studies referenced in the report look at all of Montana.

After looking at the Low Flows, Hot Trout report, check out these science sources:

Journal Article: The report reference list does include a Phil Mote publication looking at snowpack. This article, however, is more recent and covers a larger area of the west.
Journal Article: One more Phil Mote journal article looking at snowpack trends.

BSI resource: Lisa Graumlich, the former executive director for the Big Sky Institute, published work with a student and colleague looking at climate change impacts on conifer distribution in the GYE.

IPCC Report: The Clark Fork Coalition's report refers to the Intergovernmental Panel on Climate Change (IPCC) and their work several times. This summary document by the IPCC explores the scientific basis for climate change understanding.

The New York Times recently published an article on the impact that mountain pine beetles are having on pine forests throughout the Rockies, including a video piece. These native beetles have flourished recently thanks to a number of factors, including mild winters; if temperatures are cold enough many larva are killed during winter. Trees experiencing stress (e.g., drought, overcrowding, or old age) are also susceptible to mountain pine beetle outbreaks. Not surprisingly, recent research suggests that as the climate warms, we can expect to see mountain pine beetle outbreaks at higher latitudes. This also reflects the shifting of host ecosystems as the climate changes.
Journal Article: A look beyond trees, to how mountain pine beetle outbreaks will affect the carbon cycle under a changing climate.