Document Type

Greater Yellowstone Ecosystem Report

First Page


Last Page



Advancing global climate change and associated desiccation of temperate and boreal forests, exacerbated by extensive clear-cutting, may increase poisoning of aquatic ecosystems with high levels of contaminants, especially Hg. We report on contaminants identified in nestling bald eagles and wildland firefighters of the Teton Ecosystem (Grand Teton National Park (GTNP) and the Snake River Unit (SRU), Wyoming) during summers of 2006, 2007 and 2008. In bald eagles, we focus primarily on mercury (Hg), lead (Pb), and selenium (Se) because each was detected in all nestlings during all summers at moderate levels. In wildland firefighters, we report primarily on Hg due to potential contamination from Hg when fighting fires and ingesting smoke and particulates produced by those fires. We feel that studying Hg both in the eagles and humans simultaneously is a better indicator of the general health of the environment than studying them separately. Both humans and bald eagles occupy top tiers on the food web, and intricately reflect the status of the environment. Results of the bald eagle analyses showed trends indicating increases in Hg and Pb from 2006 to 2007, and decreases from 2007 to 2008. Selenium essentially remained constant from 2006 to 2007 and increased from 2007 to 2008. In wildland firefighters, Hg appears to be elevated in those firefighters who are exposed to significant levels of smoke and particulates, both in 2007 and 2008. Conjectures about firefighters, however, are not statistically significant due to small sample sizes and logistical problems. Encouraging trends in bald eagle contaminant levels from 2007 to 2008 suggest reduction (or stabilization) of contaminant concentrations in the Teton Ecosystem. We also encourage the continued elimination of Pb attributable to humans (lead ammunition, lead shot, etc.) from the Teton Ecosystem. We encourage periodic monitoring of contaminants in the Teton Ecosystem, minimally at five-year intervals (Harmata 1996), unless unexpected events mandate more immediate monitoring. In wildland firefighters, we suggest a well-designed, comprehensive research study for summer 2009, to immediately address future ecological issues that are emerging due to climate change.