The National Park Service conducts ongoing monitoring in winter for soundscapes, air quality, wildlife, and personal health and exposure. The agency uses such monitoring as part of its ongoing winter use management. Below is a list of annual reports for each of these subjects.

Natural Soundscape Monitoring in Yellowstone National Park, December 2005 -March 2006 (2.6 MB pdf)

Natural Soundscape Monitoring in Yellowstone National Park, December 2004-March 2005 (1.01 MB pdf)

Natural Soundscape Monitoring in Yellowstone National Park, December 2003-March 2004 (1.04 MB pdf)

Winter Air Quality Study in Yellowstone National Park 2005-2006 (3.1 MB pdf)

Winter Air Quality Study, 2004-2005 ( 1.58MB pdf)

Air Quality Analysis of Snowmobile and Snowcoach Emissions, July 2004 (735 KB pdf) 

Wildlife Reports
Ecology of Bison Movements in and Beyond YNP

Wildlife Responses to Motorized Winter Recreation in Yellowstone: 2007 Annual Report (December 18, 2006 through March 29, 2007)(142 Kb pdf)

Behavioral Responses of Wildlife to Snowmobiles and Coaches in Yellowstone (2006) - (369 KB pdf)

Wildlife Responses to Winter Recreation in Yellowstone National Park-Figures 2006 (Final Draft) - (446 KB pdf)

Wildlife Responses to Winter Recreation in Yellowstone National Park-Appendices 2006 (Final Draft) - (348 KB pdf)

Wildlife Responses to Motorized Winter Recreation in Yellowstone National Park, 2005 Annual Report (713 KB pdf)

Wildlife Responses to Winter Recreation in Yellowstone National Park, 2004 Annual Report (1.57 MB pdf)

Evaluating Wildlife Responses to Winter Human Use in Yellowstone National Park, Winter 2003-04 (233 KB pdf)

Wildlife Responses to Motorized Winter Recreation in Yellowstone National Park, 2003 Annual Report (1.81 MB pdf)

Evaluating Wildlife Responses to Winter Human Use in Yellowstone National Park, Winter 2002-03 (230 KB pdf)

The Effects of Winter Recreation on Wildlife of the Greater Yellowstone Area: A Literature Review and Assessment (1.5 MB pdf)

Yellowstone Winter Use Personal Exposure Monitoring Report June 2006 (Draft) (1.79 MB pdf)

Yellowstone Winter Use Personal Exposure Monitoring Appendices June 2006 (Draft) (14.2 MB pdf)

Winter Use Personal Exposure Monitoring Report, June 2005 (10.5 MB pdf)

Summer Entrance Employee Air Monitoring Report, August 2005 (6.8 MB pdf)

In-use Emission Measurements of Snowmobiles and Snowcoaches in Yellowstone National Park, January 2006 (5.7 MB pdf)

Effects of Snowmobile Emissions on the Chemistry of Snowmelt Runoff in Yellowstone National Park (792 KB pdf)

Spatial Variations of Volatile Organic Compounds Associated with Snowmobile Use in YNP Sive, et al, October 25, 2003 (986 KB pdf)

Socioeconomic Reports
Final Report - Economic Analysis of Temporary Regulations of Snowmobile Use in the Greater Yellowstone Area (October 2004, 1.5 MB pdf)

Economic Analysis of Temporary Regulations on Snowmobile Use in the Greater Yellowstone Area - August 2004 (1.8 MB pdf)

Economic Impact Analysis of the Temporary Winter Use Plan for Yellowstone, Grand Teton, national parks, and J.D. Rockefeller Jr. Memorial Parkway, August 2004 (325 KB pdf)

Winter 1998-1999 Visitor Survey Yellowstone National Park, Grand Teton National Park, and the Greater Yellowstone Area. Final Report. John Duffield and Christopher Neher, Bioeconomics, Inc. Missoula, Montana, May 2000 (957KB pdf)

Winter Visit and Visitor Characteristics of Yellowstone National Park, Final Report. William T. Borrie, Wayne A. Freimund, Mae Davenport, University of Montana and Robert Manning, William Valliere, and Ben Wang, University of Vermont. 1999.

Winter Visitor Use Management: Multi-agency Assessment, 1999