David A Pyke
I am a scientist emeritus at the Forest and Rangeland Ecosystem Science Center. My research interests include population ecology of native and invasive plants in the Intermountain West, monitoring protocols for ecosystem integrity on wild lands, and restoration ecology of native plants on disturbed and invaded lands.
I am involved with a few of my former projects. I am completing the ten-year analysis of the SageSTEP sagebrush – cheatgrass sites. I plan to assist and continue to provide guidance to new scientists who are now leading this long-term project. I am providing guidance and insights for two other on-going projects - The Field of Sagebrush Dreams project and the Mojave grazing removal project. Field of Dreams is an attempt to transplant sagebrush and create patches of sagebrush that will be used by Greater Sage-grouse for nesting within 5 years of a fire removing sagebrush from former nesting sites. The Mojave project is examining vegetation changes after livestock grazing was removed from locations on the Mojave National Preserve 20 years ago. Amongst these interests, my wife and I plan to travel in our teardrop trailer and see other landscapes in the US and Canada and to travel internationally to enjoy new cultures. In addition, we plan to make regular visits to our home in Honolulu.
Professional Experience
1996 – 2021: Supervisory Research Ecologist, U.S. Geological Survey, Forest & Rangeland Ecosystem Science Center, Corvallis, OR
1996 – 1999: Assistant Center Director, U.S. Geological Survey, Forest & Rangeland Ecosystem Science Center, Corvallis, OR
1993 – 1996: Research Rangeland Ecologist, National Biological Survey/Service, Forest & Rangeland Ecosystem Science Center, Corvallis, OR
1992 – 1993: Research Rangeland Ecologist, Bureau of Land Management, Pacific Forest & Basin Rangeland Systems Cooperative Research & Technology Unit, Corvallis, OR
1987 – 1992: Assistant Professor, Department of Range Science, Utah State University, Logan, UT
Education and Certifications
Ph.D., Botany, Washington State University, Pullman, WA (1983)
M.S., Forest and Range Management, Washington State University, Pullman, WA (1977)
B.S., Range Management (Wildlife option), Washington State University, Pullman, WA (1976)
Affiliations and Memberships*
Ecological Society of America
British Ecological Society
Society for Ecological Restoration
Society for Range Management
Science and Products
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Climate change-induced vegetation shifts lead to more ecological droughts despite projected rainfall increases in many global temperate drylands
Patterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales
Science framework for conservation and restoration of the sagebrush biome: Linking the Department of the Interior’s Integrated Rangeland Fire Management Strategy to long-term strategic conservation actions, Part 1. Science basis and applications
Monitoring protocols: Options, approaches, implementation, benefits
Fungal and bacterial contributions to nitrogen cycling in cheatgrass-invaded and uninvaded native sagebrush soils of the western USA
Using resilience and resistance concepts to manage persistent threats to sagebrush ecosystems and greater sage-grouse
Climate change reduces extent of temperate drylands and intensifies drought in deep soils
Restoration handbook for sagebrush steppe ecosystems with emphasis on greater sage-grouse habitat—Part 3. Site level restoration decisions
Using resilience and resistance concepts to manage threats to sagebrush ecosystems, Gunnison sage-grouse, and Greater sage-grouse in their eastern range: A strategic multi-scale approach
Filling the interspace—restoring arid land mosses: source populations, organic matter, and overwintering govern success
Land uses, fire, and invasion: Exotic annual Bromus and human dimensions
Science framework for the conservation and restoration strategy of DOI secretarial order 3336: Utilizing resilience and resistance concepts to assess threats to sagebrush ecosystems and greater sage-grouse, prioritize conservation and restoration actions,
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
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- Data
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
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- Publications
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Filter Total Items: 112Climate change-induced vegetation shifts lead to more ecological droughts despite projected rainfall increases in many global temperate drylands
Drylands occur world-wide and are particularly vulnerable to climate change since dryland ecosystems depend directly on soil water availability that may become increasingly limited as temperatures rise. Climate change will both directly impact soil water availability, and also change plant biomass, with resulting indirect feedbacks on soil moisture. Thus, the net impact of direct and indirect climAuthorsBritta Tietjen, Daniel R. Schlaepfer, John B. Bradford, William K. Laurenroth, Sonia A. Hall, Michael C. Duniway, Tamara Hochstrasser, Gensuo Jia, Seth M. Munson, David A. Pyke, Scott D. WilsonPatterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales
Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (AuthorsAdrian P. Monroe, Cameron L. Aldridge, Timothy J. Assal, Kari E. Veblen, David A. Pyke, Michael L. CasazzaScience framework for conservation and restoration of the sagebrush biome: Linking the Department of the Interior’s Integrated Rangeland Fire Management Strategy to long-term strategic conservation actions, Part 1. Science basis and applications
The Science Framework is intended to link the Department of the Interior’s Integrated Rangeland Fire Management Strategy with long-term strategic conservation actions in the sagebrush biome. The Science Framework provides a multiscale approach for prioritizing areas for management and determining effective management strategies within the sagebrush biome. The emphasis is on sagebrush (Artemisia spAuthorsJeanne C. Chambers, Jeffrey L. Beck, John B. Bradford, Jared Bybee, Steve Campbell, John Carlson, Thomas J Christiansen, Karen J. Clause, Gail Collins, Michele R. Crist, Jonathan B. Dinkins, Kevin Doherty, Fred Edwards, Shawn Espinosa, Kathleen A. Griffin, Paul Griffin, Jessica R. Haas, Steve E. Hanser, Douglas W. Havlina, Kenneth F. Henke, Jacob D. Hennig, Linda A Joyce, Francis F. Kilkenny, Sarah M Kulpa, Laurie L Kurth, Jeremy D Maestas, Mary E. Manning, Kenneth E. Mayer, Brian A. Mealor, Clinton McCarthy, Mike Pellant, Marco A. Perea, Karen L. Prentice, David A. Pyke, Lief A. Wiechman, Amarina WuenschelMonitoring protocols: Options, approaches, implementation, benefits
Monitoring and adaptive management are fundamental concepts to rangeland management across land management agencies and embodied as best management practices for private landowners. Historically, rangeland monitoring was limited to determining impacts or maximizing the potential of specific land uses—typically grazing. Over the past several decades, though, the uses of and disturbances to rangelanAuthorsJason W. Karl, Jeffrey E. Herrick, David A. PykeFungal and bacterial contributions to nitrogen cycling in cheatgrass-invaded and uninvaded native sagebrush soils of the western USA
AimThere is interest in determining how cheatgrass (Bromus tectorum L.) modifies N cycling in sagebrush (Artemisia tridentata Nutt.) soils of the western USA.MethodsTo gain insight into the roles of fungi and bacteria in N cycling of cheatgrass-invaded and uninvaded sagebrush soils, the fungal protein synthesis inhibitor, cycloheximide (CHX), and the bacteriocidal compound, bronopol (BRO) were comAuthorsNicole DeCrappeo, Elizabeth J. DeLorenze, Andrew T Giguere, David A. Pyke, Peter J. BottomleyUsing resilience and resistance concepts to manage persistent threats to sagebrush ecosystems and greater sage-grouse
Conservation of imperiled species often demands addressing a complex suite of threats that undermine species viability. Regulatory approaches, such as the US Endangered Species Act (1973), tend to focus on anthropogenic threats through adoption of policies and regulatory mechanisms. However, persistent ecosystem-based threats, such as invasive species and altered disturbance regimes, remain criticAuthorsJeanne C. Chambers, Jeremy D. Maestas, David A. Pyke, Chad S. Boyd, Mike Pellant, Amarina WuenschelClimate change reduces extent of temperate drylands and intensifies drought in deep soils
Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. While drylands as a whole are expected to increase in extent and aridity in coming decades, temperature and precipitation forecasts vary by latitude and geographic region suggesting different trajectories for tropical, subtropical, and temperate drylands. Uncertainty in the future of tropical and subtropAuthorsDaniel R. Schlaepfer, John B. Bradford, William K. Lauenroth, Seth M. Munson, Britta Tietjen, Sonia A. Hall, Scott D. Wilson, Michael C. Duniway, Gensuo Jia, David A. Pyke, Ariuntsetseg Lkhagva, Khishigbayar JamiyansharavRestoration handbook for sagebrush steppe ecosystems with emphasis on greater sage-grouse habitat—Part 3. Site level restoration decisions
Sagebrush steppe ecosystems in the United States currently (2016) occur on only about one-half of their historical land area because of changes in land use, urban growth, and degradation of land, including invasions of non-native plants. The existence of many animal species depends on the existence of sagebrush steppe habitat. The greater sage-grouse (Centrocercus urophasianus) depends on large laAuthorsDavid A. Pyke, Jeanne C. Chambers, Mike Pellant, Richard F. Miller, Jeffrey L. Beck, Paul S. Doescher, Bruce A. Roundy, Eugene W. Schupp, Steven T. Knick, Mark Brunson, James D. McIverUsing resilience and resistance concepts to manage threats to sagebrush ecosystems, Gunnison sage-grouse, and Greater sage-grouse in their eastern range: A strategic multi-scale approach
This report provides a strategic approach developed by a Western Association of Fish and Wildlife Agencies interagency working group for conservation of sagebrush ecosystems, Greater sage-grouse, and Gunnison sage-grouse. It uses information on (1) factors that influence sagebrush ecosystem resilience to disturbance and resistance to nonnative invasive annual grasses and (2) distribution and relatAuthorsJeanne C. Chambers, Jeffrey L. Beck, Steve Campbell, John Carlson, Thomas J. Christiansen, Karen J. Clause, Jonathan B. Dinkins, Kevin E. Doherty, Kathleen A. Griffin, Douglas W. Havlina, Kenneth F. Mayer, Jacob D. Hennig, Laurie L. Kurth, Jeremy D. Maestas, Mary E. Manning, Brian A. Mealor, Clinton McCarthy, Marco A. Perea, David A. PykeFilling the interspace—restoring arid land mosses: source populations, organic matter, and overwintering govern success
Biological soil crusts contribute to ecosystem functions and occupy space that could be available to invasive annual grasses. Given disturbances in the semiarid shrub steppe communities, we embarked on a set of studies to investigate restoration potential of mosses in sagebrush steppe ecosystems. We examined establishment and growth of two moss species common to the Great Basin, USA: Bryum argenteAuthorsLea Condon, David A. PykeLand uses, fire, and invasion: Exotic annual Bromus and human dimensions
Human land uses are the primary cause of the introduction and spread of exotic annual Bromus species. Initial introductions were likely linked to contaminated seeds used by homesteading farmers in the late 1880s and early 1900s. Transportation routes aided their spread. Unrestricted livestock grazing from the 1800s through the mid-1900s reduced native plant competitors leaving large areas vulnerabAuthorsDavid A. Pyke, Jeanne C. Chambers, Jeffrey L. Beck, Matthew L. Brooks, Brian A. MealorScience framework for the conservation and restoration strategy of DOI secretarial order 3336: Utilizing resilience and resistance concepts to assess threats to sagebrush ecosystems and greater sage-grouse, prioritize conservation and restoration actions,
The Science Framework for the Conservation and Restoration Strategy of the Department of the Interior, Secretarial Order 3336 (SO 3336), Rangeland Fire Prevention, Management and Restoration, provides a strategic, multiscale approach for prioritizing areas for management and determining effective management strategies across the sagebrush biome. The emphasis of this version is on sagebrush ecosystAuthorsJeanne C. Chambers, Steve Campbell, John Carlson, Jeffrey L. Beck, Karen J. Clause, Jonathan B. Dinkins, Kevin E. Doherty, Shawn Espinosa, Kathleen A. Griffin, Thomas J. Christiansen, Michele R. Crist, Steve E. Hanser, Douglas W. Havlina, Kenneth F. Henke, Jacob D. Hennig, Laurie L. Kurth, Jeremy D. Maestas, Kenneth E. Mayer, Mary E. Manning, Brian A. Mealor, Clinton McCarthy, Mike Pellant, Karen L. Prentice, Marco A. Perea, David A. Pyke, Lief A. Wiechman, Amarina WuenschelNon-USGS Publications**
Francis, M.G., Pyke, D.A., 1996, Crested wheatgrass-cheatgrass seedling competition in a mixed-density design: Journal of Range Management, v. 49, no. 5, p. 432-438.Tanaka, J.A., Pyke, D.A., 1996, Introduction to the Sustaining Rangeland Ecosystems Symposium In Edge, W.D., Olson-Edge, S.L., eds., Proceedings of the Sustaining Rangeland Ecosystems Symposium: Special Report 953, Corvallis, OR, Oregon State University, Agricultural Experiment Station, p. 1-2.Huber-Sannwald, E., Pyke, D.A., Caldwell, M.M., 1996, Morphological plasticity following species-specific recognition and competition in two perennial grasses: American Journal of Botany, v. 83, no. 7, p. 919-931.Pyke, D.A., 1995, Population diversity with special reference to rangeland plants In West, N.E., ed., Biodiversity of Rangelands: Logan, Utah, College of Natural Resources, Utah State University, p. 21-32.Pyke, D.A., Novak, S.J., 1994, Cheatgrass demography-establishment attributes, recruitment, ecotypes, and genetic variability: U.S. Department of Agriculture, Forest Service, Intermountain Research Station General Technical Report INT-GTR-313, p. 12-21.Pyke, D.A., 1994, Ecological significance of seed banks with special reference to alien annuals: U.S. Department of Agriculture, Forest Service, General Technical Report INT-GTR-313, p. 197-201.Borman, M.M., Pyke, D.A., 1994, Successional theory and the desired plant community approach: Rangelands, v. 16, no. 2, p. 82-84.Pyke, D.A., Borman, M.M., 1993, Problem analysis for the Vegetation Diversity Project - A research and demonstration program to restore and maintain native plant diversity on deteriorated rangelands of the Great Basin and Columbia Plateau: US, Bureau of Land Management, Oregon State Office Technical Note OR-936-01, p. 100.Pyke, D.A., Thompson, J.N., 1986, Statistical analysis of survival, and removal rate experiments: Ecology, no. 67, p. 240-245.**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
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*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government