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.
Productivity is a poor predictor of plant species richness
Range-wide assessment of livestock grazing across the sagebrush biome
Effectiveness of post-fire seeding at the Fitzner-Eberhardt Arid Land Ecology Reserve, Washington
Effects of resource availability and propagule supply on native species recruitment in sagebrush ecosystems invaded by Bromus tectorum
Ecological influence and pathways of land use in sagebrush
Conservation of greater sage-grouse- a synthesis of current trends and future management
Abundance of introduced species at home predicts abundance away in herbaceous communities
Restoring and rehabilitating sagebrush habitats
Yield responses of ruderal plants to sucrose in invasive-dominated sagebrush steppe of the northern Great Basin
Assessing transportation infrastructure impacts on rangelands: test of a standard rangeland assessment protocol
Final Report for Emergency Stabilization and Rehabilitation Treatment Monitoring of the Keeney Pass, Cow Hollow, Double Mountain, and Farewell Bend Fires
Investigating Seed Longevity of Big Sagebrush (Artemisia tridentata)
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
- Science
Filter Total Items: 13
- 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.
- Multimedia
- 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: 112Productivity is a poor predictor of plant species richness
For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses questioned the gAuthorsPeter B. Adler, Eric W. Seabloom, Elizabeth T. Borer, Helmut Hillebrand, Yann Hautier, Andy Hector, W. Stanley Harpole, Lydia R. O'Halloran, James B. Grace, T. Michael Anderson, Jonathan D. Bakker, Lori A. Biederman, Cynthia S. Brown, Yvonne M. Buckley, Laura B. Calabrese, Cheng-Jin Chu, Elsa E. Cleland, Scott L. Collins, Kathryn L. Cottingham, Michael J. Crawley, Ellen Ingman Damschen, Kendi F. Davies, Nicole M. DeCrappeo, Philip A. Fay, Jennifer Firn, Paul Frater, Eve I. Gasarch, Daneil S. Gruner, Nicole Hagenah, Janneke Hille Ris Lambers, Hope Humphries, Virginia L. Jin, Adam D. Kay, Kevin P. Kirkman, Julia A. Klein, Johannes M.H. Knops, Kimberly J. La Pierre, John G. Lambrinos, Wei Li, Andrew S. MacDougall, Rebecca L. McCulley, Brett A. Melbourne, Charles E. Mitchell, Joslin L. Moore, John W. Morgan, Brent Mortensen, John L. Orrock, Suzanne M. Prober, David A. Pyke, Anita C. Risch, Martin Schuetz, Melinda D. Smith, Carly J. Stevens, Lauren L. Sullivan, Gang Wang, Peter D. Wragg, Justin P. Wright, Louie H. YangRange-wide assessment of livestock grazing across the sagebrush biome
Domestic livestock grazing occurs in virtually all sagebrush habitats and is a prominent disturbance factor. By affecting habitat condition and trend, grazing influences the resources required by, and thus, the distribution and abundance of sagebrush-obligate wildlife species (for example, sage-grouse Centrocercus spp.). Yet, the risks that livestock grazing may pose to these species and their habAuthorsKari E. Veblen, David A. Pyke, Christopher A. Jones, Michael L. Casazza, Timothy J. Assal, Melissa A. FarinhaEffectiveness of post-fire seeding at the Fitzner-Eberhardt Arid Land Ecology Reserve, Washington
In August 2007, the Milepost 17 and Wautoma fires burned a combined total of 77,349 acres (31,302 hectares) of the Fitzner-Eberhardt Arid Land Ecology Reserve (ALE), part of the Hanford Reach National Monument administered by the U.S. Fish and Wildlife Service (USFWS) Mid-Columbia National Wildlife Refuge. In 2009, the USFWS implemented a series of seeding and herbicide treatments to mitigate poteAuthorsTroy A. Wirth, David A. PykeEffects of resource availability and propagule supply on native species recruitment in sagebrush ecosystems invaded by Bromus tectorum
Resource availability and propagule supply are major factors influencing establishment and persistence of both native and invasive species. Increased soil nitrogen (N) availability and high propagule inputs contribute to the ability of annual invasive grasses to dominate disturbed ecosystems. Nitrogen reduction through carbon (C) additions can potentially immobilize soil N and reduce the competitiAuthorsMonica B. Mazzola, Jeanne C. Chambers, Robert R. Blank, David A. Pyke, Eugene W. Schupp, Kimberly G. Allcock, Paul S. Doescher, Robert S. NowakEcological influence and pathways of land use in sagebrush
Land use in sagebrush (Artemisia spp.) landscapes influences all sage-grouse (Centrocer-cus spp.) populations in western North America. Croplands and the network of irrigation canals cover 230,000 km2 and indirectly influence up to 77% of the Sage-Grouse Conservation Area and 73% of sagebrush land cover by subsidizing synanthropic predators on sage-grouse. Urbanization and the demands of human popAuthorsSteven T. Knick, Steven E. Hanser, Richard F. Miller, David A. Pyke, Michael J. Wisdom, Sean P. Finn, E. Thomas Rinkes, Charles J. HennyConservation of greater sage-grouse- a synthesis of current trends and future management
Recent analyses of Greater Sage-Grouse (Centrocercus urophasianus) populations indicate substantial declines in many areas but relatively stable populations in other portions of the species? range. Sagebrush (Artemisia spp.) habitats neces-sary to support sage-grouse are being burned by large wildfires, invaded by nonnative plants, and developed for energy resources (gas, oil, and wind). ManagemenAuthorsJohn W. Connelly, Steven T. Knick, Clait E. Braun, William L. Baker, Erik A. Beever, Thomas J. Christiansen, Kevin E. Doherty, Edward O. Garton, Christian A. Hagen, Steven E. Hanser, Douglas H. Johnson, Matthias Leu, Richard F. Miller, David E. Naugle, Sara J. Oyler-McCance, David A. Pyke, Kerry P. Reese, Michael A. Schroeder, San J. Stiver, Brett L. Walker, Michael J. WisdornAbundance of introduced species at home predicts abundance away in herbaceous communities
Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countriAuthorsJennifer Firn, Joslin L. Moore, Andrew S. MacDougall, Elizabeth T. Borer, Eric W. Seabloom, Janneke HilleRisLambers, W. Stanley Harpole, Elsa E. Cleland, Cynthia S. Brown, Johannes M.H. Knops, Suzanne M. Prober, David A. Pyke, Kelly A. Farrell, John D. Bakker, Lydia R. O'Halloran, Peter B. Adler, Scott L. Collins, Carla M. D'Antonio, Michael J. Crawley, Elizabeth M. Wolkovich, Kimberly J. La Pierre, Brett A. Melbourne, Yann Hautier, John W. Morgan, Andrew D.B. Leakey, Adam Kay, Rebecca McCulley, Kendi F. Davies, Carly J. Stevens, Cheng-Jin Chu, Karen D. Holl, Julia A. Klein, Phillip A. Fay, Nicole Hagenah, Kevin P. Kirkman, Yvonne M. BuckleyRestoring and rehabilitating sagebrush habitats
Less than half of the original habitat of the Greater Sage-Grouse (Centrocercus uropha-sianus) currently exists. Some has been perma-nently lost to farms and urban areas, but the remaining varies in condition from high quality to no longer adequate. Restoration of sagebrush (Artemisia spp.) grassland ecosystems may be pos-sible for resilient lands. However, Greater Sage-Grouse require a wide varieAuthorsDavid A. PykeYield responses of ruderal plants to sucrose in invasive-dominated sagebrush steppe of the northern Great Basin
Restoration of sagebrush-steppe plant communities dominated by the invasive ruderals Bromus tectorum (cheatgrass) and Taeniatherum caput-medusae (medusahead) can be facilitated by adding carbon (C) to the soil, stimulating microbes to immobilize nitrogen (N) and limit inorganic N availability. Our objectives were to determine responses in (1) cheatgrass and medusahead biomass and seed production;AuthorsJessi Brunson, David A. Pyke, Steven S. PerakisAssessing transportation infrastructure impacts on rangelands: test of a standard rangeland assessment protocol
Linear disturbances associated with on- and off-road vehicle use on rangelands has increased dramatically throughout the world in recent decades. This increase is due to a variety of factors including increased availability of all-terrain vehicles, infrastructure development (oil, gas, renewable energy, and ex-urban), and recreational activities. In addition to the direct impacts of road developmeAuthorsMichael C. Duniway, Jeffrey E. Herrick, David A. Pyke, David ToledoFinal Report for Emergency Stabilization and Rehabilitation Treatment Monitoring of the Keeney Pass, Cow Hollow, Double Mountain, and Farewell Bend Fires
A strategy for monitoring post-fire seedings in the sagebrush steppe of the Intermountain West was developed and used to monitor four example fires in the Vale, Oregon District of the Bureau of Land Management (BLM). We began to develop a potential approach by (1) reviewing previous vegetation monitoring manuals produced by the Federal government to determine what techniques and approaches had beeAuthorsTroy A. Wirth, David A. PykeInvestigating Seed Longevity of Big Sagebrush (Artemisia tridentata)
The Intermountain West is dominated by big sagebrush communities (Artemisia tridentata subspecies) that provide habitat and forage for wildlife, prevent erosion, and are economically important to recreation and livestock industries. The two most prominent subspecies of big sagebrush in this region are Wyoming big sagebrush (A. t. ssp. wyomingensis) and mountain big sagebrush (A. t. ssp. vaseyana).AuthorsUpekala C. Wijayratne, David A. PykeNon-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.
- News
Filter Total Items: 19
*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