Gregor Auble, Ph.D.
Gregor Auble is a Research Ecologist at the Fort Collins Science Center in northern Colorado. Greg obtained a Ph.D in Ecology at the University of Georgia in 1982 and holds professional certifications of Senior Ecologist from the Ecological Society of America and Professional Wetland Scientist from the Society of Wetlands Scientists. Greg's work has spanned ecological modeling in the context of adaptive management, mineral cycling, southeastern wetlands, and riparian ecosystems. For the last 20 years his work has focused on responses of western riparian vegetation to flow alteration, channel modification, and herbivory. His studies have encompassed both formal models projecting likely future vegetation and long-term field studies at sites including the upper Missouri, Gunnison, upper Green, Judith, and Illinois Rivers.
- Ph.D. Ecology, University of Georgia, 1982
- B.A. Biology (Honors), Indiana University, 1973
- 2002-present, Research Ecologist, Fort Collins Science Center (Midcontinent Ecological Science Center), U.S. Geological Survey, Fort Collins, Colorado
- 2002, Supervisory Physical Scientist, Midcontinent Ecological Science Center, U.S. Geological Survey, Fort Collins, Colorado
- 1996-2001, Operations research analyst (ecological management), National Ecology Research Center, U.S. Geological Survey, Fort Collins, Colorado
- 1993-1996, Operations research analyst (ecological management), Midcontinent Ecological Science Center (National Ecology Research Center), National Biological Service (Survey), Fort Collins, Colorado
- 1984-1993, Operations research analyst (ecological management), National Ecology Research Center, U.S. Fish and Wildlife Service, Fort Collins, Colorado
- 1982-1984, Systems ecologist, Western Energy and Land Use Team, U.S. Fish and Wildlife Service (IPA appointment), Fort Collins, Colorado
- 1979-1981, Research project manager, University of Georgia, Athens, Georgia 1973-1979: Graduate assistantships, University of Georgia, Athens, Georgia
Science and Products
Formation of arroyos in the late 1800s greatly increased erosion across the southwestern United States. Since the 1930s, however, this erosion has decreased, partly because of bank stabilization by introduced saltcedar. With Isleta Pueblo Indian Nation, the Aquatic Systems Branch developed a new sediment dating method using saltcedar tree rings. We applied the method in a landmark study of...
This is a macro-embedded EXCEL program designed to easily accept input from downloaded stream gage records or output from the RIVERWARE reservoir operations model being used for the upstream Aspinall Unit.
Distribution of invasive and native riparian woody plants across the western USA in relation to climate, river flow, floodplain geometry and patterns of introduction
Management of riparian plant invasions across the landscape requires understanding the combined influence of climate, hydrology, geologic constraints and patterns of introduction. We measured abundance of nine riparian woody taxa at 456 stream gages across the western USA. We constructed conditional inference recursive binary partitioning models...Ryan McShane; Daniel Auerbach; Friedman, Jonathan M.; Auble, Gregor T.; Shafroth, Patrick B.; Michael Merigliano; Scott, Michael L.; N. Leroy Poff
Processes of arroyo filling in northern New Mexico, USA
We documented arroyo evolution at the tree, trench, and arroyo scales along the lower Rio Puerco and Chaco Wash in northern New Mexico, USA. We excavated 29 buried living woody plants and used burial signatures in their annual rings to date stratigraphy in four trenches across the arroyos. Then, we reconstructed the history of arroyo evolution by...Friedman, Jonathan M.; Vincent, Kirk R.; Griffin, Eleanor R.; Scott, Michael L.; Shafroth, Patrick B.; Auble, Gregor T.
An ecological response model for the Cache la Poudre River through Fort Collins
The Poudre River Ecological Response Model (ERM) is a collaborative effort initiated by the City of Fort Collins and a team of nine river scientists to provide the City with a tool to improve its understanding of the past, present, and likely future conditions of the Cache la Poudre River ecosystem. The overall ecosystem condition is described...Shanahan, Jennifer; Baker, Daniel; Bledsoe, Brian P.; Poff, LeRoy; Merritt, David M.; Bestgen, Kevin R.; Auble, Gregor T.; Kondratieff, Boris C.; Stokes, John; Lorie, Mark; Sanderson, John
Woody riparian vegetation near selected streamgages in the western United States
Areal cover and occupancy of woody riparian species near 456 streamgages in the western United States were obtained from site visits during the growing seasons of 1996-2002. We made concomitant estimates of grazing intensity, channel stabilization and incision, gradient, sediment particle size, and nearby planting of Russian olive. The purpose of...Auble, Gregor T.; Friedman, Jonathan M.; Shafroth, Patrick B.; Merigliano, Michael F.; Scott, Michael L.
Theory, methods and tools for determining environmental flows for riparian vegetation: Riparian vegetation-flow response guilds
Riparian vegetation composition, structure and abundance are governed to a large degree by river flow regime and flow-mediated fluvial processes. Streamflow regime exerts selective pressures on riparian vegetation, resulting in adaptations (trait syndromes) to specific flow attributes. Widespread modification of flow regimes by humans has resulted...Merritt, D.M.; Scott, M.L.; Leroy, Poff N.; Auble, G.T.; Lytle, D.A.
Decision Support System for Evaluation of Gunnison River Flow Regimes With Respect To Resources of the Black Canyon of the Gunnison National Park
This report describes and documents a decision support system for the Gunnison River in Black Canyon of the Gunnison National Park. It is a macro-embedded EXCEL program that calculates and displays indicators representing valued characteristics or processes in the Black Canyon based on daily flows of the Gunnison River. The program is designed to...Auble, Gregor T.; Wondzell, Mark; Talbert, Colin
Relation between Streamflow of Swiftcurrent Creek, Montana, and the Geometry of Passage for Bull Trout (Salvelinus confluentus)
Operation of Sherburne Dam in northcentral Montana has typically reduced winter streamflow in Swiftcurrent Creek downstream of the dam and resulted in passage limitations for bull trout (Salvelinus confluentus). We defined an empirical relation between discharge in Swiftcurrent Creek between Sherburne Dam and the downstream confluence with Boulder...Auble, Gregor T.; Holmquist-Johnson, Christopher L.; Mogen, Jim T.; Kaeding, Lynn R.; Bowen, Zachary H.
Channel Change in 2007 at Selected Sites on the Marias River, Montana, Following a 2006 High-Flow Release from Tiber Dam
In June 2006, an opportunistic high-flow release was made from Tiber Dam on the Marias River in Montana to investigate possible alternatives for partially restoring the river's natural flow pattern and variability. At two sites along the river, we measured channel geometry in 2006 before and after the high-flow release to evaluate channel change...Auble, Gregor T.; Bowen, Zachary H.
Effects of a 2006 High-Flow Release from Tiber Dam on Channel Morphology at Selected Sites on the Marias River, Montana
In June 2006, an opportunistic high-flow release was made from Tiber Dam on the Marias River in Mont., to investigate possible alternatives for partially restoring the river's natural flow pattern and variability. At two sites along the river, we measured channel geometry before and after the high-flow release to evaluate channel change and...Auble, Gregor T.; Bowen, Zachary H.
Early vegetation development on an exposed reservoir: Implications for dam removal
The 4-year drawdown of Horsetooth Reservoir, Colorado, for dam maintenance, provides a case study analog of vegetation response on sediment that might be exposed from removal of a tall dam. Early vegetation recovery on the exposed reservoir bottom was a combination of (1) vegetation colonization on bare, moist substrates typical of riparian zones...Auble, G.T.; Shafroth, P.B.; Scott, M.L.; Roelle, J.E.
Riparian willow restoration at Arapaho National Wildlife Refuge
Riparian willow communities along the Illinois River at Arapaho National Wildlife Refuge in North Park near Walden, Colorado, provide important habitat for a number of wildlife species, including neotropical migratory birds. Existing stands in the northern (downstream) portion of the refuge are sparse and discontinuous (Photo 1) compared to...Auble, G.T.; Roelle, J. E.; TImberman, A.
Transverse and longitudinal variation in woody riparian vegetation along a montane river
This study explores how the relationship between flow and riparian vegetation varies along a montane river. We mapped occurrence of woody riparian plant communities along 58 km of the San Miguel River in southwestern Colorado. We determined the recurrence interval of inundation for each plant community by combining step-backwater hydraulic...Friedman, J.M.; Auble, G.T.; Andrews, E.D.; Kittel, G.; Madole, R.F.; Griffin, E.R.; Allred, Tyler M.