Cameron L Aldridge, PhD
Dr. Cameron Aldridge is a research ecologist at the Fort Collins Science Center. Dr. Aldridge's work focuses on the conservation and management of sage-grouse and their habitats.
Dr. Cameron Aldridge is a Research Ecologist with the US Geological Survey, based at the Fort Collins Science Center, who works in collaboration with the Natural Resource Ecology Lab at Colorado State University. He is also an Affiliate Research Scientist at NREL and an Affiliate Professor with ESS and GDPE.
His research is diverse, but he is best recognized as one of the foremost sage-grouse ecologists in the world. He has a large research program focused on understanding the conservation and management of Greater and Gunnison Sage-grouse and their habitats. His research team includes both undergraduate and graduate students, research associates, post-doctoral fellows, and research scientists, all of which collaborate to understand why sage-grouse populations have declined, what major factors affect resource conditions and quality for sage-grouse, what drives population dynamics. The Aldridge Lab works closely on these issues with state and federal partners, as well as NGOs, conservation groups and industry.
More broadly, research in the Aldridge Lab involves understanding animal-habitat relationships, with an emphasis on conservation ecology and population demography. Researchers in the lab are addressing the effects of energy development, land-use change, and climate change on conserving wildlife populations, their habitats, and the ecosystems they inhabit. Species that we are currently studying include songbirds and small mammals, snakes and lizards, and grouse, such as white-tailed ptarmigan and sage-grouse. We also work with plant communities and exotic invasive plants, understanding how external drivers such as climate, grazing and energy development affect plant communities. We work across spatial scales, and use statistical and empirical modeling to answer these research and conservation questions, most of which have direct applications for conservation and management of the species and their habitats. Most of the research has direct applications for conservation and management of the species, most notably sage-grouse, and their habitats.
Professional Experience
August 2023-Present Branch Chief, and Research Supervisory Ecologist, Ecosystem and Landscape Dynamic Research Branch, US Geological Survey, Fort Collins Science Center, Fort Collins, Colorado.
March 2022-Present Acting Branch Chief, Ecosystem and Landscape Dynamic Research Branch, US Geological Survey, Fort Collins Science Center, Fort Collins, Colorado
Feb. 2020-Present Research Ecologist, US Geological Survey, Fort Collins Science Center, Fort Collins, Colorado
Feb. 2020-Present Affiliate Research Scientist, Natural Resource Ecology Laboratory, Colorado State University
Feb. 2020-Present Affiliate Professor, Department of Ecosystem Science and Sustainability and Graduate Degree Program in Ecology, Colorado State University
Jan. 2017-20 Finance Committee Member for the Natural Resource Ecology Laboratory, Colorado State University
July 2015-20 Associate Professor with Tenure, Department of Ecosystem Science and Sustainability, Colorado State University
July 2015-Present Research Scientist III, Natural Resource Ecology Laboratory, Colorado State University & U.S. Geological Survey, FORT Science Center, Fort Collins, Colorado
Aug. 2014-16 Executive Committee Member, Graduate Degree Program in Ecology, Colorado State University
Jan. 2012-18 Graduate Program Advisor for the Department of Ecosystem Science and Sustainability, Natural Resource Ecology Laboratory, Colorado State University.
Aug. 2010 Assistant Professor, Department of Ecosystem Science and Sustainability, Colorado State University.
July 2009 Research Scientist II, Natural Resource Ecology Laboratory, Colorado State University & U.S. Geological Survey, FORT Science Center, Fort Collins, Colorado.
Feb. 2007-Present Faculty Member, Graduate Degree Program in Ecology (GDPE), Colorado State University
Feb. 2007-11 Joint Faculty Member, Department of Fish, Wildlife, and Conservation Biology, Colorado State University
Oct. 2006 Research Scientist, Natural Resource Ecology Laboratory, Colorado State University & U.S. Geological Survey, FORT Science Center, Fort Collins, Colorado.
Education and Certifications
2005 - 2006 Post Doctoral Research Fellow, Natural Resource Ecology Laboratory, Colorado State University & U.S. Geological Survey, FORT Science Center, Fort Collins, CO.
2000 - 2005 Doctorate of Philosophy in Ecology, Department of Biological Sciences, University of Alberta, Edmonton, Alberta.
1998 - 2000 Master of Science in Biology, Department of Biology, University of Regina, Regina, Saskatchewan.
1991 - 1996 Bachelor of Science double major in Ecology and Zoology, Department of Biological Sciences, University of Calgary, Calgary, Alberta.
Science and Products
Fuel Break Science in the Great Basin
Linking post-fire sagebrush restoration and sage-grouse habitat recovery
Changes in Sagebrush Ecosystem Connectivity
Economic assessment of addressing annual invasive grasses across the sagebrush biome
Data Harmonization for Greater Sage-Grouse Populations
Modeling Songbird Density-Habitat Relationships to Predict Population Responses to Environmental Change Within Pinyon-juniper and Sagebrush Ecosystems
Hierarchical Units of Greater Sage-Grouse Populations Informing Wildlife Management
Mapping Grassland Bird Community Distribution under a Changing Climate
What Will Grassland Bird Communities Look Like Under a Changing Climate?
Prioritizing Restoration of Sagebrush Ecosystems Tool (PReSET): A USGS-facilitated Decision-support Tool for Sagebrush Ecosystem Conservation and Restoration Actions
Invasive Annual Grass (IAG) Spatial Dataset Compilation and Synthesis
Optimization of Management Actions for Restoration Success and Wildlife Populations
Predicted (1989-2015) and forecasted (2015-2114) estimates for rate of change and recovery of sagebrush (Artemisia spp.) following energy development in southwestern Wyoming, USA (ver. 2.0, January 2021)
Sample collection information and SNP data for Gunnison Sage-grouse across the species range generated in the Molecular Ecology Lab during 2015-2018
Sample collection information and microsatellite data for Gunnison sage-grouse pre and post translocation
Influences of Potential Oil and Gas Development and Future Climate on Sage-Grouse Declines and Redistribution
Sample collection information, single nucleotide polymorphism, and microsatellite data for white-tailed ptarmigan across the species range generated in the Molecular Ecology Lab during 2016
Predicted (1989-2015) and forecasted (2015-2114) estimates for rate of change and recovery of sagebrush (Artemisia spp.) following energy development in southwestern Wyoming, USA
Hierarchically nested and biologically relevant monitoring frameworks for Greater Sage-grouse, 2019, Nevada and Wyoming, Interim
Simulation to evaluate response of population models to annual trends in detectability
Compendium to invasive annual grass spatial products for the western United States, January 2010-February 2021
A user guide to selecting invasive annual grass spatial products for the western United States
Assessing vegetation recovery from energy development using a dynamic reference approach
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report
Prioritizing restoration areas to conserve multiple sagebrush-associated wildlife species
Integrating wildlife habitat models with state-and-transitions models to enhance the management of rangelands for multiple objectives
Synthesizing and analyzing long-term monitoring data: A greater sage-grouse case study
Range-wide greater sage-grouse hierarchical monitoring framework—Implications for defining population boundaries, trend estimation, and a targeted annual warning system
Prioritizing landscapes for grassland bird conservation with hierarchical community models
Using remote sensing products to predict recovery of vegetation across space and time following energy development
Environmental gradients of selection for an alpine-obligate bird, the white-tailed ptarmigan (Lagopus leucura)
Postfire growth of seeded and planted big sagebrush - Strategic designs for restoring Greater Sage-grouse nesting habitat
Science and Products
- Science
Filter Total Items: 58
Fuel Break Science in the Great Basin
Researchers from the U.S. Geological Survey are developing a strategic framework for assessing and monitoring the impacts of fuel breaks in sagebrush ecosystems of the western U.S. Fuel breaks are increasingly being used to reduce the threat of wildfire, but more information on their efficacy and impacts on wildlife habitat and exotic annual grass invasion is needed.Linking post-fire sagebrush restoration and sage-grouse habitat recovery
Many revegetation projects are intended to benefit focal wildlife species. Yet, few scope the ability of revegetation efforts to yield habitat. To investigate the ability of alternative sagebrush ( Artemisia species) planting strategies to recover habitat conditions for the greater sage-grouse ( Centrocercus urophasianus ), USGS and Colorado State University scientists developed a spatial...Changes in Sagebrush Ecosystem Connectivity
Disturbances, management, and changing environmental conditions have reshaped the sagebrush biome within the western United States. As a result, sagebrush cover and configuration have varied over space and time, influencing ecological processes and species' use of the landscape. Characterizing changes in sagebrush ecosystem connectivity over time will help us understand the effects of those...Economic assessment of addressing annual invasive grasses across the sagebrush biome
This interdisciplinary project combines expert judgment on treatment costs with spatially explicit ecological modeling to estimate the financial resources needed to address the threat of invasive annual grass across the entire sagebrush biome. Results of the assessment will provide economic insights that can inform cost-effective resource allocation to efficiently achieve sagebrush conservation...Data Harmonization for Greater Sage-Grouse Populations
Long-term wildlife monitoring is imperative for understanding population changes that can inform managers. However, working with population data collected by different organizations, across multiple jurisdictions, and over long time periods can be challenging due to different data management approaches and organizational priorities. Through this project, we aimed to collaborate with eleven state...Modeling Songbird Density-Habitat Relationships to Predict Population Responses to Environmental Change Within Pinyon-juniper and Sagebrush Ecosystems
Within areas of overlapping sagebrush and pinyon-juniper ecosystems, wildlife populations are declining due to habitat fragmentation and degradation, changing climate, and human development. However, management to bolster species associated with one ecosystem may result in negative consequences for species associated with the other. Thus, land managers are challenged with balancing which system to...Hierarchical Units of Greater Sage-Grouse Populations Informing Wildlife Management
Wildlife management boundaries frequently lack biological context, such as information on habitat resource availability and wildlife movements. To address this, we developed multiple levels of biologically relevant and hierarchically nested greater sage-grouse ( Centrocercus urophasianus ) population units that could facilitate management and conservation of populations and habitats.Mapping Grassland Bird Community Distribution under a Changing Climate
Researchers from the U.S. Geological Survey, the U.S. Department of Agriculture-Agricultural Research Service, and Oklahoma State University are studying the distribution of grassland bird communities across the western Great Plains to anticipate how species distributions may respond to a changing climate.What Will Grassland Bird Communities Look Like Under a Changing Climate?
Over the last half-century, grassland bird populations have declined far more than any other bird group in North America. This is because native grasslands were largely replaced with croplands, and many remaining prairies are degraded. Land managers and conservation organizations are racing to preserve and restore these ecosystems to stem further loss of grassland birds. Given limited resources, bPrioritizing Restoration of Sagebrush Ecosystems Tool (PReSET): A USGS-facilitated Decision-support Tool for Sagebrush Ecosystem Conservation and Restoration Actions
Sagebrush ecosystems represent one of the most imperiled systems in North America and face continued and widespread degradation due to multiple factors including climate change, invasive species, and increased human development. Effective sagebrush management must consider how to best conserve and restore habitats to stem the decline of species that rely on them, especially given limited...Invasive Annual Grass (IAG) Spatial Dataset Compilation and Synthesis
USGS is working closely with partners in the Bureau of Land Management (BLM), U.S. Fish and Wildlife Service (USFWS), and the Intermountain West Joint Venture (IMJV) to collect and summarize spatial datasets that describe measurable aspects of invasive annual grasses (e.g., biomass or presence) across the western United Stated and beyond. The products developed through this project provide...Optimization of Management Actions for Restoration Success and Wildlife Populations
USGS researchers, in collaboration with the Wyoming Landscape Conservation Initiative and other partners, are developing a statistically based prioritization tool that will aid agencies in their management decisions. - Data
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Predicted (1989-2015) and forecasted (2015-2114) estimates for rate of change and recovery of sagebrush (Artemisia spp.) following energy development in southwestern Wyoming, USA (ver. 2.0, January 2021)
In 'Predicted (1989-2015) and forecasted (2015-2114) rate of change and recovery of sagebrush (Artemisia spp.) following energy development in southwestern Wyoming, USA (ver. 2.0, January 2021)', we provide spatially- and temporally-explicit maps of predictions for the rate of change and time to recovery and percent recovery of sagebrush cover after 100 years (Monroe et al. 2020). The rasters begiSample collection information and SNP data for Gunnison Sage-grouse across the species range generated in the Molecular Ecology Lab during 2015-2018
This dataset contains sample collection information and SNP genotypes for populations of Gunnison Sage-grouse across the species' range. This data was collected in order to examine patterns of adaptive genetic variation in Gunnison Sage-grouse. The data is archived in GenBank at the following URL https://www.ncbi.nlm.nih.gov/bioproject/517770.Sample collection information and microsatellite data for Gunnison sage-grouse pre and post translocation
Maintenance of genetic diversity is important for conserving species, especially those with fragmented habitats and/or ranges. In the absence of natural dispersal, translocation can be used to achieve this goal. However, the long-term impacts from translocation can be expensive and difficult to evaluate. This dataset is used to evaluate genetic change as a result of translocation and represents saInfluences of Potential Oil and Gas Development and Future Climate on Sage-Grouse Declines and Redistribution
This project represents the data used in "Influences of potential oil and gas development and future climate on sage-grouse declines and redistribution." The data sets describe greater sage-grouse (Centrocercus urophasianus) population change, summarized in different boundaries within the Wyoming Landscape Conservation Initiative (WLCI; southwestern Wyoming). Population changes were based on diffSample collection information, single nucleotide polymorphism, and microsatellite data for white-tailed ptarmigan across the species range generated in the Molecular Ecology Lab during 2016
This data release comprises a dataset that contains sample collection information and microsatellite genotypes, and another dataset that contains single nucleotide polymorphism (SNP) genotypes with sample collection information for populations of white-tailed ptarmigan across the species' range. There is also an additional file (accession numbers.xlsx) linking samples to accession numbers in GenbaPredicted (1989-2015) and forecasted (2015-2114) estimates for rate of change and recovery of sagebrush (Artemisia spp.) following energy development in southwestern Wyoming, USA
In 'Predicted (1989-2015) and forecasted (2015-2114) estimates for rate of change and recovery of sagebrush (Artemisia spp.) following energy development in southwestern Wyoming, USA', we provide spatially- and temporally-explicit maps of predictions for the rate of change and time to recovery and percent recovery of sagebrush cover after 100 years (Monroe et al. In Review). The rasters beginningHierarchically nested and biologically relevant monitoring frameworks for Greater Sage-grouse, 2019, Nevada and Wyoming, Interim
We developed a hierarchical clustering approach that identifies biologically relevant landscape units that can 1) be used as a long-term population monitoring framework, 2) be repeated across the Greater sage-grouse range, 3) be used to track the outcomes of local and regional populations by comparing population changes across scales, and 4) be used to inform where to best spatially target studiesSimulation to evaluate response of population models to annual trends in detectability
In 'Simulation to evaluate response of population models to annual trends in detectability', we provide data and R code necessary to create simulation scenarios and estimate trends with different population models (Monroe et al. 2019). Literature cited: Monroe, A. P., G. T. Wann, C. L. Aldridge, and P. S. Coates. 2019. The importance of simulation assumptions when evaluating detectability in p - Multimedia
- Publications
Filter Total Items: 120
Compendium to invasive annual grass spatial products for the western United States, January 2010-February 2021
Invasive annual grasses (IAGs) degrade native plant communities, alter fire cycles, impact ecosystem processes, and threaten the persistence of some species. Therefore, controlling the spread of IAGs has become a land management priority in the western United States. A wide array of geospatial data has been developed in the last decade to help land managers combat the invasion and expansion of nonAuthorsD. Joanne Saher, Jessica E. Shyvers, Bryan C. Tarbox, Nathan D. Van Schmidt, Julie A. Heinrichs, Cameron L. AldridgeA user guide to selecting invasive annual grass spatial products for the western United States
Invasive annual grasses (IAGs)—including Bromus tectorum (cheatgrass), Taeniatherum caput-medusae (medusahead), and Ventenata dubia (ventenata) species—present significant challenges for rangeland management by altering plant communities, impacting ecosystem function, reducing forage for wildlife and livestock, and increasing fire risk. Numerous spatial data products are used to map IAGs, and undeAuthorsNathan D. Van Schmidt, Jessica E. Shyvers, D. Joanne Saher, Bryan C. Tarbox, Julie A. Heinrichs, Cameron L. AldridgeAssessing vegetation recovery from energy development using a dynamic reference approach
Ecologically relevant references are useful for evaluating ecosystem recovery, but references that are temporally static may be less useful when environmental conditions and disturbances are spatially and temporally heterogeneous. This challenge is particularly acute for ecosystems dominated by sagebrush (Artemisia spp.), where communities may require decades to recover from disturbance. We demonsAuthorsAdrian P. Monroe, Travis W. Nauman, Cameron L. Aldridge, Michael O'Donnell, Michael C. Duniway, Brian S. Cade, Daniel Manier, Patrick J. AndersonU.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report
The Wyoming Landscape Conservation Initiative (WLCI) was established in 2007 as a collaborative interagency partnership to develop and implement science-based conservation actions. During the past 11 years, partners from U.S. Geological Survey (USGS), State and Federal land management agencies, universities, and the public have collaborated to implement a long-term (more than 10 years) science-basAuthorsPatrick J. Anderson, Cameron L. Aldridge, Jason S. Alexander, Timothy J. Assal, Steven Aulenbach, Zachary H. Bowen, Anna D. Chalfoun, Geneva W. Chong, Holly Copeland, David R. Edmunds, Steve Germaine, Tabitha Graves, Julie A. Heinrichs, Collin G. Homer, Christopher Huber, Aaron N. Johnston, Matthew J. Kauffman, Daniel J. Manier, Ryan R. McShane, Cheryl A. Eddy-Miller, Kirk A. Miller, Adrian P. Monroe, Michael S. O'Donnell, Anna Ortega, Annika W. Walters, Daniel J. Wieferich, Teal B. Wyckoff, Linda ZeigenfussPrioritizing restoration areas to conserve multiple sagebrush-associated wildlife species
Strategic restoration of altered habitat is one method for addressing worldwide biodiversity declines. Within the sagebrush steppe of western North America, habitat degradation has been linked to declines in many species, making restoration a priority for managers; however, limited funding, spatiotemporal variation in restoration success, and the need to manage for diverse wildlife species make deAuthorsCourtney Jean Duchardt, Adrian P. Monroe, Julie A. Heinrichs, Michael O'Donnell, David R. Edmunds, Cameron L. AldridgeIntegrating wildlife habitat models with state-and-transitions models to enhance the management of rangelands for multiple objectives
State-and-transition models (STMs) are tools used in rangeland management to describe linear and nonlinear vegetation dynamics as conceptual models. STMs can be improved by including additional ecosystem services, such as wildlife habitat, so that managers can predict how local populations might respond to state changes and to illustrate the tradeoffs in managing for different ecosystem services.AuthorsJennifer M. Timmer, Crystal Y. Tipton, Retta A. Bruegger, David J. Augustine, Christopher P.K. Dickey, Maria E. Fernandez-Gimenez, Cameron L. AldridgeSynthesizing and analyzing long-term monitoring data: A greater sage-grouse case study
Long-term monitoring of natural resources is imperative for increasing the understanding of ecosystem processes, services, and how to manage those ecosystems to maintain or improve function. Challenges with using these data may occur because methods of monitoring changed over time, multiple organizations collect and manage data differently, and monetary resources fluctuate, affecting many aspectsAuthorsMichael O'Donnell, David R. Edmunds, Cameron L. Aldridge, Julie A. Heinrichs, Adrian P. Monroe, Peter S. Coates, Brian G. Prochazka, Thomas J Christiansen, Steve E. Hanser, Lief A. Wiechman, Avery A Cook, Shawn P. Espinosa, Lee J. Foster, Kathleen A. Griffin, Jesse L. Kolar, Katherine Miller, Ann M. Moser, Thomas E. Remington, Travis J Runia, Leslie A Schreiber, Michael A Schroeder, San J Stiver, Nyssa I Whitford, Catherine S WightmanRange-wide greater sage-grouse hierarchical monitoring framework—Implications for defining population boundaries, trend estimation, and a targeted annual warning system
Incorporating spatial and temporal scales into greater sage-grouse (Centrocercus urophasianus) population monitoring strategies is challenging and rarely implemented. Sage-grouse populations experience fluctuations in abundance that lead to temporal oscillations, making trend estimation difficult. Accounting for stochasticity is critical to reliably estimate population trends and investigate variaAuthorsPeter S. Coates, Brian G. Prochazka, Michael S. O'Donnell, Cameron L. Aldridge, David R. Edmunds, Adrian P. Monroe, Mark A. Ricca, Gregory T. Wann, Steve E. Hanser, Lief A. Wiechman, Michael P. ChenaillePrioritizing landscapes for grassland bird conservation with hierarchical community models
ContextGiven widespread population declines of birds breeding in North American grasslands, management that sustains wildlife while supporting rancher livelihoods is needed. However, management effects vary across landscapes, and identifying areas with the greatest potential bird response to conservation is a pressing research need.ObjectivesWe developed a hierarchical modeling approach to study gAuthorsAdrian Pierre-Frederic Monroe, David R. Edmunds, Cameron L. Aldridge, Matthew J Holloran, Timothy J Assal, Alison G HolloranUsing remote sensing products to predict recovery of vegetation across space and time following energy development
Using localized studies to understand how ecosystems recover can create uncertainty in recovery predictions across landscapes. Large archives of remote sensing data offer opportunities for quantifying the spatial and temporal factors influencing recovery at broad scales and predicting recovery. For example, energy production is a widespread and expanding land use among many semi-arid ecosystems ofAuthorsAdrian P. Monroe, Cameron L. Aldridge, Michael O'Donnell, Daniel Manier, Collin Homer, Patrick J. AndersonEnvironmental gradients of selection for an alpine-obligate bird, the white-tailed ptarmigan (Lagopus leucura)
The warming climate will expose alpine species adapted to a highly seasonal, harsh environment to novel environmental conditions. A species can shift their distribution, acclimate, or adapt in response to a new climate. Alpine species have little suitable habitat to shift their distribution, and the limits of acclimation will likely be tested by climate change in the long-term. Adaptive genetic vaAuthorsShawna J Zimmerman, Cameron L. Aldridge, Kathryn M. Langin, Gregory T Wann, Robert S. Cornman, Sara J. Oyler-McCancePostfire growth of seeded and planted big sagebrush - Strategic designs for restoring Greater Sage-grouse nesting habitat
Wildfires change plant community structure and impact wildlife habitat and population dynamics. Recent wildfire‐induced losses of big sagebrush (Artemisia tridentata) in North American shrublands are outpacing natural recovery and leading to substantial losses in habitat for sagebrush‐obligate species such as Greater Sage‐grouse. Managers are considering restoration strategies that include plantinAuthorsDavid A. Pyke, Robert K. Shriver, Robert Arkle, David Pilliod, Cameron L. Aldridge, Peter S. Coates, Matthew Germino, Julie A. Heinrichs, Mark A. Ricca, Scott Shaff - Software
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