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Patrick Shafroth, Ph.D.

Biography

Patrick B. Shafroth is a research ecologist with the U.S. Geological Survey, Fort Collins Science Center. Since 1991, Dr. Shafroth has conducted research on riparian ecosystems, primarily in arid and semi-arid regions of western U.S. He and his colleagues from the USGS and other institutions have focused their work on understanding relationships between surface and ground-water hydrology, fluvial processes, and the dynamics of native and introduced riparian vegetation. This research has often been conducted in the applied context of riparian ecosystem restoration with the goal of providing solid, objective scientific information that can be used to inform riparian restoration efforts. More specific restoration-related research areas include studies of large-scale flow experiments, dam removal, effects of invasive species control and associated restoration actions, and potential interactions with climate change.

Some of Dr. Shafroth’s current research includes studies of: vegetation and geomorphic responses to experimental flow releases downstream of dams on the Bill Williams River, Arizona; the Colorado River delta in Mexico and the U.S.; and the the Colorado River in Grand Canyon; vegetation and geomorphic responses to dam removal on the Elwha River, Washington, where the world's largest dam removals occurred recently; dynamics of non-native riparian plants along western rivers, including patterns of riparian vegetation recovery associated with biological control of Tamarix.

Education

  • Ph.D. in Plant Biology, Arizona State University, 1999
  • M.S. in Forest Ecology, Colorado State University, 1993
  • B.A. in Environmental Studies and Geography, University of California, Santa Barbara, 1989

Science and Products

Filter Total Items: 13
Elwha River flowing through former Aldwell reservoir
Date published: November 4, 2020
Status: Active

USGS science supporting the Elwha River Restoration Project

 

The Elwha River Restoration Project has reconnected the water, salmon, and sediment of a pristine river and coast of the Olympic Peninsula of Washington. Coordinated by the National Park Service, restoration of the Elwha River included the removal of two large dams that had blocked salmon and sediment passage for almost 100 years. The largest dam removal in U.S. history began in...

Contacts: Christopher A Curran, Jeffrey Duda, Jason B Dunham, Amy East, Guy Gelfenbaum, Kurt J Jenkins , Christopher P Konrad, Christopher Magirl, Steve Rubin, Patrick Shafroth, Ph.D., Jonathan Warrick
Attribution: Ecosystems, Natural Hazards, Coastal and Marine Hazards and Resources Program, Fisheries Program, Region 9: Columbia-Pacific Northwest, Pacific Coastal and Marine Science Center
Dead and dying cottonwoods along the Mojave River, California, following a decrease in the riparian water table
Date published: January 17, 2017
Status: Active

Ecological Drought in Riparian Ecosystems

Drought is killing riparian trees along many rivers in the western United States. The cause can be increasing temperature or decreasing precipitation, flow or water-table elevation. At multiple locations we are relating water availability to physiological measurements of tree survival and water stress, such as ring width, carbon stable isotope ratio and branch hydraulic conductivity. These...

Contacts: Jonathan Friedman, Ph.D., Patrick Shafroth, Ph.D.
Attribution: Ecosystems, Environments Program, Floods and Droughts, Region 5: Missouri Basin, Region 7: Upper Colorado Basin, Fort Collins Science Center
Invasive Tamarisk or saltcedar as it is known, growing on the side of a river.
Date published: December 3, 2016
Status: Active

Ecology and Management of Invasive Riparian Plants

Due to high rates of disturbance and human activity, streamside or “riparian” areas are prone to colonization and spread of invasive plants. In the western United States, hundreds of thousands of riparian acres are occupied by the invasive shrubs/trees tamarisk and Russian olive, as well as numerous exotic herbaceous plants. Our work focuses on understanding the factors driving the...

Contacts: Patrick Shafroth, Ph.D.
Attribution: Ecosystems, Invasive Species Program, Region 7: Upper Colorado Basin, Fort Collins Science Center
Erosion along the Rio Puerco during the flood of 2006 following herbicide application to control saltcedar in 2003.
Date published: December 3, 2016
Status: Active

Erosion and Invasive Saltcedar

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...

Contacts: Jonathan Friedman, Ph.D., Gregor Auble, Ph.D., Patrick Shafroth, Ph.D., Eleanor Griffin
Attribution: Ecosystems, Water Resources, Environments Program, Invasive Species Program, Water Availability and Use Science Program, Region 7: Upper Colorado Basin, Fort Collins Science Center
Vegetation along the Colorado River in the Grand Canyon
Date published: December 1, 2016
Status: Active

Riparian Ecology

Riparian ecologists at the Fort Collins Science Center study interactions among flow, channel change, and vegetation along rivers across the western United States and worldwide. Our work focuses on issues relevant to the management of water and public lands, including dam operation, climate change, invasive species, and ecological restoration. Investigations take place on a range of scales. ...

Contacts: Jonathan Friedman, Ph.D., Patrick Shafroth, Ph.D., Gregor Auble, Ph.D.
Attribution: Ecosystems, Environments Program, Floods and Droughts, Invasive Species Program, Region 5: Missouri Basin, Region 6: Arkansas-Rio Grande-Texas-Gulf, Region 7: Upper Colorado Basin, Region 9: Columbia-Pacific Northwest, Region 11: Alaska, Fort Collins Science Center
Glines Canyon Dam on the Elwha River, during the dam removal process. Photo credit: National Park Service
Date published: November 29, 2016
Status: Archived

Riparian Vegetation Response to Dam Removal

Dam removal is an approach to river restoration that is becoming increasingly common. In most cases, dam removal is driven by considerations other than river restoration like dam safety, but how dam removal affects aquatic and riparian systems is of great interest in many dam removals. My work in this area has had two areas of focus thus far: 1) studies of vegetation and geomorphic change...

Contacts: Patrick Shafroth, Ph.D.
Attribution: Ecosystems, Coastal and Marine Hazards and Resources Program, Environments Program, Region 7: Upper Colorado Basin, Region 9: Columbia-Pacific Northwest, Fort Collins Science Center
The South Platte River. USGS Water Science Center image.
Date published: November 29, 2016
Status: Active

Science to Inform Riparian Ecosystem Restoration and Management

Throughout the world, riparian habitats have been dramatically modified from their natural condition. Dams, non-native species and climate change are often principal drivers of these changes, via their alteration of water and sediment regimes that determine key resources for riparian plants.

Contacts: Patrick Shafroth, Ph.D.
Attribution: Ecosystems, Environments Program, Invasive Species Program, Region 7: Upper Colorado Basin, Fort Collins Science Center
The Bill Williams River in Arizona. USGS photo.
Date published: November 29, 2016
Status: Active

Large-scale streamflow experiments

Because the underlying cause of riparian system alteration is often attributed to the effects of dams on flow regime, managing flow releases, particularly high flows, from dams is an often-advocated approach to river and riparian restoration. Our work has focused on understanding effects of managed high flow releases (a.k.a., pulse flows, controlled floods) from dams along rivers in the lower...

Contacts: Patrick Shafroth, Ph.D.
Attribution: Ecosystems, Environments Program, Invasive Species Program, Fort Collins Science Center
Extensive defoliation of tamarisk (orange/brown vegetation throughout mid-ground) along the Virgin River, Arizona, 2009.
Date published: November 28, 2016
Status: Active

Biological Invasions of Riparian Ecosystems

Beginning in the early twentieth century, non-native trees and shrubs, including tamarisk (also commonly known as saltcedar) and Russian-olive, were introduced to the United States for use as ornamental plants and in erosion-control plantings. These plants spread extensively, becoming the third and fourth most frequently occurring woody riparian plants in the American West.

 

Contacts: Patrick Shafroth, Ph.D.
Attribution: Ecosystems, Environments Program, Invasive Species Program, Region 7: Upper Colorado Basin, Fort Collins Science Center
The unregulated Santa Maria River in west-central Arizona.
Date published: November 28, 2016
Status: Active

Streamflow-fluvial Geomorphology-riparian Vegetation Interactions

The foundation for applying science to river and riparian restoration contexts lies in a basic understanding of the factors that drive riparian vegetation dynamics. Much of our research is focused on clarifying relationships between streamflow, fluvial geomorphology, and riparian vegetation, including various feedbacks.

Contacts: Patrick Shafroth, Ph.D.
Attribution: Ecosystems, Environments Program, Invasive Species Program, Region 7: Upper Colorado Basin, Region 9: Columbia-Pacific Northwest, Fort Collins Science Center
Image: Elwha River Restoration
Date published: August 29, 2016
Status: Active

Ecological Flows

Ecological flow is a central theme of AS Branch studies, as our research examines how water flows affect populations, communities, ecosystems, and hydroscapes. Our studies elucidate the interactions among hydrologic, geomorphologic, biogeochemical, biological, and anthropogenic processes. Branch scientists identify and quantify the spatial and temporal attributes of water flow for ecological...

Contacts: Jonathan Friedman, Ph.D., Patrick Shafroth, Ph.D.
Attribution: Fort Collins Science Center
USGS science for a changing world logo
Date published: October 25, 2013
Status: Active

Dam removal: synthesis of ecological and physical responses

Dam decommissioning is rapidly emerging as an important river restoration strategy in the U.S., with several major removals recently completed or in progress. But few studies have evaluated the far-reaching consequences of these significant environmental perturbations, especially those resulting from removals of large (>10-15 m tall) structures during the last decade. In particular,...

Contacts: Jim E O'Connor, Jeffrey Duda, Amy East, Chauncey Anderson, Patrick Connolly, Ph.D., Jonathan Warrick, Jon Major, Patrick Shafroth, Ph.D., Melissa Foley, Christopher Magirl
Attribution: John Wesley Powell Center for Analysis and Synthesis
Filter Total Items: 113
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Year Published: 2021

Riverine complexity and life history inform restoration in riparian environments in the southwestern U.S.

Riparian habitat in the southwestern USA has undergone substantial degradation over the past century, prompting extensive management and restoration of these critical ecosystems. Most restoration efforts, however, do not account for life history traits or riverine complexity that may influence genetic diversity and structure. Here, we use simple...

Palmquist, Emily C.; Allan, Gerald J; Ogle, Kiona; Whitham, Thomas G.; Butterfield, Bradley J.; Shafroth, Patrick B.

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Year Published: 2021

The Transformation of dryland rivers: The future of introduced tamarisk in the U.S.

Tamarix spp. (tamarisk or saltcedar), a shrub-like tree, was intentionally introduced to the U.S. from Asia in the mid-1800s. Tamarisk thrives in today’s human-altered streamside (riparian) habitats and can be found along wetlands, rivers, lakes, and streams across the western U.S. In 2001, a biological control agent, Diorhabda spp. (tamarisk leaf...

Nagler, Pamela L.; Hull, Julia B.; van Riper, Charles; Shafroth, Patrick B.; Yackulic, Charles B.
View Citation
Nagler, P.L., Hull, J.B., van Riper, C., Shafroth, P.B., and Yackulic, C.B., 2021, The Transformation of dryland rivers: The future of introduced tamarisk in the U.S.: U.S. Geological Survey Fact Sheet 2020–3061, 6 p., https://doi.org/10.3133/fs20203061.

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Year Published: 2021

Quantifying and securing environmental flow

No abstract available.

McCoy, Amy; Shafroth, Patrick B.; Briggs, Mark; Schlatter, Karen; White, Lindsay; Zamora, Francisco; de la Maza Benignos, Mauricio; Pitt, Jennifer; Tashjian, Paul; Carrillo, Yamilette

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Year Published: 2021

Stream-corridor restoration: Some assembly required

No abstract available.

Briggs, Mark K.; Gonzalez, Eduardo; Osterkamp, Waite R.; Shafroth, Patrick B.; Zamora, Francisco

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Year Published: 2021

A case for stream corridor restoration

No abstract available.

Briggs, Mark K.; Hinojosa-Huerta, Osvel; Osterkamp, Waite R.; Shafroth, Patrick B.; Sifuentes Lugo, Carlos A.; White, Lindsay; Zamora, Francisco

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Year Published: 2020

Ecological interfaces between land and flowing water: Themes and trends in riparian research and management

This paper provides an overview of past, present and future themes for research and management of riparian zones, often relating to papers within this Wetlands Special Feature. Riparian research expanded in the United States around 1980 with themes that recognized (1) damage from excessive livestock, or (2) damage from river damming and...

Rood, Stewart B.; Scott, Michael L; Dixon, Mark; Gonzalez, Eduardo; Marks, Christian O; Shafroth, Patrick B.; Volk, Martin

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Year Published: 2020

Riparian plant communities remain stable in response to a second cycle of Tamarix biocontrol defoliation

Reduced abundance of non-native Tamarix shrubs in western U.S. riparian systems following biological control by a defoliating beetle has led to concerns that replacement plant communities could be dominated by other invasive species and/or not provide some of the ecosystem services that Tamarix was providing. In previous...

Eduardo Gonzalez; Shafroth, Patrick B.; Lee, Steven R.; Reed, Sasha; Belnap, Jayne

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Year Published: 2020

Flow‐ecology modelling to inform reservoir releases for riparian restoration and management

Linked hydrologic, hydraulic, and ecological models can facilitate planning and implementing water releases from reservoirs to achieve ecological objectives along rivers. We applied a flow‐ecology model, the Ecosystem Functions Model (HEC‐EFM), to the Bill Williams River in southwestern USA to estimate areas suitable for recruitment of riparian...

Hickey, John T; Shafroth, Patrick B.; Fields, Woodrow L

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Year Published: 2020

Combined effects of biological control of an invasive shrub and fluvial processes on riparian vegetation dynamics

Plant community responses to biocontrol of invasive plants are understudied, despite the strong influence of the composition of replacement vegetation on ecosystem functions and services. We studied the vegetation response to a folivore beetle (Diorhabda genus, Coleoptera) that has been introduced along southwestern US river valleys to...

Gonzalez, Eduardo; Shafroth, Patrick B.; Lee, Steven R.; Ostoja, Steven M.; Brooks, Matthew L.

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Year Published: 2020

Effect of an environmental flow on vegetation growth and health using ground and remote sensing metrics

Understanding the effectiveness of environmental flow deliveries along rivers requires monitoring vegetation. Monitoring data are often collected at multiple spatial scales. For riparian vegetation, optical remote sensing methods can estimate growth responses at the riparian corridor scale, and field‐based measures can quantify species composition...

Gomez-Sapiens, Martha M.; Jarchow, Christopher; Flessa, Karl W.; Shafroth, Patrick B.; Glenn, Edward P.; Nagler, Pamela L.

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Year Published: 2019

Short-term geomorphological and riparian vegetation responses to a 40-year flood on a braided, dryland river

In December 2010, a 40-yr flood occurred in the lower Virgin River (SE Nevada, southwestern U.S.), a braided river segment with riparian vegetation largely dominated by invasive shrubs in the genus Tamarix. We assessed geomorphological and vegetation responses to this large magnitude disturbance event by comparing pre- and post-flood remote...

Gozalez, Eduardo; Shafroth, Patrick B.; Lee, Steven R.; Leverich, Glen T.; Real de Asua, Rafael; Sherry, Rebecca A.; Ostoja, Steven M.; Orr, Bruce K.

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Year Published: 2019

Projected warming disrupts the synchrony of riparian seed dispersal and snowmelt streamflow

• Globally, spring phenology and abiotic processes are shifting earlier with warming. Differences in the magnitudes of these shifts may decouple the timing of plant resource requirements from resource availability. In riparian forests across the northern hemisphere, warming could decouple seed dispersal from snowmelt peak streamflow, thus reducing...

Perry, Laura G.; Shafroth, Patrick B.; Hay, Lauren; Markstrom, Steven L.; Bock, Andrew R.

Pre-USGS Publications

Ground-water recharge and riparian habitat enhancement from water discharged from New Waddell Dam into the Agua Fria River: Phase I--Planning and feasibility
Shafroth, P.B., J.C. Stromberg, D.T. Patten, A.E. Springer, and J.M. Wright. 1996. Ground-water recharge and riparian habitat enhancement from water discharged from New Waddell Dam into the Agua Fria River: Phase I--Planning and feasibility. Final Report to Arizona Dept. of Water Resources - Phoenix Active Management Area. Phoenix, AZ78+ap p.
River salinity has little influence on establishment of cottonwood and saltcedar. Research Information Bulletin 94-95
Shafroth, P.B., J.M. Friedman, and L.S. Ischinger. 1994. River salinity has little influence on establishment of cottonwood and saltcedar. Research Information Bulletin 94-95. NBS Information Bulletin.