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: 12

Location

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 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

Date published: January 17, 2017

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

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., Robert Reed, Ph.D.

Attribution: Ecosystems, Invasive Species Program, Region 7: Upper Colorado Basin, Fort Collins Science Center

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

Date published: December 1, 2016

Status: Active

Riparian Ecology

Riparian ecologists in the AS Branch 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. For example,...

Contacts: Gregor Auble, Ph.D., Jonathan Friedman, Ph.D., Patrick Shafroth, Ph.D., Quan Dong, Ph.D.

Attribution: Ecosystems, Environments Program, Floods and Droughts, Invasive Species Program, Region 11: Alaska, Region 5: Missouri Basin, Region 6: Arkansas-Rio Grande-Texas-Gulf, Region 9: Columbia-Pacific Northwest, Region 7: Upper Colorado Basin, Fort Collins Science Center

Date published: November 29, 2016

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 9: Columbia-Pacific Northwest, Region 7: Upper Colorado Basin, Fort Collins Science Center

Date published: November 29, 2016

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

Date published: November 29, 2016

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

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

Date published: November 28, 2016

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 9: Columbia-Pacific Northwest, Region 7: Upper Colorado Basin, Fort Collins Science Center

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

Date published: January 1, 2012

Status: Completed

Projecting Future Climate Effects on Cottonwood and Willow Seed Dispersal and Tree Regeneration in Western Riparian Forests

Throughout western North America, warming associated with climate change is leading to both earlier spring peak streamflows and earlier seed dispersal, potentially reducing seedling establishment and in turn reducing the quality of riparian (near-river) forests, which provide critical habitat for diverse birds, mammals, reptiles, amphibians, and insects, and food and shade for fish and other...

Contacts: Patrick Shafroth, Ph.D.

Attribution: Climate Adaptation Science Centers

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.

Patrick Shafroth, Ph.D.

Biography

USGS science supporting the Elwha River Restoration Project

Ecological Drought in Riparian Ecosystems

Ecology and Management of Invasive Riparian Plants

Erosion and Invasive Saltcedar

Riparian Ecology

Riparian Vegetation Response to Dam Removal

Science to Inform Riparian Ecosystem Restoration and Management

Large-scale streamflow experiments

Biological Invasions of Riparian Ecosystems

Streamflow-fluvial Geomorphology-riparian Vegetation Interactions

Dam removal: synthesis of ecological and physical responses

Projecting Future Climate Effects on Cottonwood and Willow Seed Dispersal and Tree Regeneration in Western Riparian Forests

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

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

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

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

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

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

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

Conceptualizing ecological responses to dam removal: If you remove it, what's to come?

Vegetative and geomorphic complexity at tributary junctions on the Colorado and Dolores Rivers: a blueprint for riparian restoration

The role of a non-native tree in riparian vegetation expansion and channel narrowing along a dryland river

Regeneration of Salicaceae riparian forests in the Northern Hemisphere: A new framework and management tool

Divergent effects of land-use, propagule pressure, and climate on woody riparian invasion

Pre-USGS Publications