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Ecosystem Dynamics


and is responsible for managing and monitoring these ever-growing 

herds. To help the BLM achieve greater science-based management, 

FORT scientists coordinated expert input on five key management 

topics—fertility control, genetic conservation, population dynamics, 

habitat assessments, and health and handling concerns—and developed a long-range strategic research plan for the BLM, incorporating BLM management goals for these animals. FORT scientists 

are also developing and testing more accurate population estimate 

techniques. 

Riparian Ecology 

Riparian ecosystems in the arid West support large and diverse 

communities of plants and animals, improve water quality, attenuate 

floods, and provide recreational opportunities. However, the 

Capabilities 

ation of a web of interactions among ecosystem components. The spatial 

that are useful for management and planning. 

Selected Projects 

Herbivore-Ecosystem Interactions 

lands throughout the western U.S. Ho 

Bureau of Land Management (BLM) 

resource managers can better understand the consequences of difIntegrated Fire Science 

Many challenging natural resource management issues require considerand temporal complexity of these ecosystem problems demands an interdisciplinary approach integrating biotic and abiotic processes. The goals of 

the Ecosystem Dynamics Branch are to provide sound science to aid federal 

resource managers and use long-term, place-focused research and monitoring on federal lands to advance ecosystem science. 

Current studies fall into five general areas. Herbivore-Ecosystem Interactions examines the efficacy of multiple controls on selected herbivore populations and cascading effects through predator-herbivore-plant-soil linkages. 

Riparian Ecology is concerned with interactions among streamflow, fluvial geomorphology, and riparian vegetation. Integrated Fire 

Science focuses on the effects of fire on plant and animal communities at multiple scales, and on the interactions between post-fire plant, 

runoff, and erosion processes. Reference Ecosystems comprises long-term, place-based studies of ecosystem biogeochemistry. Finally, 

Integrated Assessments is investigating how to synthesize multiple ecosystem stressors and responses over complex landscapes in ways 

The problem of “overabundance” applies both 

to elk and to wild horses and burros on federal 

many ungulates are “too many” is a question 

for many national parks and other federal 

lands. Scientists at the Fort Collins 

Science Center (FORT) have conducted 

studies in Grand Teton, Yellowstone, 

and Rocky Mountain National Parks 

to evaluate the effects of elk herbivory 

on vegetation communities and 

nitrogen processes. Similarly, the 

oversees thousands of wild horses and burros on millions of acres, 

dependence of riparian systems on streamflow and their desirability 

for a number of human activities and uses make them vulnerable 

to human impacts. FORT scientists are studying the factors that 

generate change in riparian systems to improve the scientific basis 

for management decisions. For example, relations between river 

hydrology and the distribution and abundance of riparian plant and 

animal species are being quantified at multiple sites in the Upper 

Colorado, Missouri, and Bill Williams River systems so that water 

ferent flow scenarios. Other riparian research studies at FORT are 

addressing the role of vegetation in mediating flows of water and 

sediment, and the responses of riparian vegetation to dam removal 

and alluvial groundwater decline. 

Fire affects many biotic and abiotic components of ecosystems, 

in addition to its substantial economic and social ramifications. 

Although the ecological importance of fire is widely accepted, 

sound fire management requires 

greater understanding of the 

effects of fire on public lands. 

FORT scientists are leading 

a team of experts in ecology, 

hydrology, geology, and social 

science in a multidisciplinary 

research effort on wildland fire 

effects in the Rocky Mountain 

West. This team is investigating 

the use of remote sensing data 

to compare pre- and post-fire 

U.S. Department of the Interior Fact Sheet 2004–3147 

U.S. Geological Survey December 2004 
fects of change 

effects on avian communities, plant communities, nonnative plant 

invasion, erosion, and debris flow to learn how fire severity is 

affected by various fire management practices. Field data are being 

used to assess the efficacy of Landsat images. Social science incorporates how people living in fire-affected communities view fire 

management. This interdisciplinary approach will help managers 

integrate and evaluate the trade-offs among different fire management 

policies and practices, including prescribed fire, non-fire treatments, 

fire management in the wildland-urban interface, and post-fire rehabilitation and restoration. 

Staff 

Branch Chief: Zack Bowen, Ph.D. Fishery Biologist: stream ecology, instream flow, impact analysis. 

Allen, Craig, Ph.D. Ecologist: landscape ecology, forest ecology, 

biogeography, fire ecology, conservation biology, management applications of ecological information. 

Andersen, Douglas, Ph.D. Ecologist: ecosystem, community, and 

population ecology; plant-animal interactions; terrestrial and riparian ecology. 

Auble, Greg, Ph.D. Ecologist: riparian and wetland ecology, modeling, hydrology, operations research analysis, computer applications. Reference Ecosystems 

helps managers anticipate and plan for

Understanding the long-term ef Baron, Jill, Ph.D. Ecologist: biogeochemical cycling/ecosystem 

ecology, water resources, watershed research, disturbance to alpine 

change in both their short- and subalpine ecosystems, regional integrated ecosystem analysis. 

and long-term resource Friedman, Jonathan, Ph.D. Hydrologist: riparian and wetland ecolmanagement de- ogy, dendrochronology, geomorphology, hydrology, plant commucisions. Over the nity ecology. 

decades, USGS Hogan, John, B.S. Physical Scientist: ecological field work, data 

scientists have collection and management, environmental education, and comdeveloped a munity-based science activities. 

reference eco- Kotliar, Natasha, Ph.D. Research Wildlife Biologist: avian ecology, 

system network fire ecology, wetland dynamics, landscape ecology, prairie dog 

comprising sites ecosystems. 

protected from changes Ouren, Doug. Ph.D. candidate. Physical Scientist: Habitat analysis, 

in local land use. They are located on national park and national 

forest lands from the Arctic to South Texas, and from the mountains 

of North Carolina to the Olympic Coast in Washington. Basic ecosystem study is conducted on each to assess the long-term effects 

of global change, especially from climate and atmospheric contaminant inputs. Owing to the long-term, ecosystem-level research 

design, the studies provide a unique perspective on the effects of 

human activity on natural areas. In a similar vein, FORT scientists staffing the Jemez Mountains Field Station are permanently 

stationed at Bandelier National Park, New Mexico, where they offer 

an on-site, place-based approach to science. The scientists design, 

conduct, and oversee long-term, landscape-scale research and monitoring activities for Bandelier and surrounding wildland areas. 

Integrated Assessments 

Covering about one-fifth of the state of Colorado, the South Platte 

Basin includes a vast diversity of landscapes: extensive national 

forests and parks along the Continental Divide to the west, a growing urban corridor at the mountain/plains boundary, and agricultural 

and rangelands that stretch eastward to the state border. As such, 

this region contains Colorado’s most productive agricultural counties, the vast bulk of its population, and a large proportion of the 

people that recreate on public lands at the top of the basin. Consequently, human activity is a significant contributor to change in the 

South Platte environment. Population growth, land use, water use 

and quality, and climate change continue to be major stressors on 

this system. FORT scientists have initiated a cooperative integrated 

assessment effort among state and federal agencies and universities 

to provide objective, spatially-explicit information on the state of 

the environment and natural resources of the South Platte Basin. 

The objective of the South Platte Integrated Assessment is to understand the complicated interactions between societal activities and 

public lands and resources, identify critical issues, and provide the 

science to inform future planning and management decisions. 

GPS wildlife applications, road ecology. 

Roelle, James, Ph.D. Supervisory Wildlife Biologist: population 

dynamics, modeling, computer applications, riparian ecology. 

Schoenecker, Kate, M.S. Ecologist: bighorn sheep and wild horse 

ecology and behavior, human effects of wildlife, conservation of 

unique and small wild horse populations, natural resource policy. 

Scott, Mike, Ph.D. Ecologist: riparian and wetland ecology, dendrochronology, botany, forest ecology, fluvial geomorphology, plant 

community ecology. 

Shafroth, Pat, Ph.D. Ecologist (Plants): riparian and wetland 

ecology, botany. 

Singer, Francis, Ph.D. Ecologist: conservation biology, large mammal population dynamics, mammalian predator dynamics, and ungulate herbivory, census techniques, and restoration. 

Stottlemyer, Robert, Ph.D. Ecologist: ecosystem and watershed issues in parks, biogeochemistry, carbon and nutrient cycling. 

Zeigenfuss, Linda, M.S. Ecologist: ungulate-plant interactions, ungulate habitat selection and population dynamics, ecological fi eld work. 

Contact Information 

Zack Bowen, Branch Chief 

Fort Collins, Colorado 80526-8118 

Fax 970.226.9230 zack_bowen@usgs.gov 

FORT Online 

Find information about FORT science, products, and resources at 

Learn more about the Ecosystem Dynamics Branch at 

U.S. Geological Survey, Fort Collins Science Center 

2150 Centre Avenue, Building C 

Tel. 970.226.9218 

http://www.fort.usgs.gov 

http://www.fort.usgs.gov/research/200/200.asp