Influence of Bio-Pollution on Ecosystem Processes: The Impact Introduced Lake Trout on Streams and Terrestrial Predators in Yellowstone National Park

EPA Grant Number: R829426E02
Title: Influence of Bio-Pollution on Ecosystem Processes: The Impact Introduced Lake Trout on Streams and Terrestrial Predators in Yellowstone National Park
Investigators: Hall, Robert O. , Ben-David, Merav
Institution: University of Wyoming
EPA Project Officer: Hunt, Sherri
Project Period: July 15, 2002 through September 30, 2004
Project Amount: $160,610
RFA: EPSCoR (Experimental Program to Stimulate Competitive Research) (2001) RFA Text |  Recipients Lists
Research Category: EPSCoR (The Experimental Program to Stimulate Competitive Research)


Invasive species can impact populations and ecosystem process within the recipient ecosystem, but their impacts outside of this ecosystem are rarely considered. Lake trout have invaded Yellowstone Lake and if left unchecked are predicted to substantially lower native cutthroat trout populations. The impact of fewer native cutthroat trout will almost certainly extend beyond the lake, to trout spawning tributary-streams. We propose to study the impact of a cutthroat trout decline on stream ecosystem processes (such as nitrogen transport) and potential effect of river otters and their transport of nutrients to riparian forests.


We propose to investigate the role of cutthroat trout in structuring stream ecosystems, their importance to river otters, and possible links to terrestrial plants thus integrating in-stream and terrestrial processes. For the element cycling component of this study we focus on nitrogen, because it limits production in streams and terrestrial ecosystems. These observations will enable us to make initial predictions how streams, trout predators, and the terrestrial landscape will be affected following cutthroat trout demise.

Expected Results:

This research will result in broader understanding of impacts of exotic lake trout in Yellowstone. Typically impacts of invaders are considered only in the recipient ecosystem; we will explicitly estimate impacts outside Yellowstone Lake. This research will thus provide a framework for managers to understand ecological links between ecosystems and not just within ecosystems. While the Yellowstone Lake system provides an excellent laboratory for such investigation, results from this project will be applicable to other systems where demise of an important species may lead to rippling effects in adjacent ecosystems. We will train three graduate students who will work towards a Masters degree as part of this project. We will also involve undergraduate students in field and laboratory research.

Publications and Presentations:

Publications have been submitted on this project: View all 24 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 4 journal articles for this project

Supplemental Keywords:

cutthroat trout, invasive species, limnology, nitrogen, nutrient transports, river otters, stream invertebrates, tree cores. Yellowstone., RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Water, ECOSYSTEMS, Ecosystem Protection/Environmental Exposure & Risk, Ecology, Aquatic Ecosystems & Estuarine Research, Water & Watershed, Ecosystem/Assessment/Indicators, Aquatic Ecosystem, Monitoring/Modeling, Ecological Effects - Environmental Exposure & Risk, Water Quality Monitoring, Environmental Monitoring, Terrestrial Ecosystems, Ecology and Ecosystems, Watersheds, anthropogenic processes, nutrient transport, anthropogenic stress, bioassessment, watershed classification, lake trout, biodiversity, watershed management, ecosystem monitoring, biopollution, Yellowstone Park, conservation, diagnostic indicators, lakes, ecosystem indicators, aquatic ecosystems, invasive species, water quality, bioindicators, watershed sustainablility, biological indicators, ecosystem stress, watershed assessment, nitrogen uptake, conservation planning, aquatic biota, land use, restoration planning, watershed restoration, ecosystem response

Progress and Final Reports:

  • 2003 Progress Report
  • 2004 Progress Report
  • Final Report