David P Hockman-Wert (Former Employee)
Science and Products
Probability of Streamflow Permanence (PROSPER)
PRObability of Streamflow PERmanence (PROSPER)
Rivers and streams are constantly changing. Streamflows can change throughout the year and between years due to snowmelt, precipitation, diversions, and return flows. For many streams, these fluctuations determine whether a stream has year-round flow or not. PROSPER is a project initiated to better understand what causes these fluctuations...
Aquatic & Landscape Ecology Research Team (FRESC)
Fresh waters are one of the most valuable and threatened resources worldwide. They supply critical services to society and harbor many of the world’s most imperiled species. We conduct research and provide technical assistance to address challenges to fresh waters. Our research focuses on ecological processes in freshwater and terrestrial systems and the effects of those processes on landscape...
Stream temperature data from Willow-Whitehorse and Little Blitzen watersheds, southeast Oregon, 2011-2015
These tabular, spatial, and code data sets were created in support of a stream temperature monitoring study in the Willow-Whitehorse and Little Blitzen watersheds in southeastern Oregon from 2011-2015.
Land-cover and climatic controls on water temperature, flow permanence, and fragmentation of Great Basin stream networks
The seasonal and inter-annual variability of flow presence and water temperature within headwater streams of the Great Basin of the western United States limit the occurrence and distribution of coldwater fish and other aquatic species. To evaluate changes in flow presence and water temperature during seasonal dry periods, we developed spatial...
Gendaszek, Andrew S.; Dunham, Jason B.; Torgersen, Christian E.; Hockman-Wert, David P; Heck, Michael; Thorson, Justin Martin; Mintz, Jeffrey Michael; Allai, Todd Probability of streamflow permanence model (PROSPER): A spatially continuous model of annual streamflow permanence throughout the Pacific Northwest
The U.S. Geological Survey (USGS) has developed the PRObability of Streamflow PERmanence (PROSPER) model, a GIS raster-based empirical model that provides streamflow permanence probabilities (probabilistic predictions) of a stream channel having year-round flow for any unregulated and minimally-impaired stream channel in the Pacific Northwest...
Jaeger, Kristin; Sando, Thomas R.; McShane, Ryan R.; Dunham, Jason B.; Hockman-Wert, David; Kaiser, Kendra E; Hafen, Konrad; Risley, John; Blasch, Kyle
Monitoring stream temperatures—A guide for non-specialists
Executive SummaryWater temperature influences most physical and biological processes in streams, and along with streamflows is a major driver of ecosystem processes. Collecting data to measure water temperature is therefore imperative, and relatively straightforward. Several protocols exist for collecting stream temperature data, but these are...
Heck, Michael P.; Schultz, Luke D.; Hockman-Wert, David; Dinger, Eric C.; Dunham, Jason B. Fish response to contemporary timber harvest practices in a second-growth forest from the central Coast Range of Oregon
We used a paired-watershed approach to investigate the effects of contemporary logging practices on headwater populations of coastal cutthroat trout (Oncorhynchus clarkii clarkii) and juvenile coho salmon (Oncorhynchus kisutch) in a second-growth Douglas-fir forested catchment in Oregon. Stream habitat and fish population characteristics,...
Bateman, Douglas S.; Gresswell, Robert E.; Warren, Dana; Hockman-Wert, David; Leer, David W.; Light, Jeffrey T.; Stednick, John D. A statistical method to predict flow permanence in dryland streams from time series of stream temperature
Intermittent and ephemeral streams represent more than half of the length of the global river network. Dryland freshwater ecosystems are especially vulnerable to changes in human-related water uses as well as shifts in terrestrial climates. Yet, the description and quantification of patterns of flow permanence in these systems is challenging...
Arismendi, Ivan; Dunham, Jason B.; Heck, Michael; Schultz, Luke; Hockman-Wert, David Spatial and temporal variability in the effects of wildfire and drought on thermal habitat for a desert trout
We studied how drought and an associated stressor, wildfire, influenced stream flow permanence and thermal regimes in a Great Basin stream network. We quantified these responses by collecting information with a spatially extensive network of data loggers. To understand the effects of wildfire specifically, we used data from 4 additional sites that...
Schultz, Luke; Heck, Michael; Hockman-Wert, David; Allai, T; Wenger, Seth J.; Cook, NA; Dunham, Jason B. Effects of stream-adjacent logging in fishless headwaters on downstream coastal cutthroat trout
To investigate effects of headwater logging on downstream coastal cutthroat trout (Oncorhynchus clarkii clarkii) populations, we monitored stream habitat and biotic indicators including biomass, abundance, growth, movement, and survival over 8 years using a paired-watershed approach. Reference and logged catchments were located on private...
Bateman, Douglas S.; Sloat, Matthew R.; Gresswell, Robert E.; Berger, Aaron M.; Hockman-Wert, David; Leer, David W.; Skaugset, Arne E. A simple prioritization tool to diagnose impairment of stream temperature for coldwater fishes in the Great Basin
We provide a simple framework for diagnosing the impairment of stream water temperature for coldwater fishes across broad spatial extents based on a weight-of-evidence approach that integrates biological criteria, species distribution models, and geostatistical models of stream temperature. As a test case, we applied our approach to identify...
Falke, Jeffrey A.; Dunham, Jason B.; Hockman-Wert, David; Pahl, Randy A. Geographic variability in elevation and topographic constraints on the distribution of native and nonnative trout in the Great Basin
Understanding local and geographic factors influencing species distributions is a prerequisite for conservation planning. Our objective in this study was to model local and geographic variability in elevations occupied by native and nonnative trout in the northwestern Great Basin, USA. To this end, we analyzed a large existing data set of trout...
Warren, Dana R.; Dunham, Jason B.; Hockman-Wert, David The paradox of cooling streams in a warming world: Regional climate trends do not parallel variable local trends in stream temperature in the Pacific continental United States
Temperature is a fundamentally important driver of ecosystem processes in streams. Recent warming of terrestrial climates around the globe has motivated concern about consequent increases in stream temperature. More specifically, observed trends of increasing air temperature and declining stream flow are widely believed to result in corresponding...
Arismendi, Ivan; Johnson, Sherri; Dunham, Jason B.; Haggerty, Roy; Hockman-Wert, David
Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon
The Lower Crooked River is a remarkable groundwater-fed stream flowing through vertical basalt canyons in the Deschutes River Valley ecoregion in central Oregon (Pater and others, 1998). The 9-mile section of the river between the Crooked River National Grasslands boundary near Ogden Wayside and river mile (RM) 8 is protected under the National...
Torgersen, Christian E.; Hockman-Wert, David P.; Bateman, Douglas S.; Leer, David W.; Gresswell, Robert E.
A Spatially Continuous Model of Annual Streamflow Permanence Throughout the Pacific Northwest
An interdisciplinary team comprised of USGS and university scientists has developed the Probability of Streamflow Permanence Model or PROSPER which predicts flow permanence for unregulated and minimally impaired streams in the Pacific Northwest.