: This document presents a series of technical guidelines by which land cover information is bein... more : This document presents a series of technical guidelines by which land cover information is being extracted from Landsat Thematic Mapper data as part of the Upper Midwest Gap Analysis Program (UMGAP). The UMGAP represents a regionally coordinated implementation of the national Gap Analysis Program in the states of Michigan, Minnesota, and Wisconsin; the program is led by the U.S. Geological Survey, Environmental Management Technical Center. The protocol describes both the underlying philosophy and the operational details of the land cover classification activities being performed as part of UMGAP. Topics discussed include the hierarchical classification scheme, ground reference data acquisition, image stratification, and classification techniques. This discussion is primarily aimed at the image processing analysts involved in the UMGAP land cover mapping activities as well as others involved in similar projects. It is a how to technical guide for a relatively narrow audience, namel...
Native trout are culturally and ecologically important, but also likely to undergo widespread dec... more Native trout are culturally and ecologically important, but also likely to undergo widespread declines as the coldwater environments they require continue to shrink in association with global warming. Much can be done to preserve these fish but efficient planning and targeting of conservations resources has been hindered by a lack of broad-scale datasets and precise information about which streams are most likely to support native trout populations later this century. Using accurate stream temperature climate scenarios developed in the NorWeST project, we identify stream habitats for native Cutthroat Trout Oncorhynchus clarkii and Bull Trout Salvelinus confluentus across northern Idaho and northwestern Montana that are cold enough to serve as climate refugia and resist invasions by nonnative trout. Climate-safe coldwater habitats for Cutthroat Trout in the historical scenario encompassed 7,547 – 16,821 stream kilometers (depending on the local co-occurrence of Brook Trout Salvelinus...
Thermal regimes are fundamental determinants of aquatic ecosystems, which makes description and p... more Thermal regimes are fundamental determinants of aquatic ecosystems, which makes description and prediction of temperatures critical during a period of rapid global change. The advent of inexpensive temperature sensors dramatically increased monitoring in recent decades, and although most monitoring is done by individuals for agency-specific purposes, collectively these efforts constitute a massive distributed sensing array that generates an untapped wealth of data. Using the framework provided by the National Hydrography Dataset, we organized temperature records from dozens of agencies in the western U.S. to create the NorWeST database that hosts >220,000,000 temperature recordings from >22,700 stream and river sites. Spatial-stream-network models were fit to a subset of those data that described mean August water temperatures (AugTw) during 63,641 monitoring site-years to develop accurate temperature models (r2 = 0.91; RMSPE = 1.10°C; MAPE = 0.72°C), assess covariate effects, and make predictions at 1 km intervals to create summer climate scenarios. AugTw averaged 14.2°C (SD = 4.0°C) during the baseline period of 1993–2011 in 343,000 km of western perennial streams but trend reconstructions also indicated warming had occurred at the rate of 0.17°C/decade (SD = 0.067°C/decade) during the 40 year period of 1976–2015. Future scenarios suggest continued warming, although variation will occur within and among river networks due to differences in local climate forcing and stream responsiveness. NorWeST scenarios and data are available online in user-friendly digital formats and are widely used to coordinate monitoring efforts among agencies, for new research, and for conservation planning.
Canadian Journal of Fisheries and Aquatic Sciences
Population size estimates for stream fishes are important for conservation and management, but sa... more Population size estimates for stream fishes are important for conservation and management, but sampling costs limit the extent of most estimates to small portions of river networks that encompass 100s–10 000s of linear kilometres. However, the advent of large fish density data sets, spatial-stream-network (SSN) models that benefit from nonindependence among samples, and national geospatial database frameworks for streams provide the components to create a broadly scalable approach to population estimation. We demonstrate such an approach with density surveys for trout species from 108 sites in a 735 km river network. Universal kriging was used to predict a continuous map of densities among survey locations, and block kriging (BK) was used to summarize discrete map areas and make population estimates at stream, river, and network scales. The SSN models also accommodate covariates, which facilitates hypothesis testing and provides insights about factors affecting patterns of abundance...
Among the many threats posed by invasions of nonnative species is introgressive hybridization, wh... more Among the many threats posed by invasions of nonnative species is introgressive hybridization, which can lead to the genomic extinction of native taxa. This phenomenon is regarded as common and perhaps inevitable among native cutthroat trout and introduced rainbow trout in western North America, despite that these taxa naturally co-occur in some locations. We conducted a synthetic analysis of 13,315 genotyped fish from 558 sites by building logistic regression models using data from geospatial stream databases and from 12 published studies of hybridization to assess whether environmental covariates could explain levels of introgression between westslope cutthroat trout and rainbow trout in the U.S. northern Rocky Mountains. A consensus model performed well (AUC, 0.78-0.86; classification success, 72-82%; 10-fold cross validation, 70-82%) and predicted that rainbow trout introgression was significantly associated with warmer water temperatures, larger streams, proximity to warmer hab...
Proceedings of the National Academy of Sciences of the United States of America, Jan 4, 2016
The imminent demise of montane species is a recurrent theme in the climate change literature, par... more The imminent demise of montane species is a recurrent theme in the climate change literature, particularly for aquatic species that are constrained to networks and elevational rather than latitudinal retreat as temperatures increase. Predictions of widespread species losses, however, have yet to be fulfilled despite decades of climate change, suggesting that trends are much weaker than anticipated and may be too subtle for detection given the widespread use of sparse water temperature datasets or imprecise surrogates like elevation and air temperature. Through application of large water-temperature databases evaluated for sensitivity to historical air-temperature variability and computationally interpolated to provide high-resolution thermal habitat information for a 222,000-km network, we estimate a less dire thermal plight for cold-water species within mountains of the northwestern United States. Stream warming rates and climate velocities were both relatively low for 1968-2011 (a...
Canadian Journal of Fisheries and Aquatic Sciences, 2011
Recent and projected climate warming trends have prompted interest in impacts on coldwater fishes... more Recent and projected climate warming trends have prompted interest in impacts on coldwater fishes. We examined the role of climate (temperature and flow regime) relative to geomorphology and land use in determining the observed distributions of three trout species in the interior Columbia River Basin, USA. We considered two native species, cutthroat trout ( Oncorhynchus clarkii ) and bull trout ( Salvelinus confluentus ), as well as nonnative brook trout ( Salvelinus fontinalis ). We also examined the response of the native species to the presence of brook trout. Analyses were conducted using multilevel logistic regression applied to a geographically broad database of 4165 fish surveys. The results indicated that bull trout distributions were strongly related to climatic factors, and more weakly related to the presence of brook trout and geomorphic variables. Cutthroat trout distributions were weakly related to climate but strongly related to the presence of brook trout. Brook trout...
This document presents a series of technical guidelines by which land cover information is being ... more This document presents a series of technical guidelines by which land cover information is being extracted from Landsat Thematic Mapper data as part of the Upper Midwest Gap Analysis Program (UMGAP). The UMGAP represents a regionally coordinated implementation of the ...
: This document presents a series of technical guidelines by which land cover information is bein... more : This document presents a series of technical guidelines by which land cover information is being extracted from Landsat Thematic Mapper data as part of the Upper Midwest Gap Analysis Program (UMGAP). The UMGAP represents a regionally coordinated implementation of the national Gap Analysis Program in the states of Michigan, Minnesota, and Wisconsin; the program is led by the U.S. Geological Survey, Environmental Management Technical Center. The protocol describes both the underlying philosophy and the operational details of the land cover classification activities being performed as part of UMGAP. Topics discussed include the hierarchical classification scheme, ground reference data acquisition, image stratification, and classification techniques. This discussion is primarily aimed at the image processing analysts involved in the UMGAP land cover mapping activities as well as others involved in similar projects. It is a how to technical guide for a relatively narrow audience, namel...
Native trout are culturally and ecologically important, but also likely to undergo widespread dec... more Native trout are culturally and ecologically important, but also likely to undergo widespread declines as the coldwater environments they require continue to shrink in association with global warming. Much can be done to preserve these fish but efficient planning and targeting of conservations resources has been hindered by a lack of broad-scale datasets and precise information about which streams are most likely to support native trout populations later this century. Using accurate stream temperature climate scenarios developed in the NorWeST project, we identify stream habitats for native Cutthroat Trout Oncorhynchus clarkii and Bull Trout Salvelinus confluentus across northern Idaho and northwestern Montana that are cold enough to serve as climate refugia and resist invasions by nonnative trout. Climate-safe coldwater habitats for Cutthroat Trout in the historical scenario encompassed 7,547 – 16,821 stream kilometers (depending on the local co-occurrence of Brook Trout Salvelinus...
Thermal regimes are fundamental determinants of aquatic ecosystems, which makes description and p... more Thermal regimes are fundamental determinants of aquatic ecosystems, which makes description and prediction of temperatures critical during a period of rapid global change. The advent of inexpensive temperature sensors dramatically increased monitoring in recent decades, and although most monitoring is done by individuals for agency-specific purposes, collectively these efforts constitute a massive distributed sensing array that generates an untapped wealth of data. Using the framework provided by the National Hydrography Dataset, we organized temperature records from dozens of agencies in the western U.S. to create the NorWeST database that hosts >220,000,000 temperature recordings from >22,700 stream and river sites. Spatial-stream-network models were fit to a subset of those data that described mean August water temperatures (AugTw) during 63,641 monitoring site-years to develop accurate temperature models (r2 = 0.91; RMSPE = 1.10°C; MAPE = 0.72°C), assess covariate effects, and make predictions at 1 km intervals to create summer climate scenarios. AugTw averaged 14.2°C (SD = 4.0°C) during the baseline period of 1993–2011 in 343,000 km of western perennial streams but trend reconstructions also indicated warming had occurred at the rate of 0.17°C/decade (SD = 0.067°C/decade) during the 40 year period of 1976–2015. Future scenarios suggest continued warming, although variation will occur within and among river networks due to differences in local climate forcing and stream responsiveness. NorWeST scenarios and data are available online in user-friendly digital formats and are widely used to coordinate monitoring efforts among agencies, for new research, and for conservation planning.
Canadian Journal of Fisheries and Aquatic Sciences
Population size estimates for stream fishes are important for conservation and management, but sa... more Population size estimates for stream fishes are important for conservation and management, but sampling costs limit the extent of most estimates to small portions of river networks that encompass 100s–10 000s of linear kilometres. However, the advent of large fish density data sets, spatial-stream-network (SSN) models that benefit from nonindependence among samples, and national geospatial database frameworks for streams provide the components to create a broadly scalable approach to population estimation. We demonstrate such an approach with density surveys for trout species from 108 sites in a 735 km river network. Universal kriging was used to predict a continuous map of densities among survey locations, and block kriging (BK) was used to summarize discrete map areas and make population estimates at stream, river, and network scales. The SSN models also accommodate covariates, which facilitates hypothesis testing and provides insights about factors affecting patterns of abundance...
Among the many threats posed by invasions of nonnative species is introgressive hybridization, wh... more Among the many threats posed by invasions of nonnative species is introgressive hybridization, which can lead to the genomic extinction of native taxa. This phenomenon is regarded as common and perhaps inevitable among native cutthroat trout and introduced rainbow trout in western North America, despite that these taxa naturally co-occur in some locations. We conducted a synthetic analysis of 13,315 genotyped fish from 558 sites by building logistic regression models using data from geospatial stream databases and from 12 published studies of hybridization to assess whether environmental covariates could explain levels of introgression between westslope cutthroat trout and rainbow trout in the U.S. northern Rocky Mountains. A consensus model performed well (AUC, 0.78-0.86; classification success, 72-82%; 10-fold cross validation, 70-82%) and predicted that rainbow trout introgression was significantly associated with warmer water temperatures, larger streams, proximity to warmer hab...
Proceedings of the National Academy of Sciences of the United States of America, Jan 4, 2016
The imminent demise of montane species is a recurrent theme in the climate change literature, par... more The imminent demise of montane species is a recurrent theme in the climate change literature, particularly for aquatic species that are constrained to networks and elevational rather than latitudinal retreat as temperatures increase. Predictions of widespread species losses, however, have yet to be fulfilled despite decades of climate change, suggesting that trends are much weaker than anticipated and may be too subtle for detection given the widespread use of sparse water temperature datasets or imprecise surrogates like elevation and air temperature. Through application of large water-temperature databases evaluated for sensitivity to historical air-temperature variability and computationally interpolated to provide high-resolution thermal habitat information for a 222,000-km network, we estimate a less dire thermal plight for cold-water species within mountains of the northwestern United States. Stream warming rates and climate velocities were both relatively low for 1968-2011 (a...
Canadian Journal of Fisheries and Aquatic Sciences, 2011
Recent and projected climate warming trends have prompted interest in impacts on coldwater fishes... more Recent and projected climate warming trends have prompted interest in impacts on coldwater fishes. We examined the role of climate (temperature and flow regime) relative to geomorphology and land use in determining the observed distributions of three trout species in the interior Columbia River Basin, USA. We considered two native species, cutthroat trout ( Oncorhynchus clarkii ) and bull trout ( Salvelinus confluentus ), as well as nonnative brook trout ( Salvelinus fontinalis ). We also examined the response of the native species to the presence of brook trout. Analyses were conducted using multilevel logistic regression applied to a geographically broad database of 4165 fish surveys. The results indicated that bull trout distributions were strongly related to climatic factors, and more weakly related to the presence of brook trout and geomorphic variables. Cutthroat trout distributions were weakly related to climate but strongly related to the presence of brook trout. Brook trout...
This document presents a series of technical guidelines by which land cover information is being ... more This document presents a series of technical guidelines by which land cover information is being extracted from Landsat Thematic Mapper data as part of the Upper Midwest Gap Analysis Program (UMGAP). The UMGAP represents a regionally coordinated implementation of the ...
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