Darius Semmens (Former Employee)
Science and Products
Filter Total Items: 76
Density estimates of monarch butterflies overwintering in central Mexico Density estimates of monarch butterflies overwintering in central Mexico
Given the rapid population decline and recent petition for listing of the monarch butterfly (Danaus plexippus L.) under the Endangered Species Act, an accurate estimate of the Eastern, migratory population size is needed. Because of difficulty in counting individual monarchs, the number of hectares occupied by monarchs in the overwintering area is commonly used as a proxy for population...
Authors
Wayne E. Thogmartin, James E. Diffendorfer, Laura Lopez-Hoffman, Karen Oberhauser, John M. Pleasants, Brice X. Semmens, Darius J. Semmens, Orley R. Taylor, Ruscena Wiederholt
Operationalizing the telecoupling framework for migratory species using the spatial subsidies approach to examine ecosystem services provided by Mexican free-tailed bats Operationalizing the telecoupling framework for migratory species using the spatial subsidies approach to examine ecosystem services provided by Mexican free-tailed bats
Drivers of environmental change in one location can have profound effects on ecosystem services and human well-being in distant locations, often across international borders. The telecoupling provides a conceptual framework for describing these interactions—for example, locations can be defined as sending areas (sources of flows of ecosystem services, energy, or information) or receiving...
Authors
Laura Lopez Hoffman, James E. Diffendorfer, Ruscena Widerholt, Wayne E. Thogmartin, Gary McCraken, Rodrigo Medellin, Kenneth J. Bagstad, Amy Russell, Darius J. Semmens
A trans-national monarch butterfly population model and implications for regional conservation priorities A trans-national monarch butterfly population model and implications for regional conservation priorities
1. The monarch has undergone considerable population declines over the past decade, and the governments of Mexico, Canada, and the United States have agreed to work together to conserve the species. 2. Given limited resources, understanding where to focus conservation action is key for widespread species like monarchs. To support planning for continental-scale monarch habitat restoration...
Authors
Karen Oberhauser, Ruscena Wiederholt, James E. Diffendorfer, Darius J. Semmens, Leslie Ries, Wayne E. Thogmartin, Laura Lopez-Hoffman, Brice Semmens
Improving spatio-temporal benefit transfers for pest control by generalist predators in cotton in the southwestern U.S. Improving spatio-temporal benefit transfers for pest control by generalist predators in cotton in the southwestern U.S.
Given rapid changes in agricultural practice, it is critical to understand how alterations in ecological, technological, and economic conditions over time and space impact ecosystem services in agroecosystems. Here, we present a benefit transfer approach to quantify cotton pest-control services provided by a generalist predator, the Mexican free-tailed bat (Tadarida brasiliensis mexicana...
Authors
Ruscena Wiederholt, Kenneth J. Bagstad, Gary F. McCracken, Jay E. Diffendorfer, John B. Loomis, Darius J. Semmens, Amy L. Russell, Chris Sansone, Kelsie LaSharr, Paul M. Cryan, Claudia Reynoso, Rodrigo A. Medellin, Laura Lopez-Hoffman
Evaluating alternative methods for biophysical and cultural ecosystem services hotspot mapping in natural resource planning Evaluating alternative methods for biophysical and cultural ecosystem services hotspot mapping in natural resource planning
Context Data for biophysically modeled and Public Participatory GIS (PPGIS)-derived cultural ecosystem services have potential to identify natural resource management synergies and conflicts, but have rarely been combined. Ecosystem service hot/coldspots generated using different methods vary in their spatial extent and connectivity, with important implications. Objectives We map...
Authors
Kenneth J. Bagstad, Darius J. Semmens, Zachary H. Ancona, Benson C. Sherrouse
A management-oriented framework for selecting metrics used to assess habitat- and path-specific quality in spatially structured populations A management-oriented framework for selecting metrics used to assess habitat- and path-specific quality in spatially structured populations
Mobile species with complex spatial dynamics can be difficult to manage because their population distributions vary across space and time, and because the consequences of managing particular habitats are uncertain when evaluated at the level of the entire population. Metrics to assess the importance of habitats and pathways connecting habitats in a network are necessary to guide a...
Authors
Sam Nicol, Ruscena Wiederholt, James E. Diffendorfer, Brady J. Mattsson, Wayne E. Thogmartin, Darius J. Semmens, Laura Lopez-Hoffman, Ryan Norris
Non-USGS Publications**
Liu, Y., Mahmoud, M., Hartmann, H., Stewart, S., Wagener, T., Semmens, D., Stewart, R., Gupta, H., Dominguez, D., Hulse, D., Letcher, R., Rashleigh, B., Smith, C., Street, R., Ticehurst, J., Twery, M., van Delden, H., Waldick, R., White, D., and Winter, L., 2008, Formal scenario development for environmental impact assessment studies, in Jakeman, A., A. Voinov, A. E. Rizzoli, and S. Chen, (Eds.) Environmental Modelling, Software and Decision Support, 3. IDEA Book Series, Elsevier, 338 pp.
Kepner, W.G., Hernandez, M., Semmens, D.J., and Goodrich D.C.,2008, The Use of Scenario Analysis to Assess Future Landscape Change on Watershed Condition in the Pacific Northwest (USA), in Use of Landscape Sciences for Environmental Security: NATO Security through Science Series, Springer Publishers, The Netherlands. ISBN 978-1-4020-6588-0, pp. 237-261.
Kepner, W.G., Semmens, D.J., Hernandez, M., and Goodrich, D.C., 2008, Evaluating Hydrological Response to Forecasted Land-use Change, Chapter 15 in Special Issue of Association of American Geographers. North American Land Cover Summit. Washington, DC. pp. 275-292. ISBN 978-0-89291-271-1.
Semmens, D.J., Goodrich, D.C., Unkrich, C.L., Smith, R.E., Woolhiser, D.A., and Miller, S.N., 2008, KINEROS2 and the AGWA modeling framework, in Wheater, H., Sorooshian, S., and Sharma, K.D., eds., Hydrological Modelling In Arid and Semi-Arid Areas: Cambridge University Press, New York, 206pp.
Miller, S.N., Semmens, D.J., Goodrich, D.C., Hernandez, M., Miller, R.C., Kepner, W.G., and Guertin, D.P., 2007, The Automated Geospatial Watershed Assessment tool: Environmental Modeling and Software, v. 22, n. 3, p. 365-377.
Nikolova, M., S. Nedkov, D. Semmens, and S. Iankov, 2007, Environmental quality and landscape-risk assessment in the Yantra River Basin, in W. Kepner, W., Müller, F., Petrosillio, I., Jones, B., Krauze, K., Victorov, S., and Zurlini, G., (eds.), Use of Landscape Sciences for the Assessment of Environmental Security: NATO Security Through Science Series, Springer Publications, p. 202-217.
Kepner, W.G., Semmens, D.J., Basset, S.D., Mouat, D.A., Goodrich, D.C., 2004, Scenario analysis for the San Pedro River, analyzing hydrological consequences for a future environment: Environmental Modeling and Assessment, v. 94, p. 115-127.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 76
Density estimates of monarch butterflies overwintering in central Mexico Density estimates of monarch butterflies overwintering in central Mexico
Given the rapid population decline and recent petition for listing of the monarch butterfly (Danaus plexippus L.) under the Endangered Species Act, an accurate estimate of the Eastern, migratory population size is needed. Because of difficulty in counting individual monarchs, the number of hectares occupied by monarchs in the overwintering area is commonly used as a proxy for population...
Authors
Wayne E. Thogmartin, James E. Diffendorfer, Laura Lopez-Hoffman, Karen Oberhauser, John M. Pleasants, Brice X. Semmens, Darius J. Semmens, Orley R. Taylor, Ruscena Wiederholt
Operationalizing the telecoupling framework for migratory species using the spatial subsidies approach to examine ecosystem services provided by Mexican free-tailed bats Operationalizing the telecoupling framework for migratory species using the spatial subsidies approach to examine ecosystem services provided by Mexican free-tailed bats
Drivers of environmental change in one location can have profound effects on ecosystem services and human well-being in distant locations, often across international borders. The telecoupling provides a conceptual framework for describing these interactions—for example, locations can be defined as sending areas (sources of flows of ecosystem services, energy, or information) or receiving...
Authors
Laura Lopez Hoffman, James E. Diffendorfer, Ruscena Widerholt, Wayne E. Thogmartin, Gary McCraken, Rodrigo Medellin, Kenneth J. Bagstad, Amy Russell, Darius J. Semmens
A trans-national monarch butterfly population model and implications for regional conservation priorities A trans-national monarch butterfly population model and implications for regional conservation priorities
1. The monarch has undergone considerable population declines over the past decade, and the governments of Mexico, Canada, and the United States have agreed to work together to conserve the species. 2. Given limited resources, understanding where to focus conservation action is key for widespread species like monarchs. To support planning for continental-scale monarch habitat restoration...
Authors
Karen Oberhauser, Ruscena Wiederholt, James E. Diffendorfer, Darius J. Semmens, Leslie Ries, Wayne E. Thogmartin, Laura Lopez-Hoffman, Brice Semmens
Improving spatio-temporal benefit transfers for pest control by generalist predators in cotton in the southwestern U.S. Improving spatio-temporal benefit transfers for pest control by generalist predators in cotton in the southwestern U.S.
Given rapid changes in agricultural practice, it is critical to understand how alterations in ecological, technological, and economic conditions over time and space impact ecosystem services in agroecosystems. Here, we present a benefit transfer approach to quantify cotton pest-control services provided by a generalist predator, the Mexican free-tailed bat (Tadarida brasiliensis mexicana...
Authors
Ruscena Wiederholt, Kenneth J. Bagstad, Gary F. McCracken, Jay E. Diffendorfer, John B. Loomis, Darius J. Semmens, Amy L. Russell, Chris Sansone, Kelsie LaSharr, Paul M. Cryan, Claudia Reynoso, Rodrigo A. Medellin, Laura Lopez-Hoffman
Evaluating alternative methods for biophysical and cultural ecosystem services hotspot mapping in natural resource planning Evaluating alternative methods for biophysical and cultural ecosystem services hotspot mapping in natural resource planning
Context Data for biophysically modeled and Public Participatory GIS (PPGIS)-derived cultural ecosystem services have potential to identify natural resource management synergies and conflicts, but have rarely been combined. Ecosystem service hot/coldspots generated using different methods vary in their spatial extent and connectivity, with important implications. Objectives We map...
Authors
Kenneth J. Bagstad, Darius J. Semmens, Zachary H. Ancona, Benson C. Sherrouse
A management-oriented framework for selecting metrics used to assess habitat- and path-specific quality in spatially structured populations A management-oriented framework for selecting metrics used to assess habitat- and path-specific quality in spatially structured populations
Mobile species with complex spatial dynamics can be difficult to manage because their population distributions vary across space and time, and because the consequences of managing particular habitats are uncertain when evaluated at the level of the entire population. Metrics to assess the importance of habitats and pathways connecting habitats in a network are necessary to guide a...
Authors
Sam Nicol, Ruscena Wiederholt, James E. Diffendorfer, Brady J. Mattsson, Wayne E. Thogmartin, Darius J. Semmens, Laura Lopez-Hoffman, Ryan Norris
Non-USGS Publications**
Liu, Y., Mahmoud, M., Hartmann, H., Stewart, S., Wagener, T., Semmens, D., Stewart, R., Gupta, H., Dominguez, D., Hulse, D., Letcher, R., Rashleigh, B., Smith, C., Street, R., Ticehurst, J., Twery, M., van Delden, H., Waldick, R., White, D., and Winter, L., 2008, Formal scenario development for environmental impact assessment studies, in Jakeman, A., A. Voinov, A. E. Rizzoli, and S. Chen, (Eds.) Environmental Modelling, Software and Decision Support, 3. IDEA Book Series, Elsevier, 338 pp.
Kepner, W.G., Hernandez, M., Semmens, D.J., and Goodrich D.C.,2008, The Use of Scenario Analysis to Assess Future Landscape Change on Watershed Condition in the Pacific Northwest (USA), in Use of Landscape Sciences for Environmental Security: NATO Security through Science Series, Springer Publishers, The Netherlands. ISBN 978-1-4020-6588-0, pp. 237-261.
Kepner, W.G., Semmens, D.J., Hernandez, M., and Goodrich, D.C., 2008, Evaluating Hydrological Response to Forecasted Land-use Change, Chapter 15 in Special Issue of Association of American Geographers. North American Land Cover Summit. Washington, DC. pp. 275-292. ISBN 978-0-89291-271-1.
Semmens, D.J., Goodrich, D.C., Unkrich, C.L., Smith, R.E., Woolhiser, D.A., and Miller, S.N., 2008, KINEROS2 and the AGWA modeling framework, in Wheater, H., Sorooshian, S., and Sharma, K.D., eds., Hydrological Modelling In Arid and Semi-Arid Areas: Cambridge University Press, New York, 206pp.
Miller, S.N., Semmens, D.J., Goodrich, D.C., Hernandez, M., Miller, R.C., Kepner, W.G., and Guertin, D.P., 2007, The Automated Geospatial Watershed Assessment tool: Environmental Modeling and Software, v. 22, n. 3, p. 365-377.
Nikolova, M., S. Nedkov, D. Semmens, and S. Iankov, 2007, Environmental quality and landscape-risk assessment in the Yantra River Basin, in W. Kepner, W., Müller, F., Petrosillio, I., Jones, B., Krauze, K., Victorov, S., and Zurlini, G., (eds.), Use of Landscape Sciences for the Assessment of Environmental Security: NATO Security Through Science Series, Springer Publications, p. 202-217.
Kepner, W.G., Semmens, D.J., Basset, S.D., Mouat, D.A., Goodrich, D.C., 2004, Scenario analysis for the San Pedro River, analyzing hydrological consequences for a future environment: Environmental Modeling and Assessment, v. 94, p. 115-127.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.