Timothy Cline, PhD (Former Employee)
Science and Products
Assessing the Vulnerability of Native Trout in the Northern Rockies: Linking Science and Management for Climate Adaptation
Trout are one of the most culturally, economically, and ecologically important groups of freshwater fishes in the Rocky Mountain region. However, human impacts and climate change are significantly altering freshwater ecosystems that support native trout species. Despite their broad importance, many of the region’s trout populations are threatened and some require immediate conservation efforts to
Declines in body size of sockeye salmon associated with increased competition in the ocean
Declining body sizes have been documented for several species of Pacific salmon; however, whether size declines are caused mainly by ocean warming or other ecological factors, and whether they result primarily from trends in age at maturation or changing growth rates remain poorly understood. We quantified changes in mean body size and contributions from shifting size-at-age and age structure of m
Authors
Jan Ohlberger, Timothy Joseph Cline, Daniel Schindler, Bert Lewis
High dispersal rates in hybrids drive expansion of maladaptive hybridization
Hybridization between native and invasive species, a major cause of biodiversity loss, can spread rapidly even when hybrids have reduced fitness. This paradox suggests that hybrids have greater dispersal rates than non-hybridized individuals, yet this mechanism has not been empirically tested in animal populations. Here, we test if non-native genetic introgression increases reproductive dispersal
Authors
Samuel Bourret, Ryan P. Kovach, Timothy Joseph Cline, Jeffrey Strait, Clint C. Muhlfeld
Socioeconomic resilience to climatic extremes in a freshwater fishery
Heterogeneity is a central feature of ecosystem resilience, but how this translates to socioeconomic resilience depends on people’s ability to track shifting resources in space and time. Here, we quantify how climatic extremes have influenced how people (fishers) track economically valuable ecosystem services (fishing opportunities) across a range of spatial scales in rivers of the northern Rocky
Authors
Timothy Joseph Cline, Clint C. Muhlfeld, Ryan P. Kovach, Robert Al-Chokhachy, David Schmetterling, Diane Whited, Abigail Lynch
Stream size, temperature, and density explain body sizes of freshwater salmonids across a range of climate conditions
Climate change and anthropogenic activities are altering the body sizes of fishes, yet our understanding of factors influencing body size for many taxa remains incomplete. We evaluated the relationships between climate, environmental, and landscape attributes and the body size of different taxa of freshwater trout (Salmonidae) in the USA. Hierarchical spatial modeling across a gradient of habitats
Authors
Robert K. Al-Chokhachy, Benjamin Letcher, Clint C. Muhlfeld, Jason B. Dunham, Timothy Joseph Cline, Nathaniel P. Hitt, James Roberts, David Schmetterling
A framework to integrate innovations in invasion science for proactive management
Invasive alien species (IAS) are a rising threat to biodiversity, national security, and regional economies, with impacts in the hundreds of billions of U.S. dollars annually. Proactive or predictive approaches guided by scientific knowledge are essential to keeping pace with growing impacts of invasions under climate change. Although the rapid development of diverse technologies and approaches ha
Authors
Charles B. van Rees, Brian K. Hand, Sean C. Carter, Charles Bargeron, Timothy Joseph Cline, Wesley M. Daniel, Jason A. Ferrante, Keith Gaddis, Margaret E. Hunter, Catherine S. Jarnevich, Melodie A. McGeoch, Jeffrey T. Morisette, Matthew E. Neilson, Helen E. Roy, Mary Ann Rozance, Adam Sepulveda, Rebekah D. Wallace, Diane Whited, Taylor Wilcox, John S. Kimball, Gordon Luikart
Climate change and expanding invasive species drive widespread declines of native trout in the northern Rocky Mountains, USA
Climate change and invasive species are major threats to native biodiversity, but few empirical studies have examined their combined effects at large spatial and temporal scales. Using 21,917 surveys collected over 30 years, we quantified the impacts of climate change on the past and future distributions of five interacting native and invasive trout species throughout the northern Rocky Mountains,
Authors
Donovan A. Bell, Ryan P. Kovach, Clint C. Muhlfeld, Robert Al-Chokhachy, Timothy Joseph Cline, Diane C. Whited, David Schmetterling, Paul M Lukacs, Andrew R. Whiteley
Specialized meltwater biodiversity persists despite widespread deglaciation
Glaciers are important drivers of environmental heterogeneity and biological diversity across mountain landscapes. Worldwide, glaciers are receding rapidly due to climate change, with important consequences for biodiversity in mountain ecosystems. However, the effects of glacier loss on biodiversity have never been quantified across a mountainous region, primarily due to a lack of adequate data at
Authors
Clint C. Muhlfeld, Timothy Joseph Cline, J. Joseph Giersch, Erich Peitzsch, Caitlyn Florentine, Dean Jacobsen, Scott Hotaling
Non-USGS Publications**
Cline, T.J., Ohlberger, J., and Schindler, D.E., 2019, Effects of warming climate and competition in the ocean for life-histories of Pacific salmon: Nature Ecology & Evolution, v. 3, p. 935–942.
Cline, T.J., Schindler, D.E., Hilborn, R., 2017, Fisheries portfolio diversification and turnover buffer Alaskan fishing communities from abrupt resource and market changes: Nature Communications, v: 8, 14042.
Brennan, S.R., Schindler, D.E., Cline, T.J., Walsworth, T.E., Buck, G., and Fernandez, D.P, 2019, Shifting habitat mosaics and fish production across river basins: Science, v. 364, p. 783–786.
**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
Assessing the Vulnerability of Native Trout in the Northern Rockies: Linking Science and Management for Climate Adaptation
Trout are one of the most culturally, economically, and ecologically important groups of freshwater fishes in the Rocky Mountain region. However, human impacts and climate change are significantly altering freshwater ecosystems that support native trout species. Despite their broad importance, many of the region’s trout populations are threatened and some require immediate conservation efforts to
Declines in body size of sockeye salmon associated with increased competition in the ocean
Declining body sizes have been documented for several species of Pacific salmon; however, whether size declines are caused mainly by ocean warming or other ecological factors, and whether they result primarily from trends in age at maturation or changing growth rates remain poorly understood. We quantified changes in mean body size and contributions from shifting size-at-age and age structure of m
Authors
Jan Ohlberger, Timothy Joseph Cline, Daniel Schindler, Bert Lewis
High dispersal rates in hybrids drive expansion of maladaptive hybridization
Hybridization between native and invasive species, a major cause of biodiversity loss, can spread rapidly even when hybrids have reduced fitness. This paradox suggests that hybrids have greater dispersal rates than non-hybridized individuals, yet this mechanism has not been empirically tested in animal populations. Here, we test if non-native genetic introgression increases reproductive dispersal
Authors
Samuel Bourret, Ryan P. Kovach, Timothy Joseph Cline, Jeffrey Strait, Clint C. Muhlfeld
Socioeconomic resilience to climatic extremes in a freshwater fishery
Heterogeneity is a central feature of ecosystem resilience, but how this translates to socioeconomic resilience depends on people’s ability to track shifting resources in space and time. Here, we quantify how climatic extremes have influenced how people (fishers) track economically valuable ecosystem services (fishing opportunities) across a range of spatial scales in rivers of the northern Rocky
Authors
Timothy Joseph Cline, Clint C. Muhlfeld, Ryan P. Kovach, Robert Al-Chokhachy, David Schmetterling, Diane Whited, Abigail Lynch
Stream size, temperature, and density explain body sizes of freshwater salmonids across a range of climate conditions
Climate change and anthropogenic activities are altering the body sizes of fishes, yet our understanding of factors influencing body size for many taxa remains incomplete. We evaluated the relationships between climate, environmental, and landscape attributes and the body size of different taxa of freshwater trout (Salmonidae) in the USA. Hierarchical spatial modeling across a gradient of habitats
Authors
Robert K. Al-Chokhachy, Benjamin Letcher, Clint C. Muhlfeld, Jason B. Dunham, Timothy Joseph Cline, Nathaniel P. Hitt, James Roberts, David Schmetterling
A framework to integrate innovations in invasion science for proactive management
Invasive alien species (IAS) are a rising threat to biodiversity, national security, and regional economies, with impacts in the hundreds of billions of U.S. dollars annually. Proactive or predictive approaches guided by scientific knowledge are essential to keeping pace with growing impacts of invasions under climate change. Although the rapid development of diverse technologies and approaches ha
Authors
Charles B. van Rees, Brian K. Hand, Sean C. Carter, Charles Bargeron, Timothy Joseph Cline, Wesley M. Daniel, Jason A. Ferrante, Keith Gaddis, Margaret E. Hunter, Catherine S. Jarnevich, Melodie A. McGeoch, Jeffrey T. Morisette, Matthew E. Neilson, Helen E. Roy, Mary Ann Rozance, Adam Sepulveda, Rebekah D. Wallace, Diane Whited, Taylor Wilcox, John S. Kimball, Gordon Luikart
Climate change and expanding invasive species drive widespread declines of native trout in the northern Rocky Mountains, USA
Climate change and invasive species are major threats to native biodiversity, but few empirical studies have examined their combined effects at large spatial and temporal scales. Using 21,917 surveys collected over 30 years, we quantified the impacts of climate change on the past and future distributions of five interacting native and invasive trout species throughout the northern Rocky Mountains,
Authors
Donovan A. Bell, Ryan P. Kovach, Clint C. Muhlfeld, Robert Al-Chokhachy, Timothy Joseph Cline, Diane C. Whited, David Schmetterling, Paul M Lukacs, Andrew R. Whiteley
Specialized meltwater biodiversity persists despite widespread deglaciation
Glaciers are important drivers of environmental heterogeneity and biological diversity across mountain landscapes. Worldwide, glaciers are receding rapidly due to climate change, with important consequences for biodiversity in mountain ecosystems. However, the effects of glacier loss on biodiversity have never been quantified across a mountainous region, primarily due to a lack of adequate data at
Authors
Clint C. Muhlfeld, Timothy Joseph Cline, J. Joseph Giersch, Erich Peitzsch, Caitlyn Florentine, Dean Jacobsen, Scott Hotaling
Non-USGS Publications**
Cline, T.J., Ohlberger, J., and Schindler, D.E., 2019, Effects of warming climate and competition in the ocean for life-histories of Pacific salmon: Nature Ecology & Evolution, v. 3, p. 935–942.
Cline, T.J., Schindler, D.E., Hilborn, R., 2017, Fisheries portfolio diversification and turnover buffer Alaskan fishing communities from abrupt resource and market changes: Nature Communications, v: 8, 14042.
Brennan, S.R., Schindler, D.E., Cline, T.J., Walsworth, T.E., Buck, G., and Fernandez, D.P, 2019, Shifting habitat mosaics and fish production across river basins: Science, v. 364, p. 783–786.
**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.