Patrick M Kocovsky
I am the Aquatic Invasive Species Program Manager within the Biological Threats and Invasive Species Research Program in the Ecosystems Mission Area.
I administer the USGS’ national research program on Aquatic Invasive Species. Our research foci include risk assessment, early detection and rapid response, and developing and evaluating deterrents and control methods for aquatic invasive species.
Education and Certifications
BS in Fishery Biology, magna cum laude, Colorado State, 1993
MS in Wildlife and Fisheries Science, Penn State, 1999
PhD in Wildlife and Fisheries Science, Penn State, 2004
Post-doc with USGS Northern Appalachian Research Lab on suitability of Susquehanna River tributaries for restoration of anadromous alosines and catadromous American Eel.
Science and Products
Invasive Species We Study: Invasive Carp
Bighead, black, grass, and silver carp, which are native to China, were originally stocked in aquaculture facilities to control algae, snails, and vegetation. These species escaped during flood events and are now established throughout the lower and middle Mississippi River Basins and some of its large tributaries where they damage ecosystems and harm economies. Grass carp are also reproducing in...
Invasive Species We Study: Sea Lamprey
The parasitic sea lamprey invaded the Great Lakes in the mid-20th Century devastating valuable native fisheries and coastal economies. The USGS’ Upper Midwest Environmental Sciences Center and the Great Lakes Science Center’s Hammond Bay Biological Station, in collaboration with the Great Lakes Fishery Commission, have been and continue to lead research on sea lamprey control, providing the...
Invasive Plants We Study: Brazilian Waterweed
Brazilian waterweed is an invasive aquatic plant.
Invasive Species We Study: Green Crab
European green crabs are one of the most widespread invasive marine species on the planet. Where they are abundant, green crabs outcompete other native shellfish. They are voracious eaters and a major predator of clams, mussels, and oysters. They also actively disturb bed sediments, leading to the loss of the eelgrass that serves as essential habitat for Dungeness crab and Pacific salmon. USGS is...
Invasive Species We Study: Lionfish
Lionfishes ( Pterois volitans and P. miles ) have established self-sustaining populations and spread throughout the Western North Atlantic, Caribbean Sea, and Gulf of Mexico. Although there are reports of lionfish sightings from decades past, the species have considerably increased in numbers and spread since 2000. The remarkable speed with which lionfishes have invaded the region is unprecedented...
Invasive Species We Study: Invasive Mussels
Invasive zebra and quagga mussels (collectively called dreissenid mussels) have significant ecological and economic effects. Dreissenids negatively affect industrial and municipal infrastructure, recreational water users, and they severely alter aquatic ecosystems by consuming algae and plankton. USGS has been conducting research on rapid response and control of dreissenid mussels in the Great...
Invasive Carp Integrated Control and Containment: Development of Monitoring and Response Methodologies, and Implementation of an Adaptive Management Framework to Work Towards Eradication of Grass Carp in Lake Erie
The US Geological Survey is studying life history and habitats of invasive Grass Carp with a goal of developing strategies and tactics to greatly reduce or possibly eradicate Grass Carp from Lake Erie.
Understanding How Climate Change Will Impact Aquatic Food Webs in the Great Lakes
This project addressed regional climate change effects on aquatic food webs in the Great Lakes. We sought insights by examining Lake Erie as a representative system with a high level of anthropogenic impacts, strong nutrient gradients, seasonal hypoxia, and spatial overlap of cold- and cool-water fish guilds. In Lake Erie and in large embayments throughout the Great Lakes basin, this situation is
Filter Total Items: 13
Daily ages of young-of-year Silver Chub from western Lake Erie, 2017-2018
Daily ages of young-of-year Silver Chub were estimated from counts of rings in lapilli otoliths. Lapilli were mounted to glass slides with thermoplastic cement and sanded to the core with 2000 grit sandpaper to expose daily rings. To improve clarity, sanded otoliths were polished with 0.3 μm alumina powder and a polishing cloth prior to viewing. To estimate daily age, counts of rings in otoliths w
Grass Carp (Ctenopharyngodon idella) egg capture data from tributaries to western Lake Erie, 2015-2020
The data includes dates, places, and times of sampling events for eggs and larvae of invasive Grass Carp (Ctenopharyngodon idella) in tributaries to Lake Erie between 2015 and 2020. Reference data on locations and dates sampled, gears used, and effort are included. Developmental stages for a subset of undamaged, fertilized eggs are provided. Tables include common fields to allow for integration in
Historical Length, Weight, and Fecundity of Silver Chub (Macrhybopsis storeriana) in Western Lake Erie
This data set provides a table of length, weight, sex, and estimated fecundity of Silver Chub Macrhybopsis storeriana in western Lake Erie from 1979 through 1987. These data are potentially useful to those studying recovery and restoration of Silver Chub in Lake Erie. These data were collected as part of routine trawl surveys in western Lake Erie. Other data associated with these data can be found
Hydroacoustic data from central Lake Erie, 2020
Hydroacoustic estimates of fish density are used for fisheries management in central Lake Erie. Hydroacoustic data were collected along 8, randomly-selected, 5-kilometer transects and three transects between the US shore and the international border in central Lake Erie in July 2020. Software-generated raw variables used for calculating estimates of hydroacoustic fish densities are presented here.
Effects of pulse duration on common hydroacoustic measures in Lake Erie in 2011-2012 and Ohio Reservoirs in 2017
Hydroacoustics is a common sampling tool in freshwater and marine ecosystems, yet the full potential of this tool remains restricted, owing to an incomplete understanding of the influence of many data collection settings. In particular, investigation into the effects of the pulse duration setting on common hydroacoustic measures remains limited. Hydroacoustic theory suggests that pulse duration ca
Development of an age estimation method for Grass Carp from North America
The development of a reliable method of age estimation for Grass Carp is necessary for the successful management of this invasive species. Multiple federal and state agencies with assistance from commercial fishers collected adult Grass Carp from 2012 to 2018. Ossified parts were collected from these fish, and age estimates from them were compared to develop an age estimation method. Here we provi
Inter-vessel comparison of hydroacoustic fish density in central Lake Erie, 2014
Hydroacoustic estimates of fish density are used for fisheries management in central Lake Erie. Data are sometimes collected from multiple vessels, raising the question of comparability of data collected among vessels. Hydroacoustic data were collected along three cross-lake transects in central Lake Erie in July, 2014 from three different vessels using similar equipment. Several variables derived
Hydroacoustic data from central Lake Erie, 2010-2019
Hydroacoustic estimates of fish density are used for fisheries management in central Lake Erie. Hydroacoustic data were collected along up to four cross-lake transects in central Lake Erie July 2010 through July 2019. Software-generated raw variables used for calculating estimates of hydroacoustic fish densities are presented here.
Developmental Stages of Grass Carp (Ctenopharyngodon idella) eggs in the Sandusky River (ver. 3.0, July 2020)
Grass Carp Ctenopharyngodon idella was imported to the United States in the 1960s for research into its usefulness as a biocontrol agent for nuisance aquatic vegetation. Escapees and intentionally stocked individuals founded wild, spawning populations in the Mississippi River and tributaries to the Laurentian Great Lakes. USGS-led research on the Sandusky River, a tributary to Lake Erie, demonstra
USGS Lake Erie East Harbor bottom trawl data series, 1961-2011 (ver. 2.0, March 2020)
The USGS Lake Erie Biological Station?s East Harbor sampling program began in 1961 with the commissioning of the research vessel Musky II. It is the longest known continuous trawl survey in Lake Erie. In addition to spanning over 50 years, the data series is unique for three prominent design elements: 1) sampling was conducted at three depth strata; 2) replicate trawl samples were collected at eac
Developmental Stages of Grass Carp (Ctenopharyngodon idella) eggs in the Sandusky River in 2017
Grass Carp Ctenopharyngodon idella was imported to the United States in the 1960s for research into its usefulness as a biocontrol agent for nuisance aquatic vegetation. Escapees and intentionally stocked individuals founded wild, spawning populations in the Mississippi River and tributaries to the Laurentian Great Lakes. USGS-led research on the Sandusky River, a tributary to Lake Erie, demonstra
Stable Isotopes of Silver Chub, Dreissenid mussels, and Hexagenia spp. Mayflies from Western Lake Erie, 2014
This table contains Carbon and Nitrogen stable isotope data for Silver Chub (Macrhybopsis storeriana), dreissenid mussels, and Hexagenia spp. mayflies from western Lake Erie in 2014. Samples were collected between May and September 2014 as part of both routine monitoring and a lake-wide coordinated monitoring effort. Silver Chub were collected in trawls; Hexagenia and Dreissenids were captured in
Filter Total Items: 56
Reproducing age variability in grass carp egg samples from the lower Sandusky River, Ohio, USA, using an egg-drift model
Invasive grass carp (Ctenopharyngodon idella) are currently reproducing in several tributaries to Lake Erie and threatening the Great Lakes ecosystem and fisheries. Grass carp are pelagic river spawners whose fertilized eggs drift downstream from the spawning site, developing as they drift. Variability in spawning time and location together with nonuniform velocities in natural rivers leads to egg
Authors
David T. Soong, P. Ryan Jackson, Patrick M. Kočovský, Lori Morrison, Tatiana Garcia, Santiago Santacruz, Cindy Chen, Zhenduo Zhu, Holly Susan Embke
Zebra and Quagga mussels in the United States—Dreissenid mussel research by the U.S. Geological Survey
The U.S. Geological Survey (USGS) delivers high-quality data, technologies, and decision-support tools to help managers both reduce existing populations and control the spread of dreissenid mussels. The USGS researches ecology, biology, risk assessment, and early detection and rapid response methods; provides decision support; and develops and tests control measures.
Authors
Cayla R. Morningstar, Patrick M. Kočovský, Michael E. Colvin, Timothy D. Counihan, Wesley M. Daniel, Peter C. Esselman, Cathy A. Richter, Adam Sepulveda, Diane L. Waller
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Columbia Environmental Research Center, Great Lakes Science Center, Northern Rocky Mountain Science Center, Upper Midwest Environmental Sciences Center, Western Fisheries Research Center, Wetland and Aquatic Research Center
Reproduction of grass carp (Ctenopharyngodon idella) in the Maumee River, Ohio: Part 1—Spawning area identification using bidirectional drift modeling
Control of invasive grass carp (Ctenopharyngodon idella) populations in the Western Lake Erie Basin merits adaptive management guided by the best available science. Presently (2024), capture of mature grass carp in rivers during spawning season is most efficient, so knowing when and where grass carp are spawning is essential information for natural resource agencies. Using bidirectional drift mode
Authors
P. Ryan Jackson, Charles V. Cigrand, Patrick M. Kočovský, Nicole R. King, Alan Kasprak, Evan M. Lindroth, Henry F. Doyle, Song S. Qian, Christine M. Mayer
Invasive species research—Science for prevention, detection, containment, and control
IntroductionInvasive species research within the U.S. Geological Survey’s (USGS) Ecosystems Mission Area focuses on invasive plants, animals, and pathogens throughout the United States. USGS scientists provide science support to help solve the problems posed by these nonnative species while working with partners in the U.S. Department of the Interior (DOI), other Federal, State, and Territorial ag
Authors
Paul J. Heimowitz, Patrick M. Kočovský, James J. English
Assessing the probability of grass carp (Ctenopharyngodon idella) spawning in the Sandusky River using discharge and water temperature
Grass carp (Ctenopharyngodon idella, Val.) is an invasive species in the Laurentian Great Lakes region with the potential for damaging the lake ecosystem and harming the region's economy. Grass carp spawning was documented in the Sandusky River, Ohio, in 2015 through targeted egg sampling. Continued egg sampling in the Sandusky River suggested that grass carp spawning is related to discharge and w
Authors
Sabrina Jaffe, Song S. Qian, Christine M. Mayer, Patrick M. Kočovský, Anarita Gouveia
Assessing potential spawning locations of Silver Chub in Lake Erie
ObjectiveSilver Chub Macrhybopsis storeriana, a predominately riverine species throughout its native range, exists within Lake Erie as the only known lake population. Its population declined in the 1950s and never fully recovered. Canada has listed Silver Chub in the Great Lakes–St. Lawrence River as endangered and has initiated a recovery plan that recognized the identification of spawning areas
Authors
Jorden R. McKenna, Anjanette Bowen, John R. Farver, James M. Long, Jeffrey G. Miner, Nathan D. Stott, Patrick M. Kočovský
Avoiding a macabre future for Macrhybopsis: A special section on improving management and conservation of chubs
No abstract available.
Authors
Joshuah S. Perkin, Shannon K. Brewer, Anthony A. Echelle, Patrick M. Kočovský
Genetic structure of the Silver Chub indicates distinctiveness of Lake Erie population
ObjectiveSilver Chub Macrhybopsis storeriana is a small riverine minnow endemic to North American fresh waters. Its range extends from the southern USA to southcentral Canada; the latter includes a rare lacustrine population in Lake Erie. Anthropogenic activities pose an immediate threat to several Silver Chub populations, currently categorized from special concern to threatened at the state level
Authors
Ahmed Elbassiouny, Joao Pedro Fontenelle, Patrick M. Kočovský, Nicholas E. Mandrak, Nathan R Lovejoy
Why are larger fish farther upstream? Testing multiple hypotheses using Silver Chub in two Midwestern United States riverscapes
ObjectiveThree competing hypotheses might explain the widely documented intrapopulation larger-fish-upstream phenomenon. The age-phased recruitment hypothesis posits that fish spawn downstream and move upstream as they age and grow, the static population with growth and mortality gradients hypothesis posits that fish spawn throughout a riverscape and growth is greater upstream while recruitment is
Authors
Joshuah S. Perkin, Patrick M. Kočovský, Zachary D Steffensmeier, Keith B. Gido
Assessment of three methods to evaluate the distribution of submersed aquatic vegetation in western Lake Erie
Submersed aquatic vegetation (SAV) plays an important role in ecosystems. Inventories of SAV spatial distribution and composition are important for monitoring changes in SAV. In this study, we compared three common SAV sampling methods to quantify SAV in western Lake Erie. Aerial imagery of near-shore areas in western Lake Erie was classified using object-based image analysis (OBIA) and evaluated
Authors
Nicole R. King, Jenny L. Hanson, Travis J. Harrison, Patrick M. Kočovský, Christine M. Mayer
A restructured Bayesian approach to estimate the abundance of a rare and invasive fish
Quantifying invasive species abundance informs management and control strategies. However, estimating abundance can be challenging, particularly when dealing with rare species early in the invasion process. Data generated from control strategies, such as removing invasive species, are usually not suited to conventional statistical modelling approaches. Hence, we developed a Bayesian model using da
Authors
Ana R. Gouveia, S. S. Qian, C. A. Mayer, J. A. Smith, J. Bossenbroek, W. D. Hintz, R. Mapes, E. Weimer, J. Navarro, J. M. Dettmers, R. Young, J. T. Buszkiewicz, Patrick M. Kočovský
Using the gut microbiome to assess stocking efforts of the endangered Pallid Sturgeon, Scaphirhynchus albus
The endangered Pallid Sturgeon, Scaphirhynchus albus, has been actively managed to prevent population declines, including stocking of hatchery-raised fish. The gut microbiome plays an innate role in an organism’s absorption of nutrients by increasing nutrient availability and can provide new insights for Pallid Sturgeon management. In this study, the Pallid Sturgeon’s microbiome is dominated by th
Authors
Sarah Gaughan, John A. Kyndt, Justin D. Haas, Kirk D. Steffensen, Patrick M. Kočovský, Kevin L. Pope
Science and Products
Invasive Species We Study: Invasive Carp
Bighead, black, grass, and silver carp, which are native to China, were originally stocked in aquaculture facilities to control algae, snails, and vegetation. These species escaped during flood events and are now established throughout the lower and middle Mississippi River Basins and some of its large tributaries where they damage ecosystems and harm economies. Grass carp are also reproducing in...
Invasive Species We Study: Sea Lamprey
The parasitic sea lamprey invaded the Great Lakes in the mid-20th Century devastating valuable native fisheries and coastal economies. The USGS’ Upper Midwest Environmental Sciences Center and the Great Lakes Science Center’s Hammond Bay Biological Station, in collaboration with the Great Lakes Fishery Commission, have been and continue to lead research on sea lamprey control, providing the...
Invasive Plants We Study: Brazilian Waterweed
Brazilian waterweed is an invasive aquatic plant.
Invasive Species We Study: Green Crab
European green crabs are one of the most widespread invasive marine species on the planet. Where they are abundant, green crabs outcompete other native shellfish. They are voracious eaters and a major predator of clams, mussels, and oysters. They also actively disturb bed sediments, leading to the loss of the eelgrass that serves as essential habitat for Dungeness crab and Pacific salmon. USGS is...
Invasive Species We Study: Lionfish
Lionfishes ( Pterois volitans and P. miles ) have established self-sustaining populations and spread throughout the Western North Atlantic, Caribbean Sea, and Gulf of Mexico. Although there are reports of lionfish sightings from decades past, the species have considerably increased in numbers and spread since 2000. The remarkable speed with which lionfishes have invaded the region is unprecedented...
Invasive Species We Study: Invasive Mussels
Invasive zebra and quagga mussels (collectively called dreissenid mussels) have significant ecological and economic effects. Dreissenids negatively affect industrial and municipal infrastructure, recreational water users, and they severely alter aquatic ecosystems by consuming algae and plankton. USGS has been conducting research on rapid response and control of dreissenid mussels in the Great...
Invasive Carp Integrated Control and Containment: Development of Monitoring and Response Methodologies, and Implementation of an Adaptive Management Framework to Work Towards Eradication of Grass Carp in Lake Erie
The US Geological Survey is studying life history and habitats of invasive Grass Carp with a goal of developing strategies and tactics to greatly reduce or possibly eradicate Grass Carp from Lake Erie.
Understanding How Climate Change Will Impact Aquatic Food Webs in the Great Lakes
This project addressed regional climate change effects on aquatic food webs in the Great Lakes. We sought insights by examining Lake Erie as a representative system with a high level of anthropogenic impacts, strong nutrient gradients, seasonal hypoxia, and spatial overlap of cold- and cool-water fish guilds. In Lake Erie and in large embayments throughout the Great Lakes basin, this situation is
Filter Total Items: 13
Daily ages of young-of-year Silver Chub from western Lake Erie, 2017-2018
Daily ages of young-of-year Silver Chub were estimated from counts of rings in lapilli otoliths. Lapilli were mounted to glass slides with thermoplastic cement and sanded to the core with 2000 grit sandpaper to expose daily rings. To improve clarity, sanded otoliths were polished with 0.3 μm alumina powder and a polishing cloth prior to viewing. To estimate daily age, counts of rings in otoliths w
Grass Carp (Ctenopharyngodon idella) egg capture data from tributaries to western Lake Erie, 2015-2020
The data includes dates, places, and times of sampling events for eggs and larvae of invasive Grass Carp (Ctenopharyngodon idella) in tributaries to Lake Erie between 2015 and 2020. Reference data on locations and dates sampled, gears used, and effort are included. Developmental stages for a subset of undamaged, fertilized eggs are provided. Tables include common fields to allow for integration in
Historical Length, Weight, and Fecundity of Silver Chub (Macrhybopsis storeriana) in Western Lake Erie
This data set provides a table of length, weight, sex, and estimated fecundity of Silver Chub Macrhybopsis storeriana in western Lake Erie from 1979 through 1987. These data are potentially useful to those studying recovery and restoration of Silver Chub in Lake Erie. These data were collected as part of routine trawl surveys in western Lake Erie. Other data associated with these data can be found
Hydroacoustic data from central Lake Erie, 2020
Hydroacoustic estimates of fish density are used for fisheries management in central Lake Erie. Hydroacoustic data were collected along 8, randomly-selected, 5-kilometer transects and three transects between the US shore and the international border in central Lake Erie in July 2020. Software-generated raw variables used for calculating estimates of hydroacoustic fish densities are presented here.
Effects of pulse duration on common hydroacoustic measures in Lake Erie in 2011-2012 and Ohio Reservoirs in 2017
Hydroacoustics is a common sampling tool in freshwater and marine ecosystems, yet the full potential of this tool remains restricted, owing to an incomplete understanding of the influence of many data collection settings. In particular, investigation into the effects of the pulse duration setting on common hydroacoustic measures remains limited. Hydroacoustic theory suggests that pulse duration ca
Development of an age estimation method for Grass Carp from North America
The development of a reliable method of age estimation for Grass Carp is necessary for the successful management of this invasive species. Multiple federal and state agencies with assistance from commercial fishers collected adult Grass Carp from 2012 to 2018. Ossified parts were collected from these fish, and age estimates from them were compared to develop an age estimation method. Here we provi
Inter-vessel comparison of hydroacoustic fish density in central Lake Erie, 2014
Hydroacoustic estimates of fish density are used for fisheries management in central Lake Erie. Data are sometimes collected from multiple vessels, raising the question of comparability of data collected among vessels. Hydroacoustic data were collected along three cross-lake transects in central Lake Erie in July, 2014 from three different vessels using similar equipment. Several variables derived
Hydroacoustic data from central Lake Erie, 2010-2019
Hydroacoustic estimates of fish density are used for fisheries management in central Lake Erie. Hydroacoustic data were collected along up to four cross-lake transects in central Lake Erie July 2010 through July 2019. Software-generated raw variables used for calculating estimates of hydroacoustic fish densities are presented here.
Developmental Stages of Grass Carp (Ctenopharyngodon idella) eggs in the Sandusky River (ver. 3.0, July 2020)
Grass Carp Ctenopharyngodon idella was imported to the United States in the 1960s for research into its usefulness as a biocontrol agent for nuisance aquatic vegetation. Escapees and intentionally stocked individuals founded wild, spawning populations in the Mississippi River and tributaries to the Laurentian Great Lakes. USGS-led research on the Sandusky River, a tributary to Lake Erie, demonstra
USGS Lake Erie East Harbor bottom trawl data series, 1961-2011 (ver. 2.0, March 2020)
The USGS Lake Erie Biological Station?s East Harbor sampling program began in 1961 with the commissioning of the research vessel Musky II. It is the longest known continuous trawl survey in Lake Erie. In addition to spanning over 50 years, the data series is unique for three prominent design elements: 1) sampling was conducted at three depth strata; 2) replicate trawl samples were collected at eac
Developmental Stages of Grass Carp (Ctenopharyngodon idella) eggs in the Sandusky River in 2017
Grass Carp Ctenopharyngodon idella was imported to the United States in the 1960s for research into its usefulness as a biocontrol agent for nuisance aquatic vegetation. Escapees and intentionally stocked individuals founded wild, spawning populations in the Mississippi River and tributaries to the Laurentian Great Lakes. USGS-led research on the Sandusky River, a tributary to Lake Erie, demonstra
Stable Isotopes of Silver Chub, Dreissenid mussels, and Hexagenia spp. Mayflies from Western Lake Erie, 2014
This table contains Carbon and Nitrogen stable isotope data for Silver Chub (Macrhybopsis storeriana), dreissenid mussels, and Hexagenia spp. mayflies from western Lake Erie in 2014. Samples were collected between May and September 2014 as part of both routine monitoring and a lake-wide coordinated monitoring effort. Silver Chub were collected in trawls; Hexagenia and Dreissenids were captured in
Filter Total Items: 56
Reproducing age variability in grass carp egg samples from the lower Sandusky River, Ohio, USA, using an egg-drift model
Invasive grass carp (Ctenopharyngodon idella) are currently reproducing in several tributaries to Lake Erie and threatening the Great Lakes ecosystem and fisheries. Grass carp are pelagic river spawners whose fertilized eggs drift downstream from the spawning site, developing as they drift. Variability in spawning time and location together with nonuniform velocities in natural rivers leads to egg
Authors
David T. Soong, P. Ryan Jackson, Patrick M. Kočovský, Lori Morrison, Tatiana Garcia, Santiago Santacruz, Cindy Chen, Zhenduo Zhu, Holly Susan Embke
Zebra and Quagga mussels in the United States—Dreissenid mussel research by the U.S. Geological Survey
The U.S. Geological Survey (USGS) delivers high-quality data, technologies, and decision-support tools to help managers both reduce existing populations and control the spread of dreissenid mussels. The USGS researches ecology, biology, risk assessment, and early detection and rapid response methods; provides decision support; and develops and tests control measures.
Authors
Cayla R. Morningstar, Patrick M. Kočovský, Michael E. Colvin, Timothy D. Counihan, Wesley M. Daniel, Peter C. Esselman, Cathy A. Richter, Adam Sepulveda, Diane L. Waller
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Columbia Environmental Research Center, Great Lakes Science Center, Northern Rocky Mountain Science Center, Upper Midwest Environmental Sciences Center, Western Fisheries Research Center, Wetland and Aquatic Research Center
Reproduction of grass carp (Ctenopharyngodon idella) in the Maumee River, Ohio: Part 1—Spawning area identification using bidirectional drift modeling
Control of invasive grass carp (Ctenopharyngodon idella) populations in the Western Lake Erie Basin merits adaptive management guided by the best available science. Presently (2024), capture of mature grass carp in rivers during spawning season is most efficient, so knowing when and where grass carp are spawning is essential information for natural resource agencies. Using bidirectional drift mode
Authors
P. Ryan Jackson, Charles V. Cigrand, Patrick M. Kočovský, Nicole R. King, Alan Kasprak, Evan M. Lindroth, Henry F. Doyle, Song S. Qian, Christine M. Mayer
Invasive species research—Science for prevention, detection, containment, and control
IntroductionInvasive species research within the U.S. Geological Survey’s (USGS) Ecosystems Mission Area focuses on invasive plants, animals, and pathogens throughout the United States. USGS scientists provide science support to help solve the problems posed by these nonnative species while working with partners in the U.S. Department of the Interior (DOI), other Federal, State, and Territorial ag
Authors
Paul J. Heimowitz, Patrick M. Kočovský, James J. English
Assessing the probability of grass carp (Ctenopharyngodon idella) spawning in the Sandusky River using discharge and water temperature
Grass carp (Ctenopharyngodon idella, Val.) is an invasive species in the Laurentian Great Lakes region with the potential for damaging the lake ecosystem and harming the region's economy. Grass carp spawning was documented in the Sandusky River, Ohio, in 2015 through targeted egg sampling. Continued egg sampling in the Sandusky River suggested that grass carp spawning is related to discharge and w
Authors
Sabrina Jaffe, Song S. Qian, Christine M. Mayer, Patrick M. Kočovský, Anarita Gouveia
Assessing potential spawning locations of Silver Chub in Lake Erie
ObjectiveSilver Chub Macrhybopsis storeriana, a predominately riverine species throughout its native range, exists within Lake Erie as the only known lake population. Its population declined in the 1950s and never fully recovered. Canada has listed Silver Chub in the Great Lakes–St. Lawrence River as endangered and has initiated a recovery plan that recognized the identification of spawning areas
Authors
Jorden R. McKenna, Anjanette Bowen, John R. Farver, James M. Long, Jeffrey G. Miner, Nathan D. Stott, Patrick M. Kočovský
Avoiding a macabre future for Macrhybopsis: A special section on improving management and conservation of chubs
No abstract available.
Authors
Joshuah S. Perkin, Shannon K. Brewer, Anthony A. Echelle, Patrick M. Kočovský
Genetic structure of the Silver Chub indicates distinctiveness of Lake Erie population
ObjectiveSilver Chub Macrhybopsis storeriana is a small riverine minnow endemic to North American fresh waters. Its range extends from the southern USA to southcentral Canada; the latter includes a rare lacustrine population in Lake Erie. Anthropogenic activities pose an immediate threat to several Silver Chub populations, currently categorized from special concern to threatened at the state level
Authors
Ahmed Elbassiouny, Joao Pedro Fontenelle, Patrick M. Kočovský, Nicholas E. Mandrak, Nathan R Lovejoy
Why are larger fish farther upstream? Testing multiple hypotheses using Silver Chub in two Midwestern United States riverscapes
ObjectiveThree competing hypotheses might explain the widely documented intrapopulation larger-fish-upstream phenomenon. The age-phased recruitment hypothesis posits that fish spawn downstream and move upstream as they age and grow, the static population with growth and mortality gradients hypothesis posits that fish spawn throughout a riverscape and growth is greater upstream while recruitment is
Authors
Joshuah S. Perkin, Patrick M. Kočovský, Zachary D Steffensmeier, Keith B. Gido
Assessment of three methods to evaluate the distribution of submersed aquatic vegetation in western Lake Erie
Submersed aquatic vegetation (SAV) plays an important role in ecosystems. Inventories of SAV spatial distribution and composition are important for monitoring changes in SAV. In this study, we compared three common SAV sampling methods to quantify SAV in western Lake Erie. Aerial imagery of near-shore areas in western Lake Erie was classified using object-based image analysis (OBIA) and evaluated
Authors
Nicole R. King, Jenny L. Hanson, Travis J. Harrison, Patrick M. Kočovský, Christine M. Mayer
A restructured Bayesian approach to estimate the abundance of a rare and invasive fish
Quantifying invasive species abundance informs management and control strategies. However, estimating abundance can be challenging, particularly when dealing with rare species early in the invasion process. Data generated from control strategies, such as removing invasive species, are usually not suited to conventional statistical modelling approaches. Hence, we developed a Bayesian model using da
Authors
Ana R. Gouveia, S. S. Qian, C. A. Mayer, J. A. Smith, J. Bossenbroek, W. D. Hintz, R. Mapes, E. Weimer, J. Navarro, J. M. Dettmers, R. Young, J. T. Buszkiewicz, Patrick M. Kočovský
Using the gut microbiome to assess stocking efforts of the endangered Pallid Sturgeon, Scaphirhynchus albus
The endangered Pallid Sturgeon, Scaphirhynchus albus, has been actively managed to prevent population declines, including stocking of hatchery-raised fish. The gut microbiome plays an innate role in an organism’s absorption of nutrients by increasing nutrient availability and can provide new insights for Pallid Sturgeon management. In this study, the Pallid Sturgeon’s microbiome is dominated by th
Authors
Sarah Gaughan, John A. Kyndt, Justin D. Haas, Kirk D. Steffensen, Patrick M. Kočovský, Kevin L. Pope