Jeffrey Schaeffer (Former Employee)
Science and Products
Areas of Concern: Coordinated Support and Evaluation of the Maumee AOC
USGS scientists help support habitat assessment and restoration in the Maumee area of concern (AOC) to determine the extent to which beneficial uses are impaired and the types of management actions required to remediate and delist the AOC.
Seasonal patterns in hydrochemical mixing in three Great Lakes rivermouth ecosystems
Rivermouth ecosystems in the Laurentian Great Lakes represent complex hydrologic mixing zones where lake and river water combine to form biologically productive areas that are functionally similar to marine estuaries. As urban, industrial, shipping, and recreational centers, rivermouths are the focus of human interactions with the Great Lakes and...
Carlson-Mazur, Martha; Schaeffer, Jeff; Granneman, Jennifer E.; Goldstrohm, Natalie; Fitzpatrick, Faith A.; Larson, James H.; Reneau, Paul; Kowalski, Kurt P.; Seelbach, Paul W. Associations between cyanobacteria and indices of secondary production in the western basin of Lake Erie
Large lakes provide a variety of ecological services to surrounding cities and communities. Many of these services are supported by ecological processes that are threatened by the increasing prevalence of cyanobacterial blooms which occur as aquatic ecosystems experience cultural eutrophication. Over the past 10 yr, Lake Erie experienced...
Larson, James H.; Evans, Mary Anne; Kennedy, Robert J.; Bailey, Sean; Loftin, Keith A.; Laughrey, Zachary; Femmer, Robin; Schaeffer, Jeff; Richardson, William B.; Wynne, Timothy; Nelson, J. C.; Duris, Joseph W. Detecting spatial patterns of rivermouth processes using a geostatistical framework for near-real-time analysis
This paper proposes a geospatial analysis framework and software to interpret water-quality sampling data from towed undulating vehicles in near-real time. The framework includes data quality assurance and quality control processes, automated kriging interpolation along undulating paths, and local hotspot and cluster analyses. These methods are...
Xu, Wenzhao; Collingsworth, Paris D.; Bailey, Barbara; Carlson Mazur, Martha L.; Schaeffer, Jeff; Minsker, Barbara Understanding ecosystem services adoption by natural resource managers and research ecologists
The ecosystem services (ES) paradigm has gained much traction as a natural resource management approach due to its comprehensive nature and ability to provide quantitative tools to improve decision-making. However, it is still uncertain whether and how practitioners have adopted the ES paradigm into their work and how this aligns with resource...
Engel, Daniel; Evans, Mary Anne; Low, Bobbi S.; Schaeffer, Jeff Community stability within the St. Marys River fish community: Evidence from trawl surveys
A trawl survey was conducted in the Saint Marys River during 2010–2011 and we compared our results to a prior trawl survey conducted during 1979–1983 to look for long-term changes in the fish community, especially in terms of changes induced by invasive species. We found no substantive temporal differences in fish density, fish biomass, or fish...
Schaeffer, Jeffrey S.; Bowen, Anjanette K.; Fielder, David G. Understanding ecosystem services adoption by natural resource managers and research ecologists
The ecosystem services (ES) paradigm has gained much traction as a natural resource management approach due to its comprehensive nature and ability to provide quantitative tools to improve decision-making. However, it is still uncertain whether and how practitioners have adopted the ES paradigm into their work and how this aligns with resource...
Engel, Daniel; Evans, Mary Anne; Low, Bobbi S.; Schaeffer, Jeff Spatial variation in biofouling of a unionid mussel (Lampsilis siliquoidea) across the western basin of Lake Erie
Invasion of North American waters by nonnative Dreissena polymorpha and D. rostriformis bugensishas resulted in declines of the Unionidae family of native North American mussels. Dreissenid mussels biofoul unionid mussels in large numbers and interfere with unionid movement, their acquisition of food, and the native mussels' ability...
Larson, James H.; Evans, Mary Anne; Richardson, William B.; Schaeffer, Jeff; Nelson, John Measuring spatial variation in secondary production and food quality using a common consumer approach in Lake Erie
Lake Erie is a large lake straddling the border of the U.S. and Canada that has become increasingly eutrophic in recent years. Eutrophication is particularly focused in the shallow western basin. The western basin of Lake Erie is hydrodynamically similar to a large estuary, with riverine inputs from the Detroit and Maumee Rivers mixing together...
Larson, James H.; Richardson, William B.; Evans, Mary Anne; Schaeffer, Jeff; Wynne, Timothy; Bartsch, Michelle; Bartsch, Lynn; Nelson, J. C.; Vallazza, Jon M. A spatial classification and database for management, research, and policy making: The Great Lakes aquatic habitat framework
Managing the world's largest and most complex freshwater ecosystem, the Laurentian Great Lakes, requires a spatially hierarchical basin-wide database of ecological and socioeconomic information that is comparable across the region. To meet such a need, we developed a spatial classification framework and database — Great Lakes Aquatic Habitat...
Wang, Lizhu; Riseng, Catherine M.; Mason, Lacey; Werhrly, Kevin; Rutherford, Edward; McKenna, James E.; Castiglione, Chris; Johnson, Lucinda B.; Infante, Dana M.; Sowa, Scott P.; Robertson, Mike; Schaeffer, Jeff; Khoury, Mary; Gaiot, John; Hollenhurst, Tom; Brooks, Colin N.; Coscarelli, Mark Designing long-term fish community assessments in connecting channels: Lessons from the Saint Marys River
Long-term surveys are useful in understanding trends in connecting channel fish communities; a gill net assessment in the Saint Marys River performed periodically since 1975 is the most comprehensive connecting channels sampling program within the Laurentian Great Lakes. We assessed efficiency of that survey, with intent to inform development of...
Schaeffer, Jeff; Rogers, Mark W.; Fielder, David G.; Godby, Neal; Bowen, Anjanette K.; O'Connor, Lisa; Parrish, Josh; Greenwood, Susan; Chong, Stephen; Wright, Greg Angler-caught piscivore diets reflect fish community changes in Lake Huron
Examination of angler-caught piscivore stomachs revealed that Lake Trout Salvelinus namaycush, Chinook Salmon Oncorhynchus tshawytscha, and Walleyes Sander vitreus altered theirdiets in response to unprecedented declines in Lake Huron's main-basin prey fish community.Diets varied by...
Roseman, Edward F.; Schaeffer, Jeff; Bright, Ethan; Fielder, David G. Status and trends of pelagic prey fishes in Lake Huron, 2012
The USGS Great Lakes Science Center (GLSC) conducted acoustic/midwater trawl surveys of Lake Huron during 1997 and annually during 2004-2012. The 2012 survey was conducted during September and October, and included transects in Lake Huron’s Main Basin, Georgian Bay, and North Channel. Pelagic fish density (638 fish/ha) was lower in 2012 compared...
Warner, David M.; O'Brien, Timothy P.; Farha, Steve A.; Schaeffer, Jeff; Lenart, Stephen
Schaeffer to present at Michigan Wild Rice Summit
Identifying Tribal Research Priorities in the Great Lakes.
USGS to facilitate workshop in support of EPA’s Great Lakes Area of Concern program
Priorities set by this group will guide funding decicsionsj for years to come.
GLSC Scientists participate in Great Lakes Coastal Wetland Monitoring Program Planning
Planning Begins for the 2019 Field Season.