A dragonfly in the wetlands in Southeast/Central ND - Stutsman and Kidder counties, ND in grassland and on farms.
Johanna Kraus, PhD
Dr. Johanna M. Kraus is a Research Ecologist at the Columbia Environmental Research Center.
She studies effects of anthropogenic stressors on food webs, biodiversity and environmental health in aquatic and terrestrial ecosystems. She began her career with the USGS in 2011 researching how trace metals from acid rock drainage impact adult aquatic insect emergence and contaminant flux to terrestrial insectivores near mountain streams. Since then, her research has uncovered when and where contaminants may impact aquatic and terrestrial food webs using large empirical field studies, laboratory manipulations and conceptual modelling. Dr. Kraus received her B.A. in Biology from Brown University and Ph.D. in Biology from the University of Virginia.
Science and Products
Increased Mercury, Reduced Insect Diversity, and Food Web impacts from Historical Mercury Mining
U.S. Geological Survey scientists are seeking to understand the impacts of mercury mining on headwater streams, organisms, and food webs, focused on potential effects from historical mining in central Idaho. Mercury associated with mine waste can leave a legacy of contamination that continues to impact stream health in culturally and ecologically important headwater streams after mining activities...
Conceptual Model Developed to Understand Contaminant Pathways between Aquatic and Terrestrial Ecosystems
A conceptual model, based on contaminant properties and ecotoxicological principles, was developed to understand the transfer of contaminants from aquatic to terrestrial ecosystems and the effects of various classes of contaminants on terrestrial insectivores living near contaminated freshwaters.
Trace Metal Mobility in the Yellow Pine Mining District, Idaho
The study objective is to conduct an integrated, interdisciplinary study on source areas, biogeochemical transformations, and physical and biological pathways for trace metal transport in a tributary of the Snake River watershed, focusing on the Sugar Creek watershed. The historical Cinnabar mercury mine site is at the headwaters of Cinnabar Creek, a tributary to Sugar Creek. This integrated...
Aquatic Ecology and Contaminants
The Aquatic Ecology and Contaminants Team investigates critical ecological processes operating in aquatic and riparian ecosystems and how these processes are affected by human activities. We address questions through a combination of field studies, laboratory experiments, and modeling, while working at multiple levels of biological organization from cells through ecosystems. Topics include land...
Pesticides in the Prairie Pothole Region
Wetlands of the northern Great Plains are crucial feeding grounds for migrating birds and waterfowl embedded in an agricultural landscape. Land use and hydrology can affect adult aquatic insects – crucial prey for critically declining populations of insectivorous birds. Current studies focus on effects of current-use pesticides on adult aquatic insects to inform decision making about contaminants...
Effects of Contaminants on Linked Aquatic and Terrestrial Food Webs
Most aquatic insects live in fresh water as larvae and move to land as flying adults to complete their life cycle. Although often ignored, the emergence of adults can transfer the effects of contamination from aquatic to terrestrial ecosystems as the adults are eaten by predators such as spiders, birds, and bats.
A dragonfly in the wetlands in Southeast North Dakota.
A dragonfly in the wetlands in Southeast/Central ND - Stutsman and Kidder counties, ND in grassland and on farms.
A dragonfly on a stick
A dragonfly on a stick in the Prairie Pothole region of the U.S. This is one of the many insects studied during an investigation study of the effects of the Prairie Pothole Wetlands in the U.S.
A dragonfly on a stick in the Prairie Pothole region of the U.S. This is one of the many insects studied during an investigation study of the effects of the Prairie Pothole Wetlands in the U.S.
Mayfly in Idaho
A recently emerged mayfly collected downstream of the Cinnabar mercury mine site in central Idaho.
A recently emerged mayfly collected downstream of the Cinnabar mercury mine site in central Idaho.
USGS scientists samples the East Fork of the Upper Arkansas River
USGS Scientists study the effects of trace metal contamination on diets of stream fish. Vegetation surrounding this relatively pristine stream is dominated by deciduous willow, which are inhabited by riparian spiders that consume adult aquatic insects emerging from the stream. Regionally, streams are impacted by acid mine drainage and natural mineralization.
USGS Scientists study the effects of trace metal contamination on diets of stream fish. Vegetation surrounding this relatively pristine stream is dominated by deciduous willow, which are inhabited by riparian spiders that consume adult aquatic insects emerging from the stream. Regionally, streams are impacted by acid mine drainage and natural mineralization.
Science and Products
Increased Mercury, Reduced Insect Diversity, and Food Web impacts from Historical Mercury Mining
U.S. Geological Survey scientists are seeking to understand the impacts of mercury mining on headwater streams, organisms, and food webs, focused on potential effects from historical mining in central Idaho. Mercury associated with mine waste can leave a legacy of contamination that continues to impact stream health in culturally and ecologically important headwater streams after mining activities...
Conceptual Model Developed to Understand Contaminant Pathways between Aquatic and Terrestrial Ecosystems
A conceptual model, based on contaminant properties and ecotoxicological principles, was developed to understand the transfer of contaminants from aquatic to terrestrial ecosystems and the effects of various classes of contaminants on terrestrial insectivores living near contaminated freshwaters.
Trace Metal Mobility in the Yellow Pine Mining District, Idaho
The study objective is to conduct an integrated, interdisciplinary study on source areas, biogeochemical transformations, and physical and biological pathways for trace metal transport in a tributary of the Snake River watershed, focusing on the Sugar Creek watershed. The historical Cinnabar mercury mine site is at the headwaters of Cinnabar Creek, a tributary to Sugar Creek. This integrated...
Aquatic Ecology and Contaminants
The Aquatic Ecology and Contaminants Team investigates critical ecological processes operating in aquatic and riparian ecosystems and how these processes are affected by human activities. We address questions through a combination of field studies, laboratory experiments, and modeling, while working at multiple levels of biological organization from cells through ecosystems. Topics include land...
Pesticides in the Prairie Pothole Region
Wetlands of the northern Great Plains are crucial feeding grounds for migrating birds and waterfowl embedded in an agricultural landscape. Land use and hydrology can affect adult aquatic insects – crucial prey for critically declining populations of insectivorous birds. Current studies focus on effects of current-use pesticides on adult aquatic insects to inform decision making about contaminants...
Effects of Contaminants on Linked Aquatic and Terrestrial Food Webs
Most aquatic insects live in fresh water as larvae and move to land as flying adults to complete their life cycle. Although often ignored, the emergence of adults can transfer the effects of contamination from aquatic to terrestrial ecosystems as the adults are eaten by predators such as spiders, birds, and bats.
A dragonfly in the wetlands in Southeast North Dakota.
A dragonfly in the wetlands in Southeast/Central ND - Stutsman and Kidder counties, ND in grassland and on farms.
A dragonfly in the wetlands in Southeast/Central ND - Stutsman and Kidder counties, ND in grassland and on farms.
A dragonfly on a stick
A dragonfly on a stick in the Prairie Pothole region of the U.S. This is one of the many insects studied during an investigation study of the effects of the Prairie Pothole Wetlands in the U.S.
A dragonfly on a stick in the Prairie Pothole region of the U.S. This is one of the many insects studied during an investigation study of the effects of the Prairie Pothole Wetlands in the U.S.
Mayfly in Idaho
A recently emerged mayfly collected downstream of the Cinnabar mercury mine site in central Idaho.
A recently emerged mayfly collected downstream of the Cinnabar mercury mine site in central Idaho.
USGS scientists samples the East Fork of the Upper Arkansas River
USGS Scientists study the effects of trace metal contamination on diets of stream fish. Vegetation surrounding this relatively pristine stream is dominated by deciduous willow, which are inhabited by riparian spiders that consume adult aquatic insects emerging from the stream. Regionally, streams are impacted by acid mine drainage and natural mineralization.
USGS Scientists study the effects of trace metal contamination on diets of stream fish. Vegetation surrounding this relatively pristine stream is dominated by deciduous willow, which are inhabited by riparian spiders that consume adult aquatic insects emerging from the stream. Regionally, streams are impacted by acid mine drainage and natural mineralization.