EESC's Heather Walsh shows off the results of a fish dissection conducted as part of the 2023 Earth Day Celebration and Open House at the Leetown Research Laboratory.
Heather Walsh
Dr. Heather Walsh is a Research Fish Biologist that has been involved in research at the Eastern Ecological Science Center since 2006.
Dr. Walsh has focused on developing molecular techniques to better understand mechanisms associated with disease in wild fish. To serve this purpose, she has developed her skills in histopathology, in situ hybridization techniques, and laser capture microdissection. The use of these techniques has helped to understand disease observed during fish health assessments conducted in the Great Lakes and Chesapeake Bay (including the Susquehanna and Potomac River drainage). Much of her work has focused on fish species used as indicators of environmental contamination, including smallmouth bass, brown bullhead catfish, white suckers, and yellow perch. She also uses PCR, Sanger sequencing, Nanostring technology, and RNA-Seq to help identify parasites or pathogens, for transcript abundance analyses, and de novo transcriptome development.
Science and Products
New study highlights linkages among land use, water chemistry, and the health of Smallmouth Bass in the Susquehanna River watershed
Contaminants associated with agricultural and developed land uses may negatively affect SMB health and disease resistance in the Susquehanna River watershed.
A case study of temporal trends in risk factors associated with endocrine disruption in smallmouth bass
Issue The USGS has a long-term research effort that identified endocrine disruption in smallmouth bass (SMB) in the Chesapeake Bay watershed. Endocrine disruption can cause many changes in fish, including intersex characteristics where fish develop characteristics of the other sex, such as immature eggs forming in males. An overview by USGS of endocrine disruption in fish found the condition...
Fishing and Hunting Integrated Science Team
The Fishing and Hunting integrated science team focuses on contaminant and pathogen exposures in the environment that could impact the presence and vitality of fish and wildlife populations that drive commercial, recreational and subsistence activities such as hunting and fishing. If actual risks are identified this project will inform how to economically and effectively minimize risk by providing...
Fish dissection results
EESC's Heather Walsh shows off the results of a fish dissection conducted as part of the 2023 Earth Day Celebration and Open House at the Leetown Research Laboratory.
Early Morning Sunrise at the Fish Health Laboratory Reservoir
Beautiful, early morning sunrise of a reservoir located at the Fish Health Lab in Kearneysville, WV. This photo was taken during a bird walk to participate in the nationwide Christmas Bird Count conducted by eBird.
Beautiful, early morning sunrise of a reservoir located at the Fish Health Lab in Kearneysville, WV. This photo was taken during a bird walk to participate in the nationwide Christmas Bird Count conducted by eBird.
Taking a blood sample from the caudal vein of a smallmouth bass
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River. As part of our nonlethal sampling methods, blood/plasma can be analyzed for PFAS in smallmouth bass.
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River. As part of our nonlethal sampling methods, blood/plasma can be analyzed for PFAS in smallmouth bass.
Observing smallmouth bass gills for abnormalities
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River.
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River.
Panoramic View of the Leetown Trout Pond
A beautiful, sunny day with blue skies at the Leetown trout pond while on a birding excursion with the Potomac Valley Audubon Society. This trout pond plays an important role in the community and gives veterans and handicapped groups the chance to get outside and catch big trout! It also provides nourishing trout to the resident bald eagles.
A beautiful, sunny day with blue skies at the Leetown trout pond while on a birding excursion with the Potomac Valley Audubon Society. This trout pond plays an important role in the community and gives veterans and handicapped groups the chance to get outside and catch big trout! It also provides nourishing trout to the resident bald eagles.
Chesapeake Bay Land Use Map and Chart
Land use (2016) in the immediate (insert) and upstream catchments around the smallmouth bass, Antietam Creek – Potomac Mainstem collection site near Dargan, Maryland.
Land use (2016) in the immediate (insert) and upstream catchments around the smallmouth bass, Antietam Creek – Potomac Mainstem collection site near Dargan, Maryland.
Chart of changes in smallmouth bass
Annual and seasonal changes in plasma vitellogenin (Vtg) and hepatic vitellogenin (vtg) gene transcripts in A) female and B) male smallmouth bass. C) Prevalence and severity of testicular oocytes (TO) in male smallmouth bass.
Annual and seasonal changes in plasma vitellogenin (Vtg) and hepatic vitellogenin (vtg) gene transcripts in A) female and B) male smallmouth bass. C) Prevalence and severity of testicular oocytes (TO) in male smallmouth bass.
Chart of concentrations of three of the most detected pesticides in Dargan, MD
Concentrations of three of the most detected pesticides (simazine, atrazine, and metolachlor) sampled near the confluence of Antietam Creek and the Potomac River in Dargan, Maryland, 2013-2019. Dots represent smallmouth bass sampling dates.
Concentrations of three of the most detected pesticides (simazine, atrazine, and metolachlor) sampled near the confluence of Antietam Creek and the Potomac River in Dargan, Maryland, 2013-2019. Dots represent smallmouth bass sampling dates.
Muskellunge used in a catch and release study on angling mortality
Photo of a 45" muskellunge used in a catch and release study on angling mortality during warmer summer conditions. This study was led by Kyle Hartman from West Virginia University and his graduate student, Taylor Booth.
Photo of a 45" muskellunge used in a catch and release study on angling mortality during warmer summer conditions. This study was led by Kyle Hartman from West Virginia University and his graduate student, Taylor Booth.
Histology lab at the Fish Health Laboratory prior to renovation
Histology laboratory with coverslipping area to the left. Coverslipping is when tissues cross-sections that are dried onto slides are coverslipped with a thin piece of glass. In the center is the file/record keeping area where every sample was logged and given a study number.
Histology laboratory with coverslipping area to the left. Coverslipping is when tissues cross-sections that are dried onto slides are coverslipped with a thin piece of glass. In the center is the file/record keeping area where every sample was logged and given a study number.
USGS scientist processing fish for fish health assessments
USGS scientist Vicki Blazer obtaining a blood sample and performing fish necropsy for fish health assessments
USGS scientist Vicki Blazer obtaining a blood sample and performing fish necropsy for fish health assessments
Science and Products
New study highlights linkages among land use, water chemistry, and the health of Smallmouth Bass in the Susquehanna River watershed
Contaminants associated with agricultural and developed land uses may negatively affect SMB health and disease resistance in the Susquehanna River watershed.
A case study of temporal trends in risk factors associated with endocrine disruption in smallmouth bass
Issue The USGS has a long-term research effort that identified endocrine disruption in smallmouth bass (SMB) in the Chesapeake Bay watershed. Endocrine disruption can cause many changes in fish, including intersex characteristics where fish develop characteristics of the other sex, such as immature eggs forming in males. An overview by USGS of endocrine disruption in fish found the condition...
Fishing and Hunting Integrated Science Team
The Fishing and Hunting integrated science team focuses on contaminant and pathogen exposures in the environment that could impact the presence and vitality of fish and wildlife populations that drive commercial, recreational and subsistence activities such as hunting and fishing. If actual risks are identified this project will inform how to economically and effectively minimize risk by providing...
Fish dissection results
EESC's Heather Walsh shows off the results of a fish dissection conducted as part of the 2023 Earth Day Celebration and Open House at the Leetown Research Laboratory.
EESC's Heather Walsh shows off the results of a fish dissection conducted as part of the 2023 Earth Day Celebration and Open House at the Leetown Research Laboratory.
Early Morning Sunrise at the Fish Health Laboratory Reservoir
Beautiful, early morning sunrise of a reservoir located at the Fish Health Lab in Kearneysville, WV. This photo was taken during a bird walk to participate in the nationwide Christmas Bird Count conducted by eBird.
Beautiful, early morning sunrise of a reservoir located at the Fish Health Lab in Kearneysville, WV. This photo was taken during a bird walk to participate in the nationwide Christmas Bird Count conducted by eBird.
Taking a blood sample from the caudal vein of a smallmouth bass
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River. As part of our nonlethal sampling methods, blood/plasma can be analyzed for PFAS in smallmouth bass.
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River. As part of our nonlethal sampling methods, blood/plasma can be analyzed for PFAS in smallmouth bass.
Observing smallmouth bass gills for abnormalities
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River.
Nonlethal smallmouth bass sampling is being done to address health concerns and population declines that may be associated with polyfluoroalkyl substances (PFAS) in the upper Potomac River.
Panoramic View of the Leetown Trout Pond
A beautiful, sunny day with blue skies at the Leetown trout pond while on a birding excursion with the Potomac Valley Audubon Society. This trout pond plays an important role in the community and gives veterans and handicapped groups the chance to get outside and catch big trout! It also provides nourishing trout to the resident bald eagles.
A beautiful, sunny day with blue skies at the Leetown trout pond while on a birding excursion with the Potomac Valley Audubon Society. This trout pond plays an important role in the community and gives veterans and handicapped groups the chance to get outside and catch big trout! It also provides nourishing trout to the resident bald eagles.
Chesapeake Bay Land Use Map and Chart
Land use (2016) in the immediate (insert) and upstream catchments around the smallmouth bass, Antietam Creek – Potomac Mainstem collection site near Dargan, Maryland.
Land use (2016) in the immediate (insert) and upstream catchments around the smallmouth bass, Antietam Creek – Potomac Mainstem collection site near Dargan, Maryland.
Chart of changes in smallmouth bass
Annual and seasonal changes in plasma vitellogenin (Vtg) and hepatic vitellogenin (vtg) gene transcripts in A) female and B) male smallmouth bass. C) Prevalence and severity of testicular oocytes (TO) in male smallmouth bass.
Annual and seasonal changes in plasma vitellogenin (Vtg) and hepatic vitellogenin (vtg) gene transcripts in A) female and B) male smallmouth bass. C) Prevalence and severity of testicular oocytes (TO) in male smallmouth bass.
Chart of concentrations of three of the most detected pesticides in Dargan, MD
Concentrations of three of the most detected pesticides (simazine, atrazine, and metolachlor) sampled near the confluence of Antietam Creek and the Potomac River in Dargan, Maryland, 2013-2019. Dots represent smallmouth bass sampling dates.
Concentrations of three of the most detected pesticides (simazine, atrazine, and metolachlor) sampled near the confluence of Antietam Creek and the Potomac River in Dargan, Maryland, 2013-2019. Dots represent smallmouth bass sampling dates.
Muskellunge used in a catch and release study on angling mortality
Photo of a 45" muskellunge used in a catch and release study on angling mortality during warmer summer conditions. This study was led by Kyle Hartman from West Virginia University and his graduate student, Taylor Booth.
Photo of a 45" muskellunge used in a catch and release study on angling mortality during warmer summer conditions. This study was led by Kyle Hartman from West Virginia University and his graduate student, Taylor Booth.
Histology lab at the Fish Health Laboratory prior to renovation
Histology laboratory with coverslipping area to the left. Coverslipping is when tissues cross-sections that are dried onto slides are coverslipped with a thin piece of glass. In the center is the file/record keeping area where every sample was logged and given a study number.
Histology laboratory with coverslipping area to the left. Coverslipping is when tissues cross-sections that are dried onto slides are coverslipped with a thin piece of glass. In the center is the file/record keeping area where every sample was logged and given a study number.
USGS scientist processing fish for fish health assessments
USGS scientist Vicki Blazer obtaining a blood sample and performing fish necropsy for fish health assessments
USGS scientist Vicki Blazer obtaining a blood sample and performing fish necropsy for fish health assessments
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government