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.
Professional Experience
2022-Present: Research Fish Biologist, USGS EESC, Kearneysville, WV
2019-2022: Post-Doc Researcher, USGS EESC, Kearneysville, WV
2006-2019: Biological Science Technician/Contractor USGS EESC, Kearneysville, WV
Education and Certifications
Ph.D., Forest Resource Science Program, Wildlife and Fisheries Management Major, West Virginia University, 2018
M.S., Wildlife and Fisheries Management, West Virginia University, Morgantown, WV, 2011
B.S., Environmental Studies with a Concentration in Aquatic Science, Shepherd University, Shepherdstown, WV, 2008
B.S., Environmental Studies with a Concentration in Aquatic Science, Shepherd University, Shepherdstown, WV, 2008
Affiliations and Memberships*
American Fisheries Society, Fish Health Section
Northeast Fish Health Committee
Science and Products
Filter Total Items: 33
Tumours in white suckers from Lake Michigan tributaries: Pathology and prevalence
The prevalence and histopathology of neoplastic lesions were assessed in white suckerCatostomus commersonii captured at two Lake Michigan Areas of Concern (AOCs), the Sheboygan River and Milwaukee Estuary. Findings were compared to those observed at two non-AOC sites, the Root and Kewaunee rivers. At each site, approximately 200 adult suckers were collected during their spawning migration. Raised
Authors
Vicki S. Blazer, H.L. Walsh, R.P. Braham, C. M. Hahn, P. Mazik, P.B. McIntyre
Evidence of estrogenic endocrine disruption in smallmouth and largemouth bass inhabiting Northeast U.S. National Wildlife Refuge waters: A reconnaissance study
Intersex as the manifestation of testicular oocytes (TO) in male gonochoristic fishes has been used as an indicator of estrogenic exposure. Here we evaluated largemouth bass (Micropterus salmoides) or smallmouth bass (Micropterus dolomieu) form 19 National Wildlife Refuges (NWRs) in the Northeast U.S. inhabiting waters on or near NWR lands for evidence of estrogenic endocrine disruption. Waterbodi
Authors
Luke R. Iwanowicz, Vicki S. Blazer, A.E. Pinkney, C.P. Guy, A.M. Major, K. Munney, S. Mierzykowski, S. Lingenfelser, A. Secord, K. Patnode, T.J. Kubiak, C. Stern, Cassidy M. Hahn, Deborah D. Iwanowicz, Heather L. Walsh, Adam J. Sperry
Reproductive health indicators of fishes from Pennsylvania watersheds: association with chemicals of emerging concern
Fishes were collected at 16 sites within the three major river drainages (Delaware, Susquehanna, and Ohio) of Pennsylvania. Three species were evaluated for biomarkers of estrogenic/antiandrogenic exposure, including plasma vitellogenin and testicular oocytes in male fishes. Smallmouth bass Micropterus dolomieu, white sucker Catostomus commersonii, and redhorse sucker Moxostoma species were collec
Authors
V. S. Blazer, D.D. Iwanowicz, H.L. Walsh, A.J. Sperry, L. R. Iwanowicz, D.A. Alvarez, R.A. Brightbill, G. Smith, W.T. Foreman, R. Manning
Assessment of the fish tumor beneficial use impairment in brown bullhead (Ameiurus nebulosus) at selected Great Lakes Areas of Concern
A total of 878 adult Brown Bullhead were collected at 11 sites within the Lake Erie and Lake Ontario drainages from 2011 to 2013. The sites included seven Areas of Concern (AOC; 670 individuals), one delisted AOC (50 individuals) and three non-AOC sites (158 individuals) used as reference sites. These fish were used to assess the “fish tumor or other deformities” beneficial use impairment. Fish we
Authors
Vicki Blazer, Patricia M. Mazik, Luke R. Iwanowicz, Ryan P. Braham, Cassidy M. Hahn, Heather L. Walsh, Adam J. Sperry
Monitoring of wild fish health at selected sites in the Great Lakes Basin: methods and preliminary results
During fall 2010 and spring 2011, a total of 119 brown bullhead (Ameiurus nebulosus), 136 white sucker (Catostomus commersoni), 73 smallmouth bass (Micropterus dolomieu), and 59 largemouth bass (M. salmoides) were collected from seven Great Lakes Basin Areas of Concern and one Reference Site. Comprehensive fish health assessments were conducted in order to document potential adverse affects from e
Authors
Vicki Blazer, Patricia M. Mazik, Luke R. Iwanowicz, Ryan Braham, Cassidy Hahn, Heather L. Walsh, Adam Sperry
Health of white sucker within the St. Louis River area of concern associated with habitat usage as assessed using stable isotopes
In Spring 2011, 200 adult white sucker were collected in four areas of the St. Louis River area of concern (AOC), located in Minnesota and Wisconsin, USA. The areas included the upper AOC as a reference area, the upper estuary, St. Louis Bay and Superior Bay. Grossly visible abnormalities were documented and preserved for microscopic analyses, as were five to eight representative pieces of liver t
Authors
V. S. Blazer, J. Hoffman, H.L. Walsh, R.P. Braham, C. Hahn, P. Collins, Z. Jorgenson, T. Ledder
The effects of disease-related mortality on the recruitment of young-of-year smallmouth bass in the Susquehanna River Basin, Pennsylvania
No abstract available.
Authors
Geoffrey Smith, Vicki Blazer, Heather Walsh, Luke R. Iwanowicz, Clifford E. Starliper, Adam Sperry
Bacterial etiology in diseased fishes, primarily smallmouth bass Micropterus dolomieu, within the Chesapeake Bay drainage in 2009-2011
No abstract available.
Authors
Clifford E. Starliper, Vicki Blazer, Luke R. Iwanowicz, Heather L. Walsh
Description of two new gill myxozoans from smallmouth (Micropterus dolomieu) and largemouth bass (Micropterus salmoides)
Two previously undescribed species of myxozoan parasites were observed in the gills of bass inhabiting the Potomac and James River basins. They are described using morphological characteristics and small-subunit (SSU) rDNA gene sequences. Both were taxonomically identified as new species of Myxobolus; Myxobolus branchiarum n. sp. was found exclusively in smallmouth bass, and Myxobolus micropterii
Authors
Heather L. Walsh, Luke R. Iwanowicz, Gavin W. Glenney, Deborah D. Iwanowicz, Vicki Blazer
Science and Products
- Science
- Data
No Result Found
- Multimedia
No results found.
- Publications
Filter Total Items: 33
Tumours in white suckers from Lake Michigan tributaries: Pathology and prevalence
The prevalence and histopathology of neoplastic lesions were assessed in white suckerCatostomus commersonii captured at two Lake Michigan Areas of Concern (AOCs), the Sheboygan River and Milwaukee Estuary. Findings were compared to those observed at two non-AOC sites, the Root and Kewaunee rivers. At each site, approximately 200 adult suckers were collected during their spawning migration. RaisedAuthorsVicki S. Blazer, H.L. Walsh, R.P. Braham, C. M. Hahn, P. Mazik, P.B. McIntyreEvidence of estrogenic endocrine disruption in smallmouth and largemouth bass inhabiting Northeast U.S. National Wildlife Refuge waters: A reconnaissance study
Intersex as the manifestation of testicular oocytes (TO) in male gonochoristic fishes has been used as an indicator of estrogenic exposure. Here we evaluated largemouth bass (Micropterus salmoides) or smallmouth bass (Micropterus dolomieu) form 19 National Wildlife Refuges (NWRs) in the Northeast U.S. inhabiting waters on or near NWR lands for evidence of estrogenic endocrine disruption. WaterbodiAuthorsLuke R. Iwanowicz, Vicki S. Blazer, A.E. Pinkney, C.P. Guy, A.M. Major, K. Munney, S. Mierzykowski, S. Lingenfelser, A. Secord, K. Patnode, T.J. Kubiak, C. Stern, Cassidy M. Hahn, Deborah D. Iwanowicz, Heather L. Walsh, Adam J. SperryReproductive health indicators of fishes from Pennsylvania watersheds: association with chemicals of emerging concern
Fishes were collected at 16 sites within the three major river drainages (Delaware, Susquehanna, and Ohio) of Pennsylvania. Three species were evaluated for biomarkers of estrogenic/antiandrogenic exposure, including plasma vitellogenin and testicular oocytes in male fishes. Smallmouth bass Micropterus dolomieu, white sucker Catostomus commersonii, and redhorse sucker Moxostoma species were collecAuthorsV. S. Blazer, D.D. Iwanowicz, H.L. Walsh, A.J. Sperry, L. R. Iwanowicz, D.A. Alvarez, R.A. Brightbill, G. Smith, W.T. Foreman, R. ManningAssessment of the fish tumor beneficial use impairment in brown bullhead (Ameiurus nebulosus) at selected Great Lakes Areas of Concern
A total of 878 adult Brown Bullhead were collected at 11 sites within the Lake Erie and Lake Ontario drainages from 2011 to 2013. The sites included seven Areas of Concern (AOC; 670 individuals), one delisted AOC (50 individuals) and three non-AOC sites (158 individuals) used as reference sites. These fish were used to assess the “fish tumor or other deformities” beneficial use impairment. Fish weAuthorsVicki Blazer, Patricia M. Mazik, Luke R. Iwanowicz, Ryan P. Braham, Cassidy M. Hahn, Heather L. Walsh, Adam J. SperryMonitoring of wild fish health at selected sites in the Great Lakes Basin: methods and preliminary results
During fall 2010 and spring 2011, a total of 119 brown bullhead (Ameiurus nebulosus), 136 white sucker (Catostomus commersoni), 73 smallmouth bass (Micropterus dolomieu), and 59 largemouth bass (M. salmoides) were collected from seven Great Lakes Basin Areas of Concern and one Reference Site. Comprehensive fish health assessments were conducted in order to document potential adverse affects from eAuthorsVicki Blazer, Patricia M. Mazik, Luke R. Iwanowicz, Ryan Braham, Cassidy Hahn, Heather L. Walsh, Adam SperryHealth of white sucker within the St. Louis River area of concern associated with habitat usage as assessed using stable isotopes
In Spring 2011, 200 adult white sucker were collected in four areas of the St. Louis River area of concern (AOC), located in Minnesota and Wisconsin, USA. The areas included the upper AOC as a reference area, the upper estuary, St. Louis Bay and Superior Bay. Grossly visible abnormalities were documented and preserved for microscopic analyses, as were five to eight representative pieces of liver tAuthorsV. S. Blazer, J. Hoffman, H.L. Walsh, R.P. Braham, C. Hahn, P. Collins, Z. Jorgenson, T. LedderThe effects of disease-related mortality on the recruitment of young-of-year smallmouth bass in the Susquehanna River Basin, Pennsylvania
No abstract available.AuthorsGeoffrey Smith, Vicki Blazer, Heather Walsh, Luke R. Iwanowicz, Clifford E. Starliper, Adam SperryBacterial etiology in diseased fishes, primarily smallmouth bass Micropterus dolomieu, within the Chesapeake Bay drainage in 2009-2011
No abstract available.AuthorsClifford E. Starliper, Vicki Blazer, Luke R. Iwanowicz, Heather L. WalshDescription of two new gill myxozoans from smallmouth (Micropterus dolomieu) and largemouth bass (Micropterus salmoides)
Two previously undescribed species of myxozoan parasites were observed in the gills of bass inhabiting the Potomac and James River basins. They are described using morphological characteristics and small-subunit (SSU) rDNA gene sequences. Both were taxonomically identified as new species of Myxobolus; Myxobolus branchiarum n. sp. was found exclusively in smallmouth bass, and Myxobolus micropteriiAuthorsHeather L. Walsh, Luke R. Iwanowicz, Gavin W. Glenney, Deborah D. Iwanowicz, Vicki Blazer
*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