Paul Hershberger is the Chief of the Fish Heath Section at the U. S. Geological Survey - Western Fisheries Research Center (Seattle, WA) and the Station Leader at the Marrowstone Marine Field Station (Nordland, WA). He is an Affiliate Professor at the University of Washington – School of Aquatic and Fishery Sciences, and former President of the Fish Health Section - American Fisheries Society.
Paul has the pleasure of leading a team of fish health professionals who are experts in their respective fields of fish virology, immunology, toxicology, histopathology, parasitology, and disease ecology. Specific components of the Fish Health Section focus on:
- the development of immune-related tools for fishes and the impact(s) of environmental stressors (e.g. contaminants, pathogens, temperature) on the fish immune response.
- the use of gene knock outs in zebrafish and other model species to assess pathogen virulence and host immune response mechanisms.
- the evolution of virulence and other phenotypes in fish viruses using landscape-scale genotyping to identify patterns of virus occurrence, transmission, and disease impacts across borad temporal and geographic scales.
- the discovery and identification of new and emerging fish viruses in the Pacific Northwest and throughout North America.
- the integration of novel quantitative techniques to understand stochasticity of pathogen transmission and other mechanisms of basic and applied disease ecology.
- the use of histopathology and electron microscopy to assess pathogen / disease monitoring and research needs in populations of wild and hatchery-raised fishes.
- the effects of environmental contaminants, including PAH’s, PCB’s, and emerging contaminants like PFAS and 6-PPD quinone on fish health, survival, and immunological pathways.
- the range expansion of invasive amphibians and their susceptibility to native and exotic pathogens.
In addition, Paul’s personal research employs a combination of laboratory and field approaches to understand, forecast, and mitigate the impacts of infectious and parasitic diseases on populations of wild marine and anadromous fishes.
Professional Experience
2022 to Present: Fish Health Section Chief, U.S. Geological Survey, Western Fisheries Research Center, Seattle, WA
2003 to Present – Station Leader, U.S. Geological Survey, Western Fisheries Research Center, Marrowstone Marine Field Station, Nordland, WA
2004 to Present – Member of the Affiliate Faculty, School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA
Education and Certifications
Ph.D. Fisheries, School of Aquatic and Fisheries Sciences, University of Washington, Seattle, WA
M.S. Fisheries, School of Aquatic and Fisheries Sciences, University of Washington, Seattle, WA
B.S. Chemistry and Biology, Northland College, Ashland, WI
Science and Products
Evaluating the effect of nuclear inclusion X (NIX) infections on Pacific razor clam populations
A phylogeny based on cytochrome-c oxidase gene sequences identifies sympatric Ichthyophonus genotypes in the NE Pacific Ocean
A novel approach for directly incorporating disease into fish stock assessment: A case study with seroprevalence data
Annual recurrences of viral hemorrhagic septicemia epizootics in age 0 Pacific herring Clupea pallasii Valenciennes, 1847
Herring Disease Program - Annual Project Report 2012011-E, February 1, 2010-January 31, 2021
Long-term shedding from fully convalesced individuals indicates that Pacific herring are a reservoir for viral hemorrhagic septicemia virus
Differential susceptibility of Yukon River and Salish Sea stocks of Chinook salmon Oncorhynchus tshawytscha to ichthyophoniasis
Novel diagnostic tests for the putative agent of bacterial gill disease in Pacific razor clams (Siliqua patula)
Anadromous coastal cutthroat trout Oncorhynchus clarkii clarkii as a host for Argulus pugettensis (Crustacea, Branchiura): Parasite prevalence, intensity and distribution
Pacific herring Clupea pallasii are not susceptible to vibriosis from Vibrio anguillarum or V. ordalii under laboratory conditions
Herring Disease Program II 19120111-E - 2019 Annual Report
Climate change can drive marine diseases
Partners - FHP
Fish Health Program Lead Scientists and Areas of Expertise
Species Studied by the Fish Health Program
Tribal Collaboration - Fish Health Program (FHP)
Phylogenetics of Ichthyophonus parasites
PCB Exposure and Disease Susceptibility
PAH Exposure and Disease Susceptibility
Species Studied at the Marrowstone Marine Field Station
Effects of Nanophyetus salmincola on the Health and Survival of Puget Sound Steelhead
Genomic Mechanisms that Underlie Lack of Recovery of Prince William Sound Herring Following the 1990s Collapse
Herring Disease Program
Nanophyetus salmincola - MMFS
Histological and molecular testing of nuclear inclusion X in Pacific Razor clams from select locations in Washington, USA
Survey of viral hemorrhagic septicemia virus in Pacific herring throughout the North Pacific Ocean
Laboratory challenge of Pacific herring Clupea pallasii to Vibrio anguillarum and V. ordallii
Science and Products
- Publications
Filter Total Items: 112
Evaluating the effect of nuclear inclusion X (NIX) infections on Pacific razor clam populations
ABSTRACT: Nuclear inclusion X (NIX), the etiological agent of bacterial gill disease in Pacific razor clams Siliqua patula, was associated with host mortality events in coastal Washington State, USA, during the mid-1980s. Ongoing observations of truncated razor clam size distributions in Kalaloch Beach, Washington, raised concerns that NIX continues to impact populations. We conducted a series ofA phylogeny based on cytochrome-c oxidase gene sequences identifies sympatric Ichthyophonus genotypes in the NE Pacific Ocean
ABSTRACT: In recent decades, evidence has accumulated to suggest that the widespread and highly variable parasite Ichthyophonus hoferi is actually a species complex. Highly plastic morphology and a general lack of defining structures has contributed to the likely underestimate of biodiversity within this group. Molecular methods are a logical next step in the description of these parasites, but maA novel approach for directly incorporating disease into fish stock assessment: A case study with seroprevalence data
When estimating mortality from disease with fish population models, common disease surveillance data such as infection prevalence are not always informative, especially for fast-acting diseases that may go unobserved in infrequently sampled populations. In these cases, seroprevalence — the proportion of fish with measurable antibody levels in their blood — may be more informative. In cases of lifeAnnual recurrences of viral hemorrhagic septicemia epizootics in age 0 Pacific herring Clupea pallasii Valenciennes, 1847
Throughout a 20 year biosurveillance period, viral hemorrhagic septicemia virus was isolated in low titers from only 6/7355 opportunistically sampled adult Pacific herring, reflecting the typical endemic phase of the disease when the virus persists covertly. However, more focused surveillance efforts identified the presence of disease hot spots occurring among juvenile life history stages from cerHerring Disease Program - Annual Project Report 2012011-E, February 1, 2010-January 31, 2021
We will investigate fish health factors that may be contributing to the failed recovery of Pacific herring populations in Prince William Sound. Field samples will provide infection and disease prevalence data from Prince William Sound and Sitka Sound to inform the age structured assessment (ASA) model, serological data will indicate the prior exposure history and future susceptibility of herring tLong-term shedding from fully convalesced individuals indicates that Pacific herring are a reservoir for viral hemorrhagic septicemia virus
Processes that allow viral hemorrhagic septicemia (VHS) virus to persist in the marine environment remain enigmatic, owing largely to the presence of covert and cryptic infections in marine fishes during typical sub-epizootic periods. As such, marine host reservoirs for VHS virus have not been fully demonstrated, nor have the mechanism(s) by which infected hosts contribute to virus perpetuation anDifferential susceptibility of Yukon River and Salish Sea stocks of Chinook salmon Oncorhynchus tshawytscha to ichthyophoniasis
Preliminary evidence suggests that Chinook salmon Oncorhynchus tshawytscha from the Yukon River may be more susceptible to Ichthyophonus sp. infections than Chinook from stocks further south. To investigate this hypothesis in a controlled environment, we experimentally challenged juvenile Chinook from the Yukon River and from the Salish Sea with Ichthyophonus sp. and evaluated mortality, infectionNovel diagnostic tests for the putative agent of bacterial gill disease in Pacific razor clams (Siliqua patula)
Nuclear inclusion X (NIX) is a gamma proteobacteria that infects the nuclei of gill epithelial cells in Pacific razor clams. NIX has been associated with clam die-offs in coastal Washington. A quantitative PCR (qPCR) assay was developed to detect NIX in Pacific razor clams, and assay specificity was confirmed by chromogenic in situ hybridization (CISH). Both tests were applied to evaluate NIX infeAnadromous coastal cutthroat trout Oncorhynchus clarkii clarkii as a host for Argulus pugettensis (Crustacea, Branchiura): Parasite prevalence, intensity and distribution
Coastal cutthroat trout [Oncorhynchus clarkii clarkii (Richardson, 1836)] from the marine waters of Puget Sound, WA, was documented as a new host for the ectoparasite Argulus pugettensis (Dana, 1852). The prevalence of A. pugettensis was 66% (49 of 74) on cutthroat trout and 0% (0 of 55) on coho salmon [O. kisutch (Walbaum, 1792)] collected during the winter of 2017/2018. Infestations occurred mosPacific herring Clupea pallasii are not susceptible to vibriosis from Vibrio anguillarum or V. ordalii under laboratory conditions
The ubiquity of Vibrio spp. throughout the coastal marine waters of the Pacific Northwest of North America raises questions about the susceptibility of native marine fishes, including Pacific herring (Clupea pallasii). Early reports of Vibriolike disease (Rucker et al., 1954; Walford, 1958) and Vibrio sp. isolations (Pacha & Kiehn, 1969) in Pacific herring remain questionable because both occurredHerring Disease Program II 19120111-E - 2019 Annual Report
We will investigate fish health factors that may be contributing to the failed recovery of Pacific herring populations in Prince William Sound. Field samples will provide infection and disease prevalence data from Prince William Sound and Sitka Sound that will inform the ASA model, serological data that will indicate the prior exposure history and future susceptibility of herring to VHS, and dietClimate change can drive marine diseases
As an ultimate driver of marine ecosystem processes, climate change is expected to influence proximate disease drivers in marine systems. The observable effects of climate change, including changes in temperature, hypoxia, CO2 accumulation, precipitation, and storm and cyclone frequencies and intensities, may directly act as proximate drivers of marine disease, especially in poikilotherms. These c - Science
Filter Total Items: 28
Partners - FHP
For more than five decades the WFRC Fish Health Program has worked with partners to provide research findings to managers of aquatic resources. Those partners form a network of colleagues, co-investigators, and customers. Our partners include Department of the Interior bureaus, tribal and state fisheries agencies, other federal partners and the private sector.Fish Health Program Lead Scientists and Areas of Expertise
Lead Scientists - ExpertiseSpecies Studied by the Fish Health Program
List of species studied by the Fish Health Program. These species include bacteria, fish, parasites, and viruses. The list contains both common and scientific names. Descriptions of species and studies can be found under the "Related Science" tab.Tribal Collaboration - Fish Health Program (FHP)
The Fish Health Program has a strong commitment to respond to requests for research and technical support from Tribal fisheries agencies.Phylogenetics of Ichthyophonus parasites
Ichthyophonus spp. are perhaps the most economically and ecologically important parasites of wild marine fish in the world.PCB Exposure and Disease Susceptibility
Researchers at that MMFS are experimentally determining the impacts of high PCB body burdens on the immunocompetency and disease susceptibility of Pacific herring.PAH Exposure and Disease Susceptibility
Researchers at the MMFS are studying the immediate and delayed effects of petroleum hydrocarbon exposures to Pacific herring.Species Studied at the Marrowstone Marine Field Station
The Disease Ecology Research Program at the Marrowstone Marine Field Station addresses fundamental disease processes that impact wild marine and anadromous fishes. The program is not designed around particular host or pathogen species; rather we investigate diseases processes that involve numerous species of marine hosts and pathogens. Please follow the links for more information about some of the...Effects of Nanophyetus salmincola on the Health and Survival of Puget Sound Steelhead
Low early marine survival rates of Puget Sound steelhead (Oncorhynchus mykiss), the state fish of Washington, have contributed to its dramatic population decline and current listing as a “Threatened Species” under the Endangered Species Act. Determining the cause(s) of this elevated mortality remains a primary objective of the Salish Sea Marine Survival Project, a large US / Canada effort...Genomic Mechanisms that Underlie Lack of Recovery of Prince William Sound Herring Following the 1990s Collapse
In the decades following the Exxon Valdez Oil Spill (EVOS), it has become increasingly apparent that oil can be toxic at extremely low concentrations to developing fish embryos including herring, where some toxic phenotypes may be apparent during embryogenesis, but some are delayed until later in life. Therefore, acute and lingering oil may act as an insidious selective force within populations...Herring Disease Program
Using an approach that involves a combination of field- and laboratory-based studies, we are investigating fish health factors that may be contributing to the failed recovery of Pacific herring populations in Prince William Sound, AK. Field studies are providing infection and disease prevalence data to inform the population models, serological data that indicate the prior exposure history and...Nanophyetus salmincola - MMFS
Fish Parasite - Nanophyetus salmincola - Data
Histological and molecular testing of nuclear inclusion X in Pacific Razor clams from select locations in Washington, USA
Nuclear inclusion X (NIX), the etiological agent of bacterial gill disease in Pacific razor clams (Siliqua patula) was associated with host mortality events in coastal Washington, USA during the mid-1980s. Ongoing observations of truncated razor clam size distributions in Kalaloch Beach, Washington raised concerns that NIX continues to impact populations. We conducted a series of spatial and longiSurvey of viral hemorrhagic septicemia virus in Pacific herring throughout the North Pacific Ocean
Throughout a 20-year biosurveillance period, viral hemorrhagic septicemia virus was isolated in low titers from only 6 / 7,355 opportunistically sampled adult Pacific herring, reflecting the typical endemic phase of the disease when the virus persists covertly. However, more focused surveillance efforts identified the presence of disease hot spots occurring among juvenile life history stages fromLaboratory challenge of Pacific herring Clupea pallasii to Vibrio anguillarum and V. ordallii
Controlled waterborne exposures of Pacific herring (Clupea pallasii) to Vibrio anguillarum and V. ordalii failed to result in overt signs of disease or mortality from vibriosis. Cumulative mortalities among Vibrio - exposed Pacific herring (3.3 - 5.0 percent) were similar to those of saline-exposed negative controls (10 percent) and significantly less (P less than 0.001) than those of Vibrio - exp - Multimedia
- News