Paul Hershberger, Ph.D.

Paul Hershberger is the Station Leader and a Research Fish Biologist at the U. S. Geological Survey - Marrowstone Marine Field Station.  He is an Affiliate Associate Professor at the School of Aquatic and Fishery Sciences – University of Washington, and former President of the Fish Health Section - American Fisheries Society.



Ph.D. 1998. Fisheries, School of Aquatic and Fisheries Sciences, University of Washington, Seattle, WA

M.S. 1995. Fisheries, School of Aquatic and Fisheries Sciences, University of Washington, Seattle, WA

B.S. 1993. Chemistry and Biology, Northland College, Ashland, WI


Research Interests:                                    

Paul's research is directed towards understanding, forecasting, and mitigating the impacts of infectious and parasitic diseases on populations of wild marine and anadromous fishes.  Current projects include:

1)  The Prince William Sound Herring Disease Program (Exxon Valdez Oil Spill Trustee Council)

Using an approach that involves a combination of field - and laboratory-based studies, we are investigating fish health factors that contribute to the failed recovery of Pacific herring populations in Prince William Sound.  A field-based component provides infection and disease prevalence data that informs the Prince William Sound fish forecasting model, serological data that indicates the prior exposure history and future susceptibility of herring to VHS, and diet information that will provide insights into Ichthyophonus demographic patterns in herring.  A laboratory component validates the newly-developed plaque neutralization assay as a quantifiable measure of herd immunity, identifies disease cofactors including temperature and salinity, investigates the possibility of an invertebrate host for Ichthyophonus, and assesses the virulence of other endemic pathogens to Pacific herring.


2)  Nanophyetus in Puget Sound Steelhead (USGS – Ecosystems, Washington Department of Fish and Wildlife, Long Live the Kings).

Steelhead smolts originating in some Puget Sound streams experience high mortality rates (approximately 80%) from their river mouths to the Pacific Ocean. The specific factors influencing mortality remain unknown, although it is clear from telemetry studies that mortality is rapid, occurs primarily in the marine environment, and some is caused by pinniped predation.  Nanopheytus salmonica infections may cause direct mortality or indirect mortality by compromising the physical condition of migration steelhead smolts, thereby predisposing them to a greater risk of predation.  Recent fish health assessments indicate high prevalence and intensity of Nanopheytus salmonica infections in steelhead out-migrants from Central and South Puget Sound Rivers where early marine survival is particularly low. This project is intended to assess and mitigate the impacts of Nanophyetus infections in these outmigrating smolts.



2003 to Present - Research Fish Biologist, U.S. Geological Survey, Western Fisheries Research Center, Marrowstone Marine Field Station, Nordland, WA

2010 to Present - Affiliate Associate Professor, School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA