Michigan's Adventures with Fisheries Management and VHSv: The Delicate Dance Between Science and Policy

A new virulent pathogen, Viral Hemorrhagic Septicemia virus (VHSv - Type IVb), was first identified in 2005 with an epizootic event in the Great Lakes with subsequent mortality events from 2006 to 2011.  This is a virus, which was not suppose to invade freshwater systems or affect coolwater fish species, but both assumptions were quickly shown to be incorrect.  This paper traces how a fisheries agency (MI DNR – Fisheries Division) responded to this challenge and details the process from chaos and confusion to enlightenment and active management against the pathogen.  A tool box was developed to understand and manage VHSv using targeted rapid response research focused on improved testing, surveillance, determining transmission vectors and susceptibility, broodstock restrictions, fish stocking changes, and angler regulations.  Given the lack of information on VHSv in freshwater systems in 2006, an extreme risk-negative approach was implemented that restricted management options and remained in place through 2010.  Rapid advancements in our knowledge on VHSv during the period 2008 to 2011 has allowed an active risk management program for fish management to be implemented based on the timely new research data concerning VHSv: susceptibility, detection locations, disease course, disinfection effectiveness, and vertical transmission.