An expert-based risk ranking framework for assessing pathogens in the
live baitfish trade
Abstract
As global trade of live animals expands, there is increasing need to
assess the risks of invasive organisms, including pathogens, that can
accompany these translocations. The movement and release of live
baitfish by recreational anglers has been identified as a particularly
high-risk pathway for the spread of aquatic diseases in the United
States. To provide risk-based decision support for preventing and
managing disease invasions from baitfish release, we developed a hazard
identification and ranking tool to identify the pathogens that pose the
highest risk to wild fish via this pathway. We created a screening
protocol and semi-quantitative stochastic risk ranking framework,
combining published data with expert elicitation (n=25) and applied the
framework to identify high-priority pathogens for the bait supply in
Minnesota, USA. Normalized scores were developed for seven risk criteria
(likelihood of transfer, prevalence in bait supply, likelihood of
colonization, current distribution, economic impact if established,
ecological impact if established, and host species) to characterize a
pathogen’s ability to persist in the bait supply and cause impacts to
wild fish species of concern. The generalist macroparasite
Schizocotyle acheilognathi was identified as presenting highest
overall threat, followed by the microsporidian Ovipleistophora
ovariae, and viral hemorrhagic septicemia virus. Our findings provide
risk-based decision support for managers charged with maintaining both
the recreational fishing industry and sustainable, healthy natural
resources. The ranking process, implemented here for a single state case
study, provides a standardized conceptual framework that could be
applied across jurisdictions to inform risk-based management of the live
baitfish pathway.