title: Fishing diseased abalone to promote yield and conservation.
abstract: Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease-fishing models, we modelled targeting (culling) infected individuals, which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to the catch value. The non-selective abalone fishing required to eradicate parasites exceeded thresholds for abalone sustainability, but targeting infected abalone allowed the fishery to generate yield and reduce parasite prevalence while maintaining stock densities at or above the densities attainable if the population was closed to fishing. The effect was strong enough that stock and yield increased even when the catch was one-third uninfected abalone. These results could apply to other fisheries as the diagnostic costs decline relative to catch value.
authors.affiliation: College of the Environment and Life Sciences, University of Rhode Island, Kingston, RI 02881, USA Haskin Shellfish Research Laboratory, Rutgers University, Port Norris, NJ 08349, USA tal@hsrl.rutgers.edu.
authors.forename: Tal
authors.initials: T
authors.lastname: Ben-Horin
authors.affiliation: US Geological Survey, Western Ecological Research Center, c/o Marine Science Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
authors.forename: Kevin D
authors.identifier: http://orcid.org/0000-0001-7583-4593
authors.initials: KD
authors.lastname: Lafferty
authors.affiliation: Gulf Coast Research Laboratory, University of Southern Mississippi, Ocean Springs, MS 39564, USA.
authors.forename: Gorka
authors.initials: G
authors.lastname: Bidegain
authors.affiliation: Bren School of Environmental Science and Management, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
authors.forename: Hunter S
authors.initials: HS
authors.lastname: Lenihan
mesh_terms: D000818:Animals; D002140:California; D003247:Conservation of Natural Resources; D005398:Fisheries; D054884:Host-Pathogen Interactions; D008954:Models, Biological; D008974:Mollusca / Q000382:microbiology*; D011156:Population Density
keywords: abalone; fisheries management; host–parasite models; presumptive diagnosis; withering syndrome