Ichthyophonus in sport-caught groundfishes from southcentral Alaska

Bradley P. Harris; Sarah R. Webster; Nathan Wolf; Jacob L. Gregg; Paul Hershberger

doi:10.3354/dao03218

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Ichthyophonus in sport-caught groundfishes from southcentral Alaska

Bradley P. Harris·Sarah R. Webster·Nathan Wolf·Jacob L. Gregg·Paul Hershberger

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Abstract

This report of Ichthyophonus in common sport-caught fishes throughout the marine waters of southcentral Alaska represents the first documentation of natural Ichthyophonus infections in lingcod Ophiodon elongates and yelloweye rockfish Sebastes ruberrimus . In addition, the known geographic range of Ichthyophonus in black rockfish S. melanops has been expanded northward to include southcentral Alaska. Among all species surveyed, the infection prevalence was highest (35%, n = 334) in Pacific halibut Hippoglossus stenolepis . There were no gross indications of high-level infections or clinically diseased individuals. These results support the hypothesis that under typical conditions Ichthyophonus can occur at high infection prevalence accompanied with low-level infection among a variety of fishes throughout the eastern North Pacific Ocean, including southcentral Alaska.

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Diseases of Aquatic Organisms Article

Source-reported bounding extent: 59° to 61.5° latitude; -152° to -145° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Bradley P. Harris, Sarah R. Webster, Nathan Wolf, Jacob L. Gregg, Paul Hershberger. 2018. Ichthyophonus in sport-caught groundfishes from southcentral Alaska. https://doi.org/10.3354/dao03218

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