SHRIMP BLACK GILL DISEASE IS CLIMATE DRIVEN BUT THE CATASTROPHIC DECLINE OF THE GEORGIA COMMERCIAL FISHERY IS LIKELY A RESULT OF SOCIOECONOMIC FACTORS

The performance of the penaeid shrimp fishery in the US Southeast has declined significantly over the past several decades. Declines have been coincident with the emergence of shrimp Black Gill (sBG) disease caused by the parasitic apostome ciliate Hyalophysa lynni. A causal relationship between sBG disease and commercial shrimp stocks has not, however, been demonstrated. The goal of this study was to analyze long-term commercial shrimp landings, fishing effort, sBG disease prevalence, and environmental parameters to determine whether sBG disease is responsible for the decline in the performance of the Georgia shrimp fishery. A derived variable representing the annual emergence time (ε) of sBG disease was significantly correlated with climate indices, winter water temperatures and the performance of the fishery, suggesting that climate associated warming has resulted in the earlier emergence of sBG disease and that microbial parasites of crustaceans may be “climate winners”. However, commercial shrimp landings normalized for fishing effort remain flat over time, suggesting that the effect of earlier sBG disease emergence on the fishery has been minimal, and that socioeconomic factors that depress prices and increase fishing costs are likely the larger contributors to the decline in the fishery.

Presentation Preference: Either

Primary Presenter: Marc Frischer, Skidaway Institute of Oceanography (Univ of GA) (frischer@uga.edu)

Authors:

Marc Frischer, University of Georgia, Skidaway Institute of Oceanography  (frischer@uga.edu)

Max Braun, University of Georgia, Skidaway Institute of Oceanography  (frischer@uga.edu)

Megan Tomamichel, University of Georgia, Odum School of Ecology  (megan.tomamichel@uga.edu)

James Byers, University of Georgia, Odum School of Ecology  (jebbyers@gmail.com)