Electric Fish Handling Gloves Provide Effective Immobilization and Do Not Impede Reflex Recovery of Adult Largemouth Bass

Abstract

Electric fish handling gloves (FHGs) have been developed to immobilize fish during handling, with the potential benefit of reducing the time needed for sedation and recovery of fish relative to chemical anaesthetics. We examined the secondary stress responses (i.e., hematocrit, blood glucose, lactate, and pH) and reflex responses of Largemouth Bass Micropterus salmoides that were immobilized in water using electric FHGs for multiple durations (0, 30, and 120 s) relative to fish that were handled using only bare hands in water. We also evaluated the efficacy of the immobilization by quantifying the number of volitional movements that were observed during handling. Our findings suggested that when FHGs were used, fish tended to remain still (i.e., to show full reflex impairment) during handling relative to controls. Fish that were held with FHGs showed negligible reflex impairment immediately after the electricity was terminated. After a 30-min posttreatment retention period, blood chemistry and ventilation rates were similar between fish held with FHGs and those held with bare hands. This study supports the notion that electric FHGs are a safe and effective tool for practitioners who need to temporarily immobilize fish for handling, enumeration, or performing various scientific procedures.

Received November 15, 2016; accepted February 26, 2017 Published online May 4, 2017

ACKNOWLEDGMENTS

We thank the Ontario Universities Program in Field Biology and Queen’s University for hosting this research team. S.J.C. is supported by the Natural Sciences and Engineering Research Council of Canada (Discovery Grant, Strategic Grant, and the Ocean Tracking Network), the Canada Research Chairs program, and the Canada Foundation for Innovation.