Electrosedation of freshwater fishes for the surgical implantation of transmitters

Abstract

Although electrosedation is becoming a frequently used technique to anaesthetize fish for a variety of commercial, management, and research applications, limited information is available on the effectiveness of different settings (e.g., voltage, frequency, shocking duration) and target species. We examined recovery times and short-term survival while using a commercially available electroanaesthesia unit to prepare fishes for transmitter implantation surgeries and ran experimental tests without surgery on different electrosedation settings. Our results indicate that electrosedation is a quick and efficient form of anaesthesia, with full anaesthesia achieved, surgeries completed, and recovery in under 10 min for common carp (Cyprinus carpio L., 1758), goldfish (Carassius auratus (L. 1758)), and others. We had zero mortality over at least 24 h associated with electrosedation. We found no significant differences in recovery times related to species or mass, nor did we find any significant changes to recovery time when changing voltage applied, frequency, shocking duration, or when changing the type of pulse applied (e.g., burst pulses vs. standard pulse). Although further researches are needed to address the sublethal and long-term effects of eletrosedation, these findings are important to researchers for selecting suitable target species and optimizing recovery time and survival for a quick release after surgery, tagging, or any time fish sedation is required.

Comparing Immobilization, Recovery, and Stress Indicators Associated with Electric Fish Handling Gloves and a Portable Electrosedation System

“…Strokes were administered every 15 s for 3 min (Kim et al. ), during which time opercular beats were quantified. Fish were then transferred to a cooler filled with lake water and independent aeration.…”

“…Simulation of surgery was administered anterior to the pelvic girdle by using stroking motions with the blunt end of a scalpel handle. Strokes were administered every 15 s for 3 min (Kim et al 2017), during which time opercular beats were quantified. Fish were then transferred to a cooler filled with lake water and independent aeration.…”

Individual variation influences avoidance behaviour of invasive common carp (

“…Fishes were held at the Aquatic Life Research Facility (Burlington, ON, Canada) before release. For acoustic tagging, individuals were anaesthetised with a Portable Electrosedation System (PES, Smith-Root Inc., Vancouver, BC, Canada; Kim et al 2017) and then weighed, measured and implanted with a 19 mm HTI TM acoustic tag (Model 900 LV, Hydroacoustic Technology Inc., Seattle, WA, USA) via surgical incision. After a monitored recovery, individuals were transferred to holding tanks for 24 h before they were transferred to the mesocosm.…”

Identification of predation events in wild fish using novel acoustic transmitters

“…Fish were captured within the study site using a boat electrofisher, held for a maximum of 15 min in a cooler with ambient river water, and transferred to a larger research vessel for surgical tag implantation. The first six fish tagged were anaesthetized in a buffered solution of tricaine methanesulfonate (MS-222; 100 mg/L) and the rest were electrosedated using a PES unit to decrease fish handling and recovery times overall ( [12,13]; 4 s pulsed DC, 100 V, 30 Hz, and 25% duty cycle; Smith-Root Inc, Washington). We examined data for fish tagged using both methods and did not find any discernable patterns in predation or habitat use, as such these methods were not considered as factors in analyses.…”