Use of electronarcosis to immobilize juvenile lake and shortnose sturgeons for handling and the effects on their behavior

Low voltage constant direct current was used to immobilize juvenile lake (Acipenser fulvescens) and shortnose sturgeons (A. brevirostrum). There was no significant difference in time/ the lake or shortnose sturgeons required to exhibit positive rheotaxis between fish immobilized with electricity and control fish (two-way ANOVA, P = 0.11). Fish immobilized with 80 mg L-1 tricaine took a significantly longer time to orient than control fish or fish immobilized with electricity for 5 or 30 min (one-way ANOVA, P = 0.003). Electronarcosis, which produces effects like a chemical anesthetic, is a useful technique for immobilizing juvenile sturgeons for handling. Fish can swim upright as soon as the electricity is turned off, recovery time is shorter than with chemical anesthetics, and the cost of equipment is < 400 USD.