Assessing the potential for using low-frequency electric deterrent barriers to reduce lake sturgeon (Acipenser fulvescens) entrainment

Given the limited evidence on utilizing low-frequency electrical fields as deterrents to fish, we studied lake sturgeon (Acipenser fulvescens Rafinesque, 1817) behavioural responses and short-term physiological reactions to low-frequency (0.1-50 Hz) low-voltage (0.024-0.3 v) electric fields. Fish from 2 year classes were used as a means of including size considerations in the study. Individuals from both year classes exhibited differing responses to the same electric fields, with smaller, younger fish being more reactive to the electric stimulation of the fields than /older, larger fish. The smaller, younger fish also had reduced weight gain 30 days post experiment compared with fish that were a year older. Short-term physiological effects were observed in the older, larger fish in the form of elevated blood glucose levels. Our results show that individuals can acclimatize to electric fields in a relatively short time period and that larger individuals tend to be less affected by low-frequency/low-voltage electric fields than smaller fish. Testing the utility of electric deterrents in a more realistic riverine setting using pulsating electric field is, therefore, highly recommended to ensure decisions regarding the implementation of low-frequency/low-voltage electric barrier systems to reduce entrainment adequately account for possible sublethal effects on lake sturgeon.