Barge Electrofishing | U.S. Fish & Wildlife Service

Barge Electrofishing

Description

Barge Electrofishing Example

Electrofishing is the application of electricity into water to capture or control fish. Electrofishing gear takes several forms, the most common types are backpack, barge, and boat electrofishers. Barge electrofishing is portable and is typically used in mid-sized wadeable streams. All three major waveform types (Alternating Current [AC], Direct Current [DC], and Pulsed Direct Current [PDC] including Gated Burst variations can be used. For the purposes of this discussion, DC or PDC output is assumed. Accordingly, electrode terminology will refer to anodes and cathodes.

Type	Active
Habitat deployed	Mid-sized, shallow (wadeable) streams. Also, along shallow shorelines of ponds, lakes, and backwaters.
Target species	Small to mid-sized individuals of a diverse array of warmwater and coldwater species. Barge electrofishing often captures larger individuals than backpack electrofishing.

Overview

Barge electrofishers or “shockers” are portable and have power capacities approaching that of boat electrofishers. Commonly, crews carry barges over a distance or rough terrain to launch, and must maneuver through shallow water habitats, thus smaller-sized generators are necessary (2,500 average Watts). Occasionally, when stream access is relatively easy and maneuverability through shallow water zones is not a concern, larger generators can be used, up to 6,500+ average Watts The barge operator preferably pushes the barge from the stern so that the control box and safety switches can be continuously managed. A minimum crew size of three is indicated if using a stern operator position. Barges can employ 1 - 4 hand-held electrodes (anodes if outputting direct current). Thus, crew size varies from (2)3-4 members to 10 or more. Primary roles are barge operator, electrode handler, dip netter, and bucket carrier for captured fishes. It is good if one person can act as a supervisor, especially when >1 hand-held electrode is deployed and with larger crew sizes. The hand-held electrode operator also may use a dipnet as well as the bucket carrier.

Barge crew with two hand-held electrodes

Barge crew with two hand-held electrodes (anodes in this case as the output is pulsed DC). Operator is pushing the barge and is depressing a safety switch on the white push bar.

Barge crew with two hand-held electrodes B

Barge crew with two hand-held electrodes (anodes in this case as the output is pulsed DC). Operator is pushing the barge and is depressing a safety switch on the white push bar.

Closeup of anode crews.

Closeup of anode crews. Note the earplugs worn by the dip netters

Rearview of the two-anode barge crew operation.

Rearview of the two-anode barge crew operation. Note the floats on the anode cables.

Operator is transferring his catch

Anode operator is transferring his catch to the dip netter and exchanging nets.

The dip netter is transferring captured fish to the live well.

The dip netter is transferring captured fish to the live well. Note the deeper water habitat being sampled in this picture.

Pros

Portable (but less so than backpack gear)
Higher power capacity, intermediate between backpack and boat electrofishers; thus, can sample more effectively in higher conductivity water and larger streams than backpacks
Confined areas can be sampled
Can accommodate small to larger crew sizes
Coordinating multiple anode deployment increases efficiency of sampling deeper areas
Some models have fine controls and output metering that permit sampling standardization and reduced fish trauma

Cons

More expensive than backpack gear
Larger transport vehicle required (a pickup works well)
Higher output power capacity presents an increased safety concern since the crew is wading
Although portable, equipment is heavier and requires more effort to transport to the sample site and navigate shallow areas
Deploying > 1 anode requires a larger crew size
A greater skill set may be needed as opposed to backpack electrofishing; more complicated anode coordination and maneuvers are possible with barge shockers.
Generator maintenance necessary, more involved than lithium battery care

Barge Electrofisher Anatomy

Barge electrofisher major components

Barge electrofisher major components.

Barge electrofisher major components B

Barge electrofisher major components.

Older barge with anode cable reels

Older barge with anode cable reels.

Barge with plate cathode

Barge with plate cathode.

Barge with skid strip cathode in rectangular shape

Barge with skid strip cathode in rectangular shape.

Hand-held electrode (anode when using direct current).

Hand-held electrode (anode when using direct current).

Electrode Arrangement

The cathode is located on the barge hull bottom, isolated from the hand-held anodes. If only one hand-held anode is used, then the electrode operator and dip netter perform similarly to a backpack electrofishing crew. If more than one hand-held anode is in operation, then the multiple anodes can behave independently or work together side-by-side to sample wider streams like multiple backpacks or make more complex movements to sample confined areas as deeper habitats.

Attempt to maximize cathode surface area. Thus, a larger plate cathode should result in more power allocated to the anodes. Having a larger cathode becomes increasingly important as more anodes are brought into service. This said, the crew must balance cathode design between larger surface area and the logistics of moving through stream habitats.
Cathode surfaces often accumulate deposits. Cathodes should be cleaned from these deposits annually or when and if the total electrode resistance increases by ≥10%.
Hand-held electrodes can be in any shape; common configurations are ring and diamond shaped. Anodes also should be periodically hand-shined by roughened pads.

Generator

Often a 2,500 average Watt generator is used as the power source. There are smaller, lighter generators that can be used instead (e.g., the Honda 2200i which is 2,200 average Watts). This generator will require additional equipment (transformer booster to increase output to 240 V and possibly a filter [talk to an electrofishing equipment manufacturer]).

Control Box

Control box designed for barges

This is a control box designed for barges. It is in use and the output metering is displaying peak Voltage and peak Current. (The shadow cast on the box is from the barge operator).

Control boxes used in barges usually are boat pulsator models but control boxes may be specifically designed for barges.

Operation (Control box settings)

Although Barge controls differ in adjustment resolution accuracy, and metering, more and more barges in the U.S. have control boxes with fine controls and accurate output metering (Amperage, Voltage, and sometimes Power).
To facilitate standardized sampling and care when targeting sensitive species, barges should have:
- a range of waveforms, AC, DC, PDC, and Gated Burst, especially if the barge will be used in a wide range of water conditions;
- fine setting controls, i.e., small increments (as 1 pulse per second);
- independently controlled outputs (e.g., volts and duty cycle); and
- accurate output metering (Amps, Volts at minimum).
To extend the range of water conductivity that can be successfully sampled, purchase generators and control boxes with higher power capacity and AC output capability. This selection of generator size must consider the weight-limiting logistics of transport and moving in stream habitats.

*For additional instructional videos on related topics as electrical waveforms, measuring water conductivity, standardized sampling, trouble-shooting, and safety, see

Electrofishing Essentials Course Resources

Deployment

Two-person crew pulling a barge electrofisher.

Two-person crew pulling a barge electrofisher.

Barge electrofishing samples a segment of stream or shoreline, known as a “pass”

Sample stream segments can be with or without block nets.

Sample stream segments can be with or without block nets.

Barge Operation in the Field

Barge Electrofishing Overview and Setup

Part 1 Barge Electrofishing: Overview, Transport, field setup

VIDEO LINK: https://youtu.be/yJ2erdh8OU0

Operations in the field

Part 2 Barge Electrofishing: Operation in the Field

VIDEO LINK: https://youtu.be/k6QM4Vq4iJA

Fish Workup

Part 3 Barge Electrofishing: Fish Workup

VIDEO LINK: https://youtu.be/a_fZeDMmro4