Output Goal Tables for Backpacks, Towbarges, and Boats

In the movie The Santa Clause, the elves were inundating Santa with new technologies aimed at keeping him safe from extreme conditions.  In response, Santa wanted to know “but what if I fall off the roof?”  In other words, forget for now the advanced gizmos; falling of the roof is the most important and basic issue for his work.  Well, maybe that’s a bit true about our list of blogs.  I think they are well done and address important matters.  Taken together, this list is pretty comprehensive.  That said, in talking with many biologists, a major initial concern is having straightforward guidance for making suitable volt and amp settings given conditions (e.g., water conductivity).   Here’s a brief blog that builds upon and applies information from other blogs to provide example voltage and current output goal tables.  These charts are generated for sampling fish assemblages using common electrofishing gear types.  They are meant as guidelines for setting controls as opposed to strict instructions.

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Instructional Video Links

There are a number of useful instructional videos housed on a server at the National Conservation Training Center (U.S. Fish & Wildlife Service).  The videos, while still valid, are a few years old now, and likely will be updated or supplemented in the next year or two.

Some of these videos are the same as those housed in Vimeo with links listed elsewhere on electrofishing.net.  Depending upon your connection, the Vimeo versions may have better resolution.  However, to access videos on this list, you don’t need an account or password.

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Course Announcement: Principles & Techniques of Electrofishing

Opportunity knocks! The National Conservation Training Center (U.S. Fish & Wildlife Service) is offering an electrofishing course in Carterville, Illinois during October 23 – 27, 2017.  Please see course description, course flier, and registration process below.

Course Description

Often electrofishing sampling is unsatisfactory (low effectiveness, high variance) due to reasons that include equipment limitations, insufficient understanding of equipment function, inadequate electrode design, and a lack of guidance regarding proper settings given prevailing water conditions and target species.  This class addresses these factors and builds skills in participants that will enable them to tackle sampling issues and increase the efficiency and standardization of electrofishing.

In addition, participants learn how to evaluate gear performance and select suitable equipment, trouble-shoot equipment, assess likelihood of fish injury and use approaches to minimize the potential for stress and injury, and provide a safer operating environment for their crews.

This course covers all types of electrofishing gear types including boats, rafts, tow-barges, shore-based, backpack, electric seine, and pre-positioned.

Participants are encouraged to bring their equipment for evaluation which includes analysis of outputs, calibration check, electrode design, and a safety workup. Gear also is used for standardization exercises.

Course Flier:

Electrofishing Training Announcement Illinois Fall_2017

Registration process for non-Department of Interior Biologists:


Field Tool Kit


Things happen in the field, particularly when we are using complicated sampling gears (= electrofishing equipment).  Malfunctions can occur in the electrodes, branch circuits (conductors running from the control box or power source to the electrodes), the power source, or the control box.  Biologists build a lot of their own equipment, wiring boats, electric seines, and the like.  From what I’ve seen, most problems appear in our wiring or construction, but generator problems, and sometimes control box issues do occur.  Fisheries biologists are a resourceful lot.  If given direction, they usually can diagnose the problem at hand and get back to sampling.  With this in mind, Midwest Lake Electrofishing Systems, based in Polo, Missouri, has developed a list of items for a basic field tool kit (see below).  Although the intent is a tool kit for electrofishing boats, this kit applies to any electrofishing gear type.

Many thanks to the crew at MLES.



Course Title: Backpack Electrofishing: Principles and Practices
Course ID: BIO 407
Status: OPEN
Date(s): June 7, 2016: 8:30am – 4:30pm
June 8, 2016: 8:30am – 4:30pm
June 9, 2016: 8:30am – 4:30pm
Location: William Jack Hernandez Sport Fish Hatchery
N Reeve Blvd
Anchorage, AK
Instructor: Dr. James B. Reynolds
Tuition: $945 / $895*
$845 / $795* (Before May 7, 2016)

Find out more.


Course Title: Boat Electrofishing: Principles and Practices
Course ID: BIO-408
Status: OPEN
Date(s): May 10, 2016: 8:30am – 4:30pm
May 11, 2016: 8:30am – 4:30pm
May 12, 2016: 8:30am – 4:30pm
Location: Red Lion Inn
1830 Hilltop Dr,
Redding, CA
Instructor: Dr. James B. Reynolds
Tuition: $995 / $945*
$895 / $845* (Before April 9, 2016)

Find out more.

Testing Equipment: Importance and Recommendations

Testing equipment, particularly current clamps and scopemeters, have a substantial role to play in electrofishing sampling programs.  I was first introduced to this notion years ago by A. Lawrence (“Larry”) Kolz and Jim Reynolds, two people that made substantial advances in the conceptual basis for electrofishing.  Since then, Jan Dean and I have used test equipment in a number of situations, built Excel-based programs to utilize collected information, and have worked on identifying inexpensive yet accurate meter alternatives.

In this blog, I will attempt to describe purposes of testing equipment, some approaches and considerations regarding their use, share a few of our test results, and provide a list of suggested models.

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Setting Doses for Lab Experiments

Experimental set-up for small fish. Picture by Dr. Jan Dean

Lab or tank experiments on fish have been around for decades, beginning with studies of fish behavior in electric fields.  Presently, tank experiments are used for evaluating the effectiveness of candidate waveforms, estimating thresholds for various reactions that assist capture, guidance, and electrosedation, and determining probability of trauma.  While insights gained by lab work, in combination with field trials, can and have improved fisheries sampling and provided insights for risk analysis, there are pitfalls that can sink the ship.  A couple problems that often occur are the rationale for setting dose levels and the actual description of dose levels.  These issues can lead to misinterpretations, inappropriate management decisions, and constrain application of experimental results.  In fact, dose setting is becoming a big issue in electrofishing experimentation.  I have seen studies lately that have used incredibly high doses, in fact extreme overdoses, preventing a connection from the lab to application in the field.  I think the results of those studies are relatively meaningless.  And, most of the disconnect is due to a poor understanding of electric fields generated by common sampling gears and typical exposure times while electrofishing.

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Selection of Electrofishing Equipment

Selection of appropriate gear types and models is frequently a difficult task. Often decisions are made with little basis.  Here we highlight some factors that we think should be considered when selecting or purchasing electrofishing gear.

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Considerations for Water Conductivity Meters

Determining water conductivity is critical to improve the efficiency and precision of electrofishing sampling, for electrode design, and even as an input to deciding which control box model to purchase or which equipment type to use. Water conductivity has much more value than simply a number placed in a table for completeness.  Reasonably accurate measurement of water conductivity is essential.

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