Click here to view the video.

Lord Farday fishing the Macquarie River, NSW with generator cowling removed.

The hull is a 3.4m v-nosed aluminium punt design, custom built by Chris Veal and his team at Baldwin Boats, Mildura, Victoria with input from Clayton Sharpe at the Murray-Darling Freshwater Research Centre. Powered by a 50HP 4-stroke Mercury and featuring the following luxuries, the boat is faster and much more stable (albeit no lighter) than the rather agricultural design of FRV PoleVolt:

• insulated generator shroud;
• side console steering with electric tilt & hydraulic steering;
• electric generator start wired into console;
• integrated live-well with fill-pump, overflow outlet, side-drainage and carpeted cover;
• deck wash;
• navigation, deck & spot lights for night fishing;
• 12V accessory port for charging your 3G iPhone (safety first); and
• an OH&S-lovers bow gate (my personal favourite – so civilised!).

On the plane in the Macquarie River, near Warren, NSW.

Burke O’Neill, director of ETS Electrofishing, supplied the MBS-1DP-COL-SR high-peak current control box, developed by Colton Perna for Australian conditions. This unit is designed for nominal 240 VAC, single phase, 50 Hz operation, from a portable alternator – in this case supplied by a 6.5 KVA Honda from Powerlite – and is capable of delivering 4.8 KVA to the electrode system. Unlike the standard MBS-1D, the safety interlock pad/switch on the COL-SR may be used to directly switch the high voltage output on and off without resetting the front panel START/RESET button. In laymans terms, this combines with the full ETS volt and amp metering to provide more effective and efficient fishing than the 5.0 GPP Smith-Root systems. It’s also about 2/3 the price and user serviceable!

Fishing the Warren Weir pool, Macquarie River, NSW.

Colton Perna completed the wiring of the boat to meet the rigorous Australian standards (which I will post in our resources section the near future), with waterproof safety switches and the ubiquitous quick-release anode fittings. The anode themselves are a relatively new design aimed at eliminating the hassle of setting-up the industry standard Wisconsin arrays – droppers can simply be clipped on and off using the stainless carabiners to change electrode resistance. A new, finger-friendly system of  anode attachment and rotation system, designed by Clayton Sharpe, is also fitted – instead of drop-in holding pins, two frilled circular plates mesh together under a large circular nut which can be adjusted while wearing gloves.

A tagged Murray Cod about to be released.

Our biggest teething problems have been with the trailer. Baldwin Boats supplied a Dunbier trailer, with beefed-up leaf suspension and a third-wheel. This set-up is perfect for launching recreational boats on standard concrete ramps into deep water. However, as any freshwater field technician knows, in the world of research these facilities are available at about 5% of sites visited. On the steep, muddy banks of Western NSW, retrieving Lord Faraday is quite an undertaking, especially if the trailer and boat need to be retrieved from the bottom of a steep bank separately (as is sometimes the case) – the extended corners of the front deck mean that the trailer has to be tilted skyward and the boat scooped onto the trailer, otherwise the deck corners smash into the trailer lights. The deck is also wider than the side skids which hug the hull once the boat is fully retrieved. Lastly, the roller adjustment stems hang down too far, which reduces 4WD clearance dramatically for no reason. We’re currently adjusting the set-up to resolve these issues.

A 3rd wheel winch launch at Warren Weir, Macquarie River, NSW.

Overall, Lord Faraday presents a big step forward in small boat design for Australian river and wetland electrofishing operations. So many great features have been packed on board, while still providing ample space for other gear and a 2- or 3-person crew. Once adjustments to the trailer are complete, I think one would be hard-pressed to find a slicker unit on Australia’s waterways (mind you, I’m slightly biased).

The software is essentially a Microsoft Excel file with a series of macros which enable users to calculate their power outputs given their gear specification and settings. Version 1.41 includes a revolutionary equipment capacity page which begins to answer the question that all electrofishing users should be asking, ‘Can my equipment actually catch the fish that are here?’.

Download the manual.

Download the software.

Dr Alan Temple, from the USFWS National Conservation Training Center will be teaching the course, assisted by Colton Perna. The course will consist of two days of classroom-based teaching focusing on electrofishing theory and safety, plus a day of field-based demonstrations and hands-on teaching – possibly at nearby Centennial Park.

The cost of the course will be AUD $1000 per person, including catering of lunch, morning tea and afternoon tea (payment details to be announced soon – either by UNSW invoice or credit card). Accommodation is
available close to the UNSW campus, or near Central Station (20 minutes by express bus).

Please register your intent to attend (or a list of attendees from your institution) by email to thomas.rayner@unsw.edu.au. The course will be limited to 30 students. If there is sufficient interest, a second course may be held during the following week, 2 November. Participants that successfully complete the final exam will receive a certificate from the USFWS.

See you there,

Tom Rayner.

We can offer the online training to anyone anywhere and we can offer the field practicum at your location based on a minimum enrollment (5+ people in order to re-coop some travel costs of the instructor). This course is recognized by Fisheries and Oceans Canada. This course does not meet the provincial regulations that exist in BC, and not does it meet the requirements of OMNR employee training – all others may take this course.

We have course fee reductions for First Nations groups and NGOs – please contact the CRI Training Coordinator for more information: Michelle Gray m.gray@unb.ca.

Course information also available at:

http://www.unb.ca/research/institutes/cri/opportunities/courses/electrofishing.html

Both the boat and backpack versions are three-day courses, with most
of the middle day devoted to getting hands-on experience in the field.
These will be the public course dates for this year:

BACKPACK electrofishing, March 23-25 in Santa Cruz, CA
http://nwetc.org/bio-407_03-09_santa_cruz.htm

BOAT electrofishing, May 20-22 in San Antonio, TX
http://nwetc.org/bio-408_05-09_san-antonio.htm

BACKPACK electrofishing, September 15-17 in Vancouver, WA
http://nwetc.org/bio-407_09-09_vancouver.htm

Full details and online registration forms are available through the
links above.

About the Instructor:
Dr. James B. (Jim) Reynolds is Professor Emeritus of Fisheries at the
University of Alaska Fairbanks where he served on the faculty during
1978-1999. Jim is a recognized authority on electrofishing and ecology
of northern fishes. He has taught electrofishing short courses to over
1,500 biologists in the U.S. and Canada, is the author of the chapter
on electrofishing in “Fisheries Techniques” published by the American
Fisheries Society and has written numerous research articles on the
subject. Jim is Past President of the Education and Fisheries History
sections and Missouri and Alaska chapters of the American Fisheries
Society. He also provided technical guidance for the NOAA Fisheries
electrofishing guidelines (see link above). Other instructors will
assist during the field portion of the class.

Registration:
$695 (*$595 reduced tuition available for Native American tribes;
government employees; nonprofits; students; and AFS, NAEP, NEBC, NWAEP
members).  Group discounts are available for any organization sending
more than one person – email me for details.  You may register via the
URLs above or by calling the Northwest Environmental Training Center
at 206-762-1976.

For many practicioners, however, electrofishing remains very much a dark art. This is understandable given the “very dynamic and complex mix of physics, physiology, and behavior” at play, but we must not fish without thinking. We must not fool ourselves into a false sense of security regarding (a) the scientific validity of our sampling or (b) the potential effects on fish health. Instead we must ask: are we hurting fish; if so, how so; and, if so, is the level of harm justifiable when compared to other gear types and the positive conservation outcomes?

In his 2003 report, Darrel Snyder, Colorado State University, began answering some of these questions, by first detailing the mechanics of electrofishing using field and power transfer theory, together with fish models. He then investigated the evidence relating to fish injuries in two main categories, non-spinal internal injuries and spinal injuries, and reviewed the response thresholds for various North American species, mostly salmonids. He found the latter group to be particularly susceptible to alternating currents. Direct current (DC) and low frequency pulsed DC (<30 Hz, the lower the better), in contrast, caused fewer spinal injuries and hemorrhages (p.98).

Hemorrhages and associated tissue damage in a rainbow trout (source: N. G. Sharber).

Snyder also discussed the relationship between the spatial characteristics of electric fields and fish injuries. He suggested that reducing the area of most intense power (near the anode/s) may not reduce fish injuries, if the threshold for injury is, in fact, occurs at much lower powers (i.e., towards the outside of the field where fish exhibit a twitch response). He concludes:

Except in very severe cases, electrofishing injuries in fish heal and seldom result in immediate or delayed mortality. Instead, most electrofishing mortalities appear to result from asphyxiation due to extended tetany or poor handling. However, electrofishing injuries may significantly reduce subsequent growth, at least until they fully heal. When sufficiently severe, spinal injuries may affect physical appearance or swimming ability. Still, even for highly injury-susceptible species, such as the salmonindae, significant effects at the population level are unlikely except in the case of very small or very extensively and intensively sampled populations, as is sometimes the case for threatened and endangered species.

Electrofishing is a valuable tool for fishery management and research, but when resultant injuries to fish are a problem and cannot be adequately reduced, we must abandon or severely limit its use and seek less harmful alternatives. This is our ethical responsibility to the fish, the populace we serve, and ourselves.

Like the subject matter itself, Snyder’s text is complex. But, for experienced practicioners wanting to be more honest with themselves, this report is a great place to start. Can you address the knowledge gaps identified by Snyder as an add-on to your existing sampling?

Download Snyder’s report here.

The top photo shows a dorsal view X-ray of a rainbow trout revealing spinal fracture caused by electrofishing (source: N. G. Sharber).

The new vessel will boost research programs being run in the two labs, including fine-scale responses of fish to environmental flows in arid-zone rivers and wetlands, such the Macquarie Marshes, and Australian Bass stocking and monitoring in coastal NSW. It may also be used for studies of electrofishing methods and effects on fish, plus external contract projects in the future.

With such a diverse range of projects in mind, we’ll need a shallow-drawing hull that can still deliver plenty of power and be used in the more open waters of the State’s larger impoundments. We’re thinking of either a flat-bottomed punt similar to NSW DPI – Fisheries’ PoleVolt&lt or a v-nosed flats boat like those used in the Florida Keys to chase Tarpon. An electrofishing boat built around the latter platform would probably be a world first.

An aluminium cat hull could be a seriously fast and effective electrofishing platform. Image: www.flatscat.com

Colton Perna, from the Australian Centre for Tropical Freshwater Research, will be advising the research team throughout the build and Dr Alan Temple, an Instructor at the U.S. Fish & Wildlife Service National Conservation Training Center, will visit UNSW in September 2009 to conduct an electrofishing  training course. The course will be open to all fisheries research and management professionals in Australia and NZ, with further details to be posted in the next couple of months.