Thursday, June 25, 2009

Electrofishing – Creating the Perfect Management Plan

Electrofishing – Creating the Perfect Management Plan
By Nate Herman www.hbpondmanagement.com

I have not been able to get out my fishing rods nearly as often as I envisioned when I first started stocking fish and managing lakes back in 2003, but during the last couple years I have definitely caught more and bigger fish than I ever dreamed possible! Although I don’t get to use my rod and reel much, I am still able to get my fishing fix by utilizing a variety of sampling and angling methods. By far my favorite fishing technique would have to be correctly utilizing 1200 to 1800 watts of DC electrical current.
After practicing and experimenting for a few years, I have learned how to fine-tune the pulse rate, duty cycle, voltage and amps along with the unique conductivity of the water in a lake to safely draw certain species of fish right up to the anodes of my electrofishing boat!
Not only has electrofishing become one of the most fun parts of my job, but if often is the most important. This method of fish population analysis is a crucial step to creating the perfect fish management plan for a body of water. It is important to take a complete inventory of what you have before making any decisions of what fish to stock or harvest. Some other commonly used forms of fish population analysis are traditional angling, angler surveys, seining and trapnetting. I always try to utilize as many of these methods as possible to obtain the most accurate and complete fish population analysis, but I would say that the electrofishing results are the most unbiased and accurate.
Just about every day I get asked several questions about the electrofishing process. The answer to the most often asked question is NO! When I turn on the electrical current, all of the fish in the lake DO NOT float up to the surface. Only the fish within our approximately 20 foot wide by 40 foot long electrical field are stunned for a very short time. The two guys in the front of the boat need to have good eyes and quick reflexes to capture them before they swim away. For those wondering about the process of electrofishing I am going to describe the equipment, process, capabilities and limitations of electro pond shocking. But before I get into the meat and potatoes of electrofishing, I would like to briefly mention the process of creating the perfect fish management plan.
When I create a fish management plan for a client, it is geared 100 percent completely for that individual client. There are no absolutes in regards to managing fish! Ponds and lakes are definitely unique from each other, but what I have found is the most important and often most overlooked aspect to successful pond management is the fact that every owner is unique from the next! If I give out fish management recommendations before having a client answer some important questions, I am essentially managing that body of water to suit my goals, not his. For that reason, I will not give out any fisheries recommendations without first having a client answer the following questions: What do you want to use your lake for? Who will be primary fisherman? What kind of fish would you like to catch? How often do you plan on fishing? How many and what kind of fish would you like to harvest? Do you plan on supplementally feeding? What is your budget and timeframe? Clearly defining your goals by answering these questions is the most important step to managing your fish!
Once the goals have been defined, we talk about the history of the lake. When was it built? When were the fish stocked? What types of fish were stocked? How is the current status of the fishery? And etc. Once we have gathered as much information as possible, we then get out on the water to assess the current conditions. We analyze the water clarity, quality, chemistry, depths, watershed, vegetation and the fish currently present! All of this information needs to be defined, calculated, and considered when formulating your perfect fish plan. The bass/bluegill/catfish pond is quickly being replaced by specialized fisheries geared towards certain species or goals!
Now that I got all of that out of the way, I will attempt to explain the equipment and process of electrofishing. The boat we use is a custom welded all aluminum, extra wide, 14-foot plate boat with a 25 HP Mercury. We have mounted a special DC generator that powers the DC control box, anodes, and foot-pad. The anodes are mounted to 12-foot long poles and extended out in front of the boat. The electrical current is converted in the control box and sent into the water through the anodes. Our control box regulates how much and how fast the electricity is put into the water. One of the guys on the front of the deck has to be standing on the foot-pad in order for electricity to be put into the water. If he steps (or falls) off the boat, the electricity immediately shuts off. Also in the boat we have a couple 10-foot long dip nets for scooping up the fish, and a 150 gallon fish tank for holding the captured fish.
That’s the basic equipment and although it sounds complicated, it is fairly basic to run. The tricky part is figuring out how conductive the water is and where the fish are? Every body of water carries electricity different from the next. It usually takes a few minutes to get all the settings adjusted to create the best electrical field possible. Once I got the field just right, we have to actually find the fish! This is where the major limitations of electrofishing come into play. Any avid fisherman will learn what general vicinity his target species will be at during the different seasons and even throughout the course of the day. Just like traditional fishing methods, some days of electrofishing are better than others. If the fish are deep, they are not very easy to electrofish!
Several factors that need to be considered when electrofishing would be the time of year, current weather, barometer, air temperature, water temperature, water clarity, depths, and fish structure. In the spring and fall, I prefer to electrofish in the late afternoons when the water temps rise a few degrees throughout the day, and in the summer I prefer to electrofish at night when the fish move up to the shallows to feed. Also I don’t even bother electrofishing after a massive cold front or storm. Even though we can bring up just about any fish we find, we still have to find the fish! Have you ever heard the phrase 90 % of the fish live in 10% of the water? I would probably argue that it is closer to 95% and 5%.
I typically will just start out electrofishing around the shoreline and keep my eye out for any fishy looking area, activity, or developing pattern. We simply have the generator and control box turned on and drive around until we start finding and dialing up the fish. The two netters in the front will scoop up every fish they possibly can and we will spend as much time electrofishing as necessary to gather up a tank full of fish for analyzing.
Typically a 10-acre lake or less, we can collect hundreds of fish in less than 30 minutes of electrofishing. Once the fish are collected, they are weighed, measured, tagged, filmed, and then gently released back to their homes.
Hopefully this information helps clarify the process of electrofishing a bit, as well as help you realize that you don’t have to manage your lake or pond how farmer Joe or some book tells you to. The absolute best thing you can do is define what you want to manage your body of water for, and determine what inventory you already have to create and implement your perfect management plan! Just keep in mind there are no absolutes, but there are certain limitations throughout the entire process. Raising fish is not about the destination, but the journey!

2 comments:

  1. Good article, thanks for writing it. How many people do you usually have on your boat helping electroshock fishing?

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  2. Great one..
    How can i bought the electro fishing device ?
    Can I pay using paypal ?
    Please give me more info about the device.
    Thank you.

    ReplyDelete