Greetings from Blessed Bayou! As we gear up for a fall with a much-appreciated respite from the intense heat of the summer, we are excited to ramp up our electrofishing surveys. The cooler temperatures make fish more able to explore more habitat during the day. By this, I mean that they aren’t as limited to avoiding the heat by staying in the deepest areas of your lake or pond and are therefore more likely to be more evenly dispersed in your lake or pond. This is very beneficial to us and our equipment, as the strength of electrical current wanes with increased depth because it has to travel further under the water. If you are interested in an electrofishing survey but have some questions about what it is that we do during our surveys or how our equipment works, read on to learn about this useful tool that provides the basis for many of the recommendations we make to improve water bodies.
Electrofishing, sometimes called electroshocking, is a survey method used by aquatic specialists in both the public and private sectors of freshwater aquatic resource management. This process involves sending electric pulses into the water to temporarily stun the fish. The rays that protrude from our bow and into the water act as the anodes of the electrical circuit (positive end), while our boat itself acts as the cathode (negative end). The electrical current passes through the water due to the ions present in the water, which are capable of conducting electricity. Fish that come into contact with the electrical current we generate essentially lose control of their muscles, swim towards the rays that we have in the water, and then become immobilized long enough to be netted. We are able to control electrical parameters such as voltage and frequency of the pulses we send into the water via a “shock box” that sits on our boat and is powered by a generator. These parameters are modified based on the water chemistry in your lake, such as the conductivity of your water, which we test on site. At Blessed Bayou, we are trained to make sure to emit an amount of electricity that neither kills nor sterilizes your fish.
One thing important to remember about our survey is that it is just that: a survey, not a census. We are able to usually get around 10-15% of fish in your lake, but due to unbiased collection of shocked fish, we are able to utilize ratios of collected fish to project the inhabitants of your lake with relatively high accuracy. Besides measuring each collected fish, we record the weights of each collected bass. By comparing your fish to the average weight of bass of that length within the state of Texas, we are able to get an idea of how healthy the bass in your lake are, a metric referred to as “relative weight”. While there, we also check fish for presence of external parasites or noticeable diseases to make sure that you have no infectious organisms in your water body. During our survey, we check water parameters including conductivity, pH, temperature and turbidity and take an additional water sample that we bring to a lab for testing other parameters including alkalinity and water hardness. We are also able to offer bathymetric mapping services as well during the survey, helping you gain a good sense of the depths of your lake and pinpoint areas that may contain more fish or areas where structure could be placed.
An electrofishing survey is therefore a way to take a holistic look at your lake to understand the health of your lake with regard to everything from fish sizes and abundances to the presence of unwelcome guests such as harmful algal blooms and parasites. You are more than welcome to accompany us on our survey to see the process firsthand and help us net fish during our survey if you so choose. We only kindly ask that you respect the directions of the Blessed Bayou employees operating the equipment to keep everyone safe and secure during the survey. If you have any further questions regarding our survey process, the concept of electrofishing, or to schedule an electrofishing survey, please don’t hesitate to reach out and we will be able to provide further information for you.