You may have heard of fly-fishing or spearfishing, but electrofishing? Electrofishing is a common way of fishing that is used by fisheries biologists. They use electrofishing to sample the fish populations in freshwater. Electrofishing is by using electricity to catch fish. Electrofishing boats or small backpack shockers create the electricity.
Why Electrofishing Is Used
The biologists shock the fish before they are caught. They are shocked so they are easier to catch without harming the fish with hooks. Biologist use the method of electrofishing to determine
- Species Composition
- Age distribution
- Presence of invasive species
The different types of pulses depend of the size and nature of the catch. In order for electrofishing to be effective it has to be influenced by technical, logistical, biological, and environmental factors. The stronger the electric field and pulse the bigger the fish will be able to be caught.
How Electrofishing Works
There are three types of electrofishers.
Backpack electrofishers are gas or battery powered. These work by employing a transformer to pulse the current before it’s delivered into the water. They also have safety features like speakers that make sounds when the unit is operating, quick-release straps, and tilt-switches if the backpack is tilted more than 45 degrees.
Boat electrofishing is when the boat itself is a cathode with the anodes mounted on the bow. The boat makes the fish swim towards the bow and are caught with a dip net.
Another method is available but not prevalent is by illegally diverting electricity from overhead electric lines. This is dangerous and can cause electrocution.
- Fish will not be affected by electrical fields if the waters are turbid.
- Only electrofish with backpacks in waters that are knee deep to prevent any drowning.
- The more skilled a team, the more fish that will be caught that are not harmed.