This information is important for making regulation recommendations, stocking recommendations, and a variety of other management decisions. Examples of Fish Survey Methods Electrofishing boats are valuable tools used by fisheries staff to collect fish such as largemouth bass, bluegill, walleye, and many others. The electric current stuns the fish, and they float to the surface to be collected. They are then weighed, measured, and a few scales are collected to age the fish. The fish recover from the incident quickly, and are on their way swimming again in a few seconds.
Seines are large nets with fine mesh that are pulled through the water and up onto shore.
Fish that are in the path are swept up and collected by the mesh. Small fish such as minnows and young game fish are collected with this equipment. Fish scales have rings, similar to those of trees, which are used to age the fish. The scales are pressed between two sheets of a soft plastic acetate. They make a flat impression on the acetate, which can then be placed under a microscope for observation and counting of the rings.