Poor quality fishing in many lakes and ponds is caused by unbalanced and/or undesirable fish populations. To determine the status of a fish population, the lake manager must take samples to assess the species composition and size distribution in the lake. You can use one of several methods to sample fish populations, including partial rotenone treatments, electroshocking, gill netting, trap netting, shoreline seining, and angler catch records.
Although the first four techniques can provide excellent information, they are not practical for most lake owners. As a result, most pond owners rely on shoreline seining and angler catch records for making management decisions, and this is recommended. Shoreline seining is a good technique for assessing the status of many fish populations.
To collect fish population data using the seine method, seine during the months of June or July. A 15×4 foot minnow seine with a ΒΌ-inch mesh is good for most lakes and ponds. Seining provides information on the presence and reproductive success of largemouth bass and bluegill. Excessive aquatic vegetation and brush will make seining difficult. Make a minimum of three quadrant seine hauls (more in larger lakes) in different areas to collect a representative fish sample from shoreline habitat. Record the numbers and sizes of each species collected for each seine haul.
Angler catch records can also be used to gather lake management information, which often provides information on species not easily collected by shoreline seining. It sounds like fun, but to collect meaningful information, anglers should fish regularly with a variety of lures and baits (to catch as many of the species as possible) or fish consistently with similar gear from year to year (to identify changes in length and abundance).
Assessment using angler catch records is only as good as the information collected. Therefore, make an extra effort to record the numbers and lengths of all species caught, along with other pertinent observations. Definite trends in harvest composition will become apparent over time, providing you with reliable information necessary for making sound fish and lake management decisions.
Research has found a strong correlation between sport fishing and electrofishing data in largemouth bass populations, when Proportional Stock Density, Relative Stock Density, and relative weight values were compared.
Related Articles on Fish Surveys and Sampling:
- Hook and Line Sampling
- Seining to Survey Fish in Your Lake
- Electroshocking
- Proportional Stock Density