Scott A. Bonar Lab
AZ Cooperative Fish and Wildlife Research Unit
Relative Length Frequency: A Simple, Visual Technique to Evaluate Size Structure in Freshwater Fish Populations
Project Partner(s):
Project Duration:
Principal Investigator(s):
Research Assistant(s):
Washington Department of Fish and Wildlife, USGS CRU
December 1994 to August 2001
Scott Bonar
Used data collected from standardized electrofishing surveys in Washington State to develop a method to rapidly evaluate the size structure of inland fish populations. "Relative length frequency" compares the length frequency of fish from a particular lake to an average developed for a state or region. This technique is analogous to relative weight (Wr), relative condition (Kn) or relative growth, which are used to compare condition or growth of fish in a particular water body to range wide or regional standards. Relative length frequency can be used in conjunction with relative weight or relative growth to rapidly identify potential factors limiting the production of catchable-sized fish in a population.