Gear efficiencies in the fish component of the long term resource monitoring program: predicted versus observed catch

Abstract

Abstract : Environmental monitoring programs are frequently designed to track changes in key physical, chemical, and biological features of an ecosystem. As such, these programs provide critical information for detecting changes in system state, investigating mechanisms associated with observed changes, and making resource management decisions. Because monitoring programs require significant investments of time, money, and human resources, periodic evaluations of monitoring programs are necessary to determine if the sampling design adequately addresses program goals and objectives. Periodic evaluations also permit assessment of a program's ability to provide adequate and useful information for changing management and science needs. In 2001, the author evaluated the Long Term Resource Monitoring Program (LTRMP) sampling design for fish on the Upper Mississippi River System by analyzing data from stratified random samples collected during 1993-1999 in six Resource Trend Areas (RTAs). Specifically, he investigated whether the sampling design could provide nearly the same amount of information it presently does with fewer sampling gears. The project's goals were to assess information provided by each gear used to monitor fishes in the LTRMP, engage program partners in a discussion of the relative value of each gear within the present sampling design, develop alternative sampling designs based on simulations of historical program data and expert opinion, and optimize the implementation of various alternative designs. Following his investigation and consultation with program partners, the author eliminated 4 of the 10 gears used since program initiation in 1989. Results and recommendations are in Ickes and Burkhardt (2002); available at http://www.umesc.usgs.gov/documents/ reports/2002/02t001.pdf.