A General Guide for Deriving Abundance Estimates from Hydroacoustic Data








Target species or groups

Important information on survey needs can be gained by clearly identifying the group(s) of interest.  In the Great Lakes, these groups may include:

  • specific species (e.g., alewife, rainbow smelt);
  • age-classes or age-groups (e.g., age-1, yearling-and-older, young-of-year), or;
  • fish within particular bathymetric regions (e.g., open water, bays).

    By identifying survey targets a priori, we can also identify data limitations that may result from the survey design.  For example, a survey designed to quantify open-water pelagic species may have insufficient nearshore estimates for a future analysis of shallow young-of-year.  These restrictions should be made explicit for the sake of other researchers who may use the data in the future.