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Standardization of Great Lakes acoustic ground-truthing workshop

The Acoustic User Group recently develop a standard operating   procedure for collecting and processing acoustic data. The goal of   this standardization was to make comparisons of acoustic fish   densities across lakes directly comparable. Several approaches have   emerged for apportioning acoustic densities to species using data of   fish composition collected with trawls and other traditional fishing   gear.  Ideally, species-specific density and biomass estimates   should also be directly comparable.  It was with this goal that we   developed our latest Science Transfer proposal.    During summer 2 1  we will convene our work group to conduct a   workshop to explore the need to standardize methods for apportioning   acoustic density and biomass estimates to species.  We will invite   subject experts to share their current methods of apportionment.     Our plan is to work in teams and apply at least four presently-used   apportionment methods to at least two acoustic density and midwater   trawl catch data sets.  If the 95% confidence intervals of one   method encompass the mean estimate of the other, and vice versa, we   will deem that the two methods provided similar results.  We will   work to understand the cause of differences we find.      Another way of assessing the performance of different apportionment   methods is to apply each method to simulated populations of   predetermined average density and biomass.  These simulated   populations will consist of known numbers and sizes of commonly   found species including rainbow smelt, alewife, cisco, and bloater   distributed in 3-dimensions and in multiple strata.   We will then   sample these fish using a simulated acoustic survey and simulated   midwater trawls will be fished throughout the study site.  Teams   will be provided the simulated density estimates, target strength   distributions and midwater trawl catches needed to apply the   different apportionment methods.  An apportionment method will be   deemed robust if the 95% confidence intervals encompass the true   abundance and biomass of each population.  If a given method of   apportionment fails to encompass the truth, we will invest effort to   understand the factor(s) causing any discrepancies.    Using results of the analyses, we hope to reach a consensus on 1)   the need for standardization, and 2) the apportionment method(s)   that seem to hold the most scientific merit. 

In progress
Start Date
End Date
Dan YulePrincipal Investigator
Associated with 2 projects
Dan YulePrincipal Investigator
Associated with 2 projects
Lars G. RudstamResearcher
Associated with 3 projects
Randall ClaramuntResearcher
Associated with 1 projects
Patrick KocovskyResearcher
Associated with 1 projects
Larry WitzelResearcher
Associated with 1 projects
Bernie PientkaResearcher
Associated with 1 projects
USGS-Great Lakes Science Center $ 8,025.00USDEstimates

Funding 2 projects for a total of $8,025.00
Scope of Study
Literature / Existing Data
Scale of Phenomena
Resource Management
Lake Basin Connecting Channels
Lake Erie
Lake Michigan
Lake Superior
State Province
Annex Numbers
Surveillance and Monitoring

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