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The
paucity of published information on shad sampling methodologies prompted the AFS Southern
Division Reservoir Committee to design a study to determine the relative effectiveness of
several sampling techniques for estimating abundance and size distribution of gizzard shad
and threadfin shad populations. Six sampling methods, including
hydroacoustics, electrofishing, gill nets, rotenone, seines, and midwater trawls, were used concurrently
to obtain data from three sites on Lake Texoma, Oklahoma-Texas, in August, 1991. Shad were
collected to compare density estimates, precision, and length-frequency distributions
among gear types. Sampling characteristics of individual gears also were evaluated to
define sample-size requirements, interpret spatial patterns of shad abundance, and
recommend gear and sampling improvements.
This booklet is intended to provide fisheries researchers and managers
with some general guidelines in developing a shad sampling protocol suited to their
specific needs. Gear-specific results will be presented and recommendations as to sample
design will be made. A detailed description of the methods and results of this study can
be found in a series of eight manuscripts published in the North American Journal of
Fisheries Management, Volume 15(4).
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