Sampling Shad in Southern Impoundments
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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).