Evaluation of USA and Canadian Research Vessel Surveys for Sea Scallops (<i>Placopecten magellanicus</i>) on Georges Bank

Abstract

Independent research vessel surveys of the sea scallop resource on the northeastern part of Georges Bank were conducted annually by the USA and Canada during 1982-84. Despite differences between the USA and Canadian surveys in sampling design, statistically-comparable estimates of relative abundance, population size composition, and recruitment levels were obtained from the two surveys in each year. Four potential factors contributing to this concordance of results are identified and evaluated with respect to survey design considerations, sampling intensity and future survey activities. Because the information from the USA and Canadian surveys appears to be the same, there would be virtually no loss in accuracy or precision if survey responsibilities were shared on an alternate-year basis. Moreover, since survey ship time is costly, a considerable saving of expense would ensue to both countries from this arrangement.