Block This grant is focused on the use of a new generation of remote technology devices, called pop-up archival satellite tags (PSAT). This study combines physiology, oceanography and engineering to develop technology that will permit studying the migratory movements of open ocean fish. The PSAT tags are essentially computers that record navigational information, body temperature, depth and ambient temperature data. The tag technology will be used in combination with established molecular genetics techniques to establish the relationships between distinct genetic haplotypes evident in certain populations oi pelagic fish and their dispersal patterns in the open ocean. Despite the economic and ecological unportance of highly migratory pelagic fish such as bmfishes (e.g. marlins, swordfish, sailfish) and tunas, little is know about their movement patterns and population structure. The PSAT tags will provide information on how the movements of pelagic fish are influenced by oceanographic factors such as temperature. Although considerable effort has been expended using fisheries statistics, tag and release studies, and acoustic telemetry, the time scale and resolution of these techniques are insufficient to characterize migrations and address questions about life histories and gene flow. This lack of information becomes more critical as fisheries continue to pressure resources. The NSF award will support the development of prototype and first c,,eneration tags, and the deployment of tags on captive and wild tunas. Tracks of approximately 20-30 Atlantic bluefm tuna will be obtained for periods of one-two years. The PSAT tags will immediately illustrate the potential existence and relative importance of migratory corridors and temporal and spatial movement patterns in relation to oceanographic conditions. Until now this has been challenging data to obtain. The information gained will improve our understanding of the biology of these species and increas e our knowledge of stock structure. The successful implementation of the pop up archival tag technology will provide marine researchers with a novel tool for studying inaccessible marine vertebrates.
