Electronic tags reveal movements, behavior,
and physiology of pelagic fish
Barbara Block, Ph.D.
Hopkins Marine Station, Stanford University
Wednesday, June 12, 2002
3:00 p.m.–Pacific Forum
Electronic tagging technology is currently making possible the tracking of marine animals over vast distances in the open ocean. The successful deployment in recent years of pop-up satellite tags and archival tags on fish has allowed us to examine migrations of oceanic vertebrates that remain submerged and rapidly improved our ability to determine where large, highly migratory fish go. When biological and physical data from the tags are combined with information about sea surface temperature and ocean color from remote sensing technologies, the relationship between movements and behaviors of organisms can be linked to oceanographic processes. These new techniques provide the major advances necessary to understand the distribution of pelagic fish in relationship to their changing physical and biological environments on daily and seasonal time scales. The talk will focus on our use of electronic tags to document the feeding and breeding migrations of Atlantic bluefin tuna. Additionally I will describe a new program called Tagging of Pacific Pelagics that is a pilot project for the Census of Marine Life. The Pacific demonstration project will describe patterns of movement and behavior of marine vertebrates and squid in the North Pacific. This project will use the tag-bearing animals, as autonomous ocean profilers, to define the oceanographic regions of critical interest. The temporal and spatial data generated by our project should provide an “organism-eye” view of Pacific oceanic regimes.