Tagging

Picture22Members of the Association have participated in both conventional and satellite archival tagging studies for many years, collaborating with the Department of Fisheries and Oceans, Science Branch and with American researchers.

 

Picture20Satellite tags are tiny waterproof computers, which are attached to tuna to record light levels, salinity and depth.  After a pre-programmed time, the tags detach from the fish and float to the surface, where they relay their data to passing satellites. The data allow scientists to reconstruct the paths of the fish; the results of which support strong linkages of Canada’s bluefin tuna to the Gulf of Mexico.

 

Picture19Conventional tags remain with the fish until they are caught again and provide information on the location and size at first capture and at re-capture, providing key information on growth rates. Age-structured studies of bluefin tuna’s growth and mortality provide critical information for stock assessments. With an accurate measure of the age of bluefin tuna, related to size, fisheries managers and scientists can understand growth rate, better assess the abundance and productivity of adult stocks, and predict future numbers.