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Canadian fishery scientists, as recommended at the Fourth 

 North Pacific Albacore Workshop (NPAWS), to intercal ibrate 

 and evaluate the otolith daily ring increment and fin 

 ray circular methods for ageing albacore. 



2) Stock Structure $tudies- -These studies are being conducted 

 to determine if the North Pacific albacore population is 

 composed of more than one substock, as has been indicated 

 by results from the cooperative NMFS/AFRF tagging program. 

 The studies are being conducted using data on tag release 

 and recovery, and size composition. In addition, samples 

 have been collected for biochemical investigation (to be 

 done at Scripps Institution of Oceanography) as recom- 

 mended at the Fourth North Pacific Albacore Workshop. 



Migration Studies- -These studies are designed to examine 

 albacore migration on trans-oceanic macroscales and within region meso- 

 scales. They are related to 1) the investigation of stock structure and 

 the distribution of proposed substocks of North Pacific albacore, and 2) 

 albacore oceanography studies which investigate the role of environmental 

 factors and conditions that influence the timing and rate of albacore 

 migrations. These studies are conducted using data on tagging and release, 

 size composition data, fishery-oceanography data gathered from cooperating 

 fishing vessels and research cruises, and results from acoustic tracking 

 experiments. 



Environmental Physiology Studies- -These studies are 

 designed to gain understanding of albacore physiological/biochemical 

 processes, with an emphasis on thermoregulation and the role that it may 

 play in understanding causal factors operating in fish-ocean rela- 

 tionships. The studies are carried on cooperatively with fishery 

 physiologists and medical research scientists from universities and private 

 research foundations. Experiments are carried on aboard ship with live 

 albacore; in some cases, albacore specimens and samples are collected at 

 sea and analyzed in the laboratory. There have also been attempts to 

 transport live albacore to shoreside facilities and hold them in 

 captivity. Shiptime, limited equipment, and some supplies are provided by 

 NMFS; major equipment and supplies are provided by the individual 

 cooperating scientists. 



Foreign scientists from Japan, Canada and Taiwan are 

 also engaged in related research activities. These include such research 

 areas as population dynamics, migration patterns, oceanography, and growth 

 rates. 



