The relationship between longline albacore Thunnus alalunga and sea surface temperature in the South Pacific Ocean;

Preliminary analyses on the biological features of main catches by longline in the Atlantic Ocean;

Preliminary study on appropriate environmental parameters for bigeye tuna longline fishery in the Indian Ocean;

Analysis on catch rate of tuna longline fishing in the high sea of tropical Atlantic Ocean;

Sampling gear was longline fishing.

In this paper a preliminary analysis was performed on composition of catches obtained by longline fishing in the Mediterranean Sea during fishing seasons of two years May-June in 1995 and late April-early July in 1996.

Economic and technical analysis of super freezing deep-sea tuna long liner;

According to field survey data of Atlantic long-line tuna during July to December of 2002, statistic data of FAO and ICCAT, distribution of fishing-ground and its environment characteristics, biology and resource conditions were analyzed or discussed.

According to the collected literatures and field survey, biological characteristics, fishing conditions and management of long-line fishing of tunas in the Atlantic were analysed.

Based on the structure of tuna long-line fishing ge ar and production practice,the author analyzed the vertical moving activity of two tunas: Thunnus obesus, bigeye tuna and Thunnus albacares, yellowfin tuna, an d the catching efficiency of hooks of fishing gear.