The study aims to see the distribution of tuna fish yellowfin tuna (Thunnusalbacares) in the Indian Ocean Section West, see CPUE tuna yellowfin tuna (Thunnusalbacares), variability of chlorophyll-a and the temperature of the sea surface every month and season as well as a correlation to chlorophyll-a and the surface temperature sea against the distribution of yellowfin tuna (Thunnusalbacares) i…