The other is surface fishing gear, including purse seine, rod fishing and dragline fishing. The tuna inhabiting the ocean surface are mainly small yellowfin tuna, bigeye tuna and light fish, and their weights range from 5 to 10 kg.
Both tropical and temperate seas (between 40 north and south latitudes) are distributed, and the central concentration area is near the equator. China is mainly distributed in Xisha, Zhongsha and Nansha Islands in the South China Sea, and also in the East China Sea.
Extended data:
Growth habit
The water temperature is between 14℃ and 23℃, and it is densely distributed between 15℃ and 2 1℃. The migration route is closely related to the seasonal variation of ocean currents. It is a typical marine fish, inhabiting the surface layer of 0~20 m and rarely falling into the water layer of 300 m.
Chang Xiqun swims in foreign waters, and its swimming speed is the highest among other tuna. He likes to live in clear water, sometimes accompanied by sharks or other floating objects, and sometimes jumps out of the water as high as 2 meters.
Albacore tuna spawns in 50~60 m water layer, the spawning water temperature is higher than 24℃, and the spawning peak is in summer. The minimum length of sexual maturity is 960 mm, the eggs are floating, and the egg diameter is 0.93 mm Adult fish mainly eat sardines, eels, large crustaceans and small cephalopods.