There are many difficulties in keeping tuna in captivity, mainly in the following areas:
Survival environment requires high: tuna mostly live in the vast oceanic environment, the water quality, water temperature, salinity and other requirements of harsh, suitable for water temperature of 13-25 ℃, the need for clear, high dissolved oxygen seawater, artificial simulation of such an environment is extremely high cost.
Large demand for activity space: as a fast, long-distance migratory fish, tuna has strong swimming ability and needs spacious space, and it is difficult to meet its demand for activity range in general breeding pools, and the narrow space is easy to lead to its growth obstruction and physical decline.
Special diet: Tuna is a carnivorous fish, mainly feeding on sardines, squid, etc. It is difficult to provide sufficient and suitable natural bait in captivity, and the research and development of artificial feed is also facing challenges, and it is easy to pollute the water quality by feeding a large amount of bait.
Breeding technology is complicated: the breeding habits of tuna are complex, and its breeding requires specific environmental conditions and physiological stimulation, it is difficult to simulate its natural breeding scene under artificial breeding environment, and the physiological mechanism of its reproduction has not been fully grasped, which leads to a low success rate of artificial reproduction.
Slow growth rate: tuna grows slowly, it takes a long time to grow from juvenile to marketable specification, and during this period, it also faces many risks such as diseases and environmental changes, so the long breeding cycle increases the cost and management difficulty.