Research was done in crossbreeding between species of differing characteristics, which resulted in success in 1964 between a female red sea bream and male black sea bream. Since then, other crossbreeds have been produced from various combinations.
A red sea bream that is far superior to wild red sea bream was bred by a repeated process of selecting young fish of good form, raising them and selecting from that school of the better quality fish.
The Aquaculture Research Institute has successfully cloned red sea bream and feminized Japanese flounder.
Research is underway into masculinizing tiger puffer and other species.