Kelp grouper farming

The kelp grouper, Epinephelus bruneus, belongs to the family Serranidae and inhabits waters in south of central Honshu.

It is a wintry delicacy as "nabe cuisine" particularly in Wakayama Prefecture, but because of small catches in recent years, it has been called a "dreamlike fish".

The Aquaculture Research Institute began researching the cultivation of kelp grouper in the early 1980s, by first collecting mature groupers and raising them to adults.

The larger groupers of a school tend to change gender from female to male.

Therefore, in 1988, after several years of raising fish to maturity, eggs were produced and artificially hatched to produce the first fry.

However, it took several years until production stabilized because the mouths of the hatched larvae were smaller than those of red sea breams and Japanese flounder, and there were difficulties in procuring feed that was small enough for them.

Moreover, growth was slow during winter when water temperature was low, with the fish reaching only 3 kg in about 5 years, but since they reached about the same size in 3 years at the Amami Station, The cultivation period was shortened by shipping the fry produced in Wakayama to Amami.