The season for funa-zushi begins around April, and to make it you first remove the scales and gills from some nigoro buna (other crucian carp varieties can be used as substitutes) and then split its belly to gut it, keeping the ovaries, if present, intact.
4月頃、ニゴロブナ（他のフナで代用も可）のウロコとエラを取り、腹開きにして卵巣以外の内臓を除く。