Yellow toned Amur catfish Silurus asotus collected in Lake Izunuma-Uchinuma, Japan

Abstract

In May 2021, a yellow toned Amur catfish was caught by a set net in Lake Izunuma-Uchinuma, Japan. The catfish was 681 mm in total length, and most parts of its body color was yellow. Dark colored body areas of the catfish increased when reared under dark conditions. In contrast, the area of yellow color on the body of the catfish increased under light conditions. The body color of the yellow toned catfish changed according to its rearing environment．After 100 days of rearing under light condition, the body color of catfish become completely yellow. In lake Izunuma-Uchinuma, populations of various fish species have begun to recover as a result of largemouth bass eradication activities. The yellow discolored catfish collected this time also appears to be as a result of the recovery of the catfish population in the lake.