Photo/IllutrationGoldfish improved by Yadoru Kawahara. One on left has a yellowish green hue, and the one on right has a bluish green hue. (Takemichi Nishibori)

  • Photo/Illustraion
  • Photo/Illustraion

SAKADO, Saitama Prefecture--Yadoru Kawahara, 97 years old and revered by fellow hobbyists as the "goldfish wizard," has just pulled off his greatest feat.

The dream that had dominated his retirement years was to breed green colored goldfish, and that is precisely what he achieved.

As to why anyone would do that, Kawahara had a ready answer: "Because there were none."

The effort involved a lot of trial and error, but “I finally did it," said a beaming Kawahara. "I'm so happy I was able to do so in my lifetime.”

Kawahara originally hails from Nagasaki Prefecture. He served as a gunner in the Imperial Japanese Army during World War II and was detained in Siberia after the conflict ended.

Following his repatriation to Japan, Kawahara moved here for work, counting on the connections of a relative.

While employed at a machinery factory, he started keeping goldfish as a hobby. After he retired, Kawahara started breeding goldfish to sell.

His first efforts to breed green goldfish were patchy.

The cross-breeding of goldfish often resulted in offspring that had only one of their parents’ coloring and pattern.

As part of his quest, Kawahara created bright yellow “muse” and long-finned “aurora” goldfish.

In the belief that cross-breeding blue and yellow goldfish would result in green ones, he spent years selectively breeding bluish “azumanishiki” in the hope of creating one with a stronger blue hue.

His rationale was that by using “muse” for cross-breeding, he could eventually produce green specimens.

A goldfish lays about 3,000 roe at a time. The fry are then sorted into "promising" ones and those that aren't. The promising group must have a certain color and pattern as they grow. A steady 30 percent success rate is necessary to qualify as an improved breed.

It was only about four years ago, when his fish started to show noticeable green spots on their backs, that Kawahara realized he might be on the verge of a breakthrough.

Last year, his efforts produced 20 or so fish that were green, giving him a success rate of about 20 percent. This spring, about 100 goldfish turned out green, giving him a success rate reaching 80 percent.

“It took a while to get there, but now suddenly I've got lots of green goldfish,” said Kawahara. “It is one of the wonders of living creatures.”