Photo/Illutration “Ido Medaka” killifish nurtured by Arimune Munakata, an associate professor at the Miyagi University of Education (Asahi Shimbun file photo)

In February 1999, the Environment Agency (the present-day Environment Ministry) shocked the nation by designating the all-too-familiar “medaka” killifish as an endangered species.

That was exactly a quarter-century ago. Has the medaka population grown or declined since then?

“Unfortunately, the medaka’s risk of extinction is growing,” said ichthyologist Arimune Munakata, 51, an associate professor at the Miyagi University of Education. “Although preservation measures have proven successful in some regions, many of their habitats have been lost.”

He continued, “If we provisionally set the medaka population at the end of the Edo Period (1603-1867) at 100, the population today has been reduced to less than 10 due to pesticides and invasive foreign species.”

Munakata has been working to revive schools of wild medaka that carry genes unique to natives of the Sendai area.

They were believed to have been driven to extinction by the tsunami triggered by the Great East Japan Earthquake of March 2011.

But it so happened that the year before the quake, researchers at Munakata’s university had collected 20 to 30 medaka near the Ido district of Sendai’s Wakabayashi Ward and were raising them in the university’s research pond.

Munakata named these fish “Ido Medaka” after the district they came from. And when he sought volunteer breeders, individuals as well as schools and corporate groups positively responded.

These medaka are black. Munakata held lectures and workshops at a local zoo to ensure that the fish were not cross-bred with red and yellow pet medaka.

“Thankfully, the Ido Medaka population has now grown to the tens of thousands,” Munakata beamed. “They are a symbol of (Sendai’s) recovery from the disaster.”

After my interview with him at his university, I headed by car to Wakabayashi Ward, where many residents perished in the tsunami.

In a pond installed at the former site of an elementary school, the medaka were swimming freely and vigorously. Every individual was beautifully black.

As I watched them, my thoughts turned to animals and plants unique to the Noto Peninsula that must have been washed away by the tsunami triggered by the earthquake on New Year’s Day.

Are there rare species that are now on the verge of extinction? With water service disruptions and power blackouts still plaguing survivors of the Noto Peninsula earthquake, I know there is nothing that can be done yet.

But I pray, at least, that when life returns to normal, people’s attention will turn to the revival of those small endangered lives.

--The Asahi Shimbun, Feb. 13

(This article was carried only in extra online editions for the newspaper holidays)

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Vox Populi, Vox Dei is a popular daily column that takes up a wide range of topics, including culture, arts and social trends and developments. Written by veteran Asahi Shimbun writers, the column provides useful perspectives on and insights into contemporary Japan and its culture.

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