Ito Fish Battle for Spawning in Kushirogawa River
The Kushirogawa River in eastern Hokkaido is witnessing the final days of the spawning season for the critically endangered ito fish, also known as the Sakhalin taimen. These majestic creatures, among the largest freshwater fish in Japan, are facing an uphill battle for survival.
Their natural breeding grounds are limited to Hokkaido and the Northern Territories, and only a handful of rivers have confirmed breeding activity. The International Union for Conservation of Nature and Natural Resources (IUCN) has designated them as "critically endangered," while the Japanese Environment Ministry classifies them as "endangered."
This April, an Asahi Shimbun reporter witnessed a rare and fierce battle between two male ito, each exceeding a meter in length, vying for the attention of a female. During the spawning season, the males' bodies, except for their heads, turn a vibrant red.
However, the fight for survival extends beyond inter-species competition. Local government road construction upstream has resulted in a deluge of sediment reaching the spawning area, jeopardizing the hatching of the fry.
The reporter observed a male and female pair as a rival male approached, following the meandering current. A sudden splash marked the start of a fierce battle between the two males. The paired male positioned himself protectively over the female, preventing the rival from making contact.
The rival retaliated by flipping his body and biting the other male's torso. The fight raged on in shallow water, their bodies mostly exposed to the air. It was a desperate struggle for dominance, lasting for several tense seconds.
Amidst this fight for survival, a symbol of resilience emerged. Yellow fuchsia, known as "chiraiapappo" by the indigenous Ainu people, bloomed on the shore, offering a poignant reminder of the enduring beauty and strength of nature.