Image: Reuters Berita 24 English - Takeo Nakajo has been catching katsuo, or skipjack tuna, for fifty years. This essential ingredient in Ja...
 |
| Image: Reuters |
Berita 24 English - Takeo Nakajo has been catching katsuo, or skipjack tuna, for fifty years. This essential ingredient in Japanese cooking can be consumed raw, dry, or used as a soup basis.
He and other fisherman in Kure, Kochi Prefecture, southwest Japan, have noticed an alarming increase in unusually fatty katsuo over the past two years, which is concerning.
Although heavier katsuo means more money, residents and experts say it's a sign of climate change and a concern to the species' numbers, which are already in danger due to overfishing and rising demand.
The 70-year-old Nakajo speculated that the water's temperature might have anything to do with the fatty katsuo. I feel a sense of urgency because I worry about what might happen if Katsuo doesn't visit the bay one day.
Chef Noriaki Ito of the century-old Kochi City restaurant Tsukasa claimed that he had also "never seen such fatty katsuo during this season of the year."
This is concerning because the sea and climatic changes have already wiped off certain other fish, Ito continued, "particularly a shellfish called chambara-gai that used to be Kochi's specialty."
Every spring, some Pacific katsuo that were originally from tropical waters move northward on a warm ocean current, making Kochi's arc-shaped harbour a productive fishing area.
According to statistics from the local fisheries lab, the bay's average winter surface temperature has increased by 2 degrees Celsius over the forty years leading up to 2015. The fatter katsuo may be related to the abundance of prey in the warmer water.
According to Kochi University Vice President and agroscientist Hideyuki Ukeda, in the long run, this warming may prevent mineral-rich water from rising to the surface, causing a decrease in plankton and smaller fish to feed on, which will lead to less katsuo.
This occurs at a time when Japan's ageing population is endangering the viability of the country's fishing industry and industries associated to it, including the manufacture of dried and fermented katsuo and wasabi horseradish, a mouth-watering sauce nestled behind fish in sushi.
According to Takahiro Tanaka, a fourth-generation fishmonger and self-described "katsuo sommelier," many fishermen in Kure, a district of Nakatosa town, have gone out of business in the last three decades.
This location may be one of the remaining villages in Japan where katsuo is still a part of daily life, he continued, because "we can differentiate different flavours of katsuo, just like simple French farmers may savour subtleties of wine."
Tanaka remarked, "But without fishermen, this won't last.
Fisherman Nakajo lamented the community's ageing demographics and lack of successors. I wanted my grandson to take over, but he is currently pursuing a career in government service, Nakajo added.
SUSHI CULTURE IS IN DANGER
The Kochi fishermen who have kept to traditional single pole fishing techniques rather than large-scale seine fishing across the western Pacific have already suffered from overfishing's effects on catch levels.
According to official statistics, Kochi's capture rates are only 1/4 as high as they were in the 1980s.
Over the past 10 years or so, "we have seen a catastrophic decline in landings," said Ukeda.
If things keep on this way, a rising number of individuals worry that we might soon be unable to eat katsuo.
Production of katsuobushi, dried and fermented katsuo that is frequently used as a soup base or as a shaved garnish over traditional Japanese foods, is already in decline.
According to Taichi Takeuchi, who owns a katsuobushi manufacturing business in the town of Usa, there are now only a few left in Kochi, down from dozens some forty years ago.
Takeuchi said, "I'm not sure if we can go on like this.
Similar production issues are affecting wasabi, the pungent horseradish that is a staple of Japanese cuisine, notably sashimi and sushi.
Masahiro Hoshina, 72, the head of the regional wasabi producers' association, claimed that typhoons and rising temperatures had a negative impact on Okutama's wasabi output, a hilly region to the west of Tokyo.
Hoshina expressed his severe concern for the future of his farming.
Due to depopulation, the number of farmers in the region has decreased by 75% since the 1950s, and some people are concerned that sushi itself may be in danger if nothing is done.
As in katsuo and wasabi, the blending of raw fish and spice is an art that must be preserved, according to Ukeda. He continued, "I never want to think about a future without children".
No comments