Onizaki Fishing Port in Tokoname City is located in Ise Bay in the central part of the Chita Peninsula in Aichi Prefecture. Blessed with an abundance of nutrients brought from the mountains by the three Kiso rivers of Kiso, Nagara, and Ibi, the area is known as one of the nation’s largest seaweed farming land.
Nori farming (photo) goes into full swing from the “seed” work in mid-September. Mainly on land, a net 1.2 meters wide and 18 meters long is wrapped around a water wheel 2 meters in diameter, and the net is dipped into a tank containing spores as the wheel rotates. The seeded nets are stored in the freezer, and in late October, when the water temperature has cooled, they are placed in holes on poles set up at fishing grounds 100 meters to 2.5 kilometers offshore.
After about a month, the leaves grow into leaves about 20 centimeters long, and then they are picked. At the processing plant, they are sorted, emptied, dried, and shipped in board-shaped “dried seaweed.” The work continues until early April of the following year, when the water temperature, repeatedly picking the leaves that grow from the picking spots.
◆ Japan’s sea water is warm
But something troubling is happening. The seaweed in Isa Bay does not grow into leaves unless the sea water temperature drops below 23 degrees Celsius, but in recent years, due to global warming, the sea water temperature is less likely to drop.
According to the records of the Onizaki Fishery Cooperative, in 1989, stakeout work could start on October 3rd, but in 2019 it started on the 21st of the same month, and last year it started on the 22nd, for a total of 19 days. in the last 30 years As a result, the cultivation period has become shorter, resulting in lower yields.
Even after the net is made, the temperature of the water does not drop enough, causing the nori to take root in the net and be swept away by the rough waves. At Onizaki, we know from past experience that if the water temperature does not drop below 20 degrees by the 17th day after hatching, growth will be adversely affected.
In addition, the active period of black sea bream, which prefers warmer waters, has become longer, and feeding damage has also increased. The turbulence of the Kuroshio Current is also said to have raised the water level in Ise Bay, making work difficult. Climate change continues to worry fishermen.
In 1989, there were 120 nori fishermen in Onizaki, but now there are only about one third of them. “If global warming is not stopped, the lack of successors and the lack of successors may cause further contraction of the nori farming industry. There are also limits to mechanization.” Masaki Hirano, adviser of the Onizaki Fisheries Association, feels that a crisis is growing.
It is estimated that the ocean absorbs 90% of the heat generated by sunlight. According to an analysis by the National Oceanic and Atmospheric Administration (NOAA), in August last year, about half of the world’s sea surface, including the seas near Japan, was covered in extreme temperatures high called “sea heat wave.” Due to the effects of rising temperatures in the interior of the continent due to global warming, the sea surface temperature near Japan has risen by an average of 1.28 degrees over the past 100 years. Global warming is progressing at a pace that is more than twice the global average.
In addition to this, abnormalities under the sea are also increasing.
It’s not just the poor catches of saury, squid, and autumn salmon. Spanish mackerel, whitefish, yellowtail and other fish are heading north from the Seto Inland Sea and Kyushu in search of cool weather. Although the spiny lobster, whose northern limit was in the northern Kanto region, crosses the Tsugaru Strait to reach Hokkaido, the number of “Rausu kelp”, a specialty of the Shiretoko Peninsula that prefers cold water, has declined significantly.
The rocky shores of Kyoto Prefecture’s Maizuru Bay are home to tropical creatures such as the poisonous sea urchin family, the sea cucumber, and the rapidly expanding sea coral reefs of Tokyo Bay, and the growing seas of Okinawa. divers.
A walk along the beach shows that global warming is not the only thing hurting the ocean. Plastic bottles, plastic bags, empty cans, empty bottles, used household appliances, used bicycles… It is noticeable when forests disappear on land, but it is easy to forget the disappearance of the seaweed beds, which provide food for ‘fish and shellfish and known as the “cradle of the sea.”
< The beach looks festive, but there are probably thousands of sardines in the sea. ＞
As I read it now, what this poem from Misuzu Kaneko’s “Taiyori” draws heavily on is the shallowness of the beach, which is very dependent on the wealth of the sea, but does not fully reflect the situation within the sea. I can’t help but think so.
◆ Protecting the blessings of the sea
But, says Mr. Hirano of the Onizaki Fisheries Cooperative, the clues can be found in our daily lives. “The seafood we take for granted on our dinner table today doesn’t have to be the strangest things going on in the ocean.”
First of all, I want to think about what I can do from the table. Today is the day of the sea.
at