The Yomiuri Shimbun The catch volume of blue crabs in Sendai Bay and nearby waters off Miyagi Prefecture has been rapidly growing after the 2011 Great East Japan Earthquake, with some experts saying the tsunami contributed to changing the fishery environment.
The nation’s largest volume of blue crab catches has been recorded there since 2015, increasing by more than 300 times.
It is believed that the rising sea temperatures and accumulated mud on the seabed as a result of the tsunami created an environment hospitable to the crabs, bringing unexpected joy to many people engaged in the fisheries industry in the area.
Before dawn on Sunday in Shichigahama in the prefecture, fishing vessels arrived back in Shobuta fishing port one after the other laden with blue crabs.
“Even if we are trying to catch flounder, crabs are getting caught with them,” said Jinei Abe, a 68-year-old fisherman with 50 years of experience on the sea. About 200 kilograms of blue crabs were caught in a gill net set at depths of 28 meters in the sea, he said.
Abe first noticed the abnormality sometime in autumn 2011.
His fishing boat was out to sea at the time of the calamity and escaped from harm from the tsunami, which allowed him to resume fishing in the autumn in the same year as the disaster.
Before the 2011 disaster, only a few blue crabs were caught a year, but plenty of them were found in his net and the catch volume started growing rapidly.
The unit value of blue crabs is low, and handling and processing them require a lot of time, but they have become the main catch for fishing in the prefecture because the haul has since remained stable.
According to data compiled by the Agriculture, Forestry and Fisheries Ministry, the annual catch volume of blue crabs in the prefecture totaled 2 tons in 2010, but the figure jumped to 518 tons in 2015, becoming the highest in the nation.
The volume for 2016 totaled 662 tons, accounting for 30 percent of the entire haul of blue crabs in the nation. The crabs are mainly shipped to metropolitan areas, including Tokyo and Osaka.
One factor for the rising number of crabs in the waters off the prefecture, cited by the prefectural fisheries technology center, was the nationwide trend of rising sea temperatures, which contributed to creating an environment in the coastal waters easy for the crabs to thrive.
In addition, mud on the land was carried by the tsunami to shallow Sendai Bay to create an environment suitable for the crabs.
Blue crabs don’t have the same reputation as snow crabs or red king crabs, but the reasonable prices make them popular as their crabmeat is sweet and innards are creamy. They can be tasty after simply boiling them. Blue crabs are also often used as an ingredient in Chinese cuisine, pasta dishes and miso soup, to name a few.
Menya Musashi, a Tokyo-based ramen chain, added a special limited-time item available only in August: ramen served with a whole blue crab caught in Watari town, Miyagi Prefecture.
“We received positive responses from our customers, with some saying the umami of the crabs tasted so well with ramen,” said Jiro Yatogi, president of Menya Musashi. “So we’re planning to come up with new items.”
If the catch volume of the crabs further stabilizes, it could accelerate moves for branding of the crabs as a local delicacy.