Three-and-a-half years after Japan’s earthquake, tsunami and nuclear disasters, strong oyster harvests on the Sanriku coast and the re-start of test commercial fishing off Fukushima show the gradual progress of recovery, even as leaks of contaminated groundwater at the reactor continue.
The Sanriku Coast includes Iwate Prefecture, northern Miyagi Prefecture and southern Aomori Prefecture, all on northeast Honshu Island. The coastline is classified as a “ria” coastline because it was formed by ocean flooding of former river valleys when the land subsided. The result is a deeply indented and island-studded coast that offers excellent protection for oyster rafts. Such coasts also amplify tsunamis.
The area accounted for 30 percent of Japan’s oyster production before the 2011 tsunami, but the volume in 2012 was a mere tenth of the pre-tsunami level as harvests were from the few rafts that had survived. Efforts in the following years were focused on replacing the floating rafts from which the oysters are suspended on lines and the anchors which keep them in place, and on rebuilding facilities for processing oyster spat. In September of 2013, reconstruction of rafts and seed oyster facilities in many areas was over 90 percent complete, though much equipment, such as vessels, was still shared among producers. In this year, many localities in Iwate and Miyagi are reporting that all rafts have been replaced (or even increased from pre-tsunami levels) and that their production has recovered.
Shipping started in October in Iwate and Miyagi prefectures, about a week later than usual. The quantity produced in the tsunami-hit area is up 20 to 30 percent from 2013, and is of good quality. Oysters are selling cheaply this year due to good supply. The wholesale price of oyster meats at Tokyo’s Tsukiji market is about 1,800 yen (USD 16.79, EUR 13.27) per kilogram — 20 percent below that of a year ago. Retail prices are at 400 to 600 yen per 100g.
In Fukushima, the prefectural government has been testing levels of radioactive cesium and strontium in marine products in its waters since April 2011. It measures weekly radiation levels of 150 fish samples from 40 locations, excluding a 5km radius of the nuclear power plant.
To reassure consumers, Japan has set a low radiation limit of just 100 becquerels per kilogram. In comparison, the U.S. level is 1,200 becquerels per kilogram. In the last year, only about 2 percent of samples have exceeded the limit, as opposed to over 50 percent in the months following the disaster.
Fish landings totaled 104,485 metric tons (MT) in Fukushima in 2010, before the quake, placing the prefecture at 18th among Japan’s prefectures, but all commercial fishing was banned in April 2011. Considering the subsiding radiation levels, 16 target products were recently approved for trial commercial fishing operations. Most of these products showed levels even below the lower detection limit of 16 becquerels per kilogram.
Levels have been particularly low among invertebrates like oysters, squid and octopus. The highest levels have been among bottom-feeding fish, such as sand-lance, cod and flounder. These may occasionally feed at a hotspot of accumulated radioactive sediment. Flatfish such as slime sole were previously a lucrative local product, as the prefecture’s proximity to Tokyo allowed fresh shipping.
Test commercial fishing commenced on 25 September this year when 21 trawlers from the Soma Futaba Fisheries Cooperative Association in the prefecture hauled in 5 MT of seafood, including octopus and squid. Most of the catch was not among the approved target species and was thrown over. Target species confirmed safe for consumption in the sampling inspection were shipped to market. Two other cooperatives, from Iwaki and Onahama ports, started test fishing on 3 October.
Octopus appears to be the most readily accepted Fukushima seafood product so far, because of its very low radiation levels and because octopus prices are currently high on low Mauritanian supply. Ten 5-kilogram cases of boiled octopus were sold at the Tsukiji market following the test fishing. A document certifying that no radioactive material was detected was affixed to the cases.
Fukushima boiled octopus was also sold in a supermarket in Tokyo. Many of the customers expressed a desire to support disaster reconstruction. However, restaurant demand appears to be stronger than retail, as some consumers remain leery of all foods from the area.
