A moreish proposal: Japan’s plan to control invasive species by turning them into food

  • Snapping turtles, black bass and American crayfish are just some of the unwanted intruders getting the culinary treatment
  • Yet chefs might have a harder time creating palatable dishes out of other non-native species such as fire ants, raccoons and anole lizards
PUBLISHED : Tuesday, 13 November, 2018, 12:00pm
UPDATED : Tuesday, 13 November, 2018, 10:31pm

Tired of fighting what seems to be a never-ending battle against non-native species of animals that are decimating local flora and fauna, a number of communities across Japan have come up with a simple solution: eat the invaders.

The prefectural government of Chiba, to the east of Tokyo, has been struggling for decades to contain a booming population of snapping turtles that have taken up residence in the marshes and paddies surrounding Lake Inba-numa.

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Most of these turtles, which are not native to Japan, started out being bought as pets. When they became too big – an adult snapping turtle can weight up to 10kg, which is far from ideal for a small Japanese flat – their owners decided to release them into the wild instead of having them put down.

The result has been the creation of a breeding population of the turtles in northern Chiba, with the prefecture estimating that there are now 16,000 of the creatures in and around the lake.

The prefecture recently organised a weekend event during which dozens of captured turtles were turned into soup, boiled with garlic and ginger, and shared with the local community. Snapping turtle might not be a recognised delicacy in Chiba, but locals said it had the taste and texture of plump chicken.

To me this seems like a sensible use of local resources
Kevin Short, environmental professor at the Tokyo University of Information Sciences

“To me this seems like a sensible use of local resources because the numbers of these turtles has really risen in recent years,” said Kevin Short, a professor who specialises in environmental education at the Tokyo University of Information Sciences and a resident of Chiba Prefecture.

“But the local authorities need to make a decision on whether they are going to try to eliminate the turtles in the lake entirely, which is the policy they have had previously, or if they are now going to simply manage the population through this sort of culling.”

“They may very well have reached the conclusion that they can’t eradicate the turtles – there are just too many of them and they breed every year – so controlling their numbers through this sort of event is the next best thing,” he said, pointing out that other local authorities are trying similar tactics with other non-native species that were introduced to Japan in decades gone by.

A restaurant on the banks of Lake Biwa, in Shiga Prefecture in central Japan, serves locally caught black bass, which were originally imported to stock lakes for recreational fishing in the 1920s, but swiftly adapted to their new environment and displaced native species of freshwater fish.

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Similarly, a fisheries cooperative in Hokkaido is capturing and selling crates of crayfish whose predecessors were introduced from the Columbia River in the United States in the 1920s. The crayfish were meant to be food for yet another transplanted creature, the American bullfrog, which Japanese farmers raised in the pre-war years for frogs’ legs that were frozen and shipped to France.

Inevitably, both the frogs and the crayfish made successful bids for freedom, said Short, and have since thrived.

“The problem with the crayfish is exponentially different from that of the turtles or black bass because they have naturalised over a far larger area and made themselves at home in any sort of watery habitat,” he said. “There must be billions of them here by now.

“They’re certainly edible, it’s just that someone out there has to encourage Japanese people to develop a taste for them so that they can be harvested on a large scale.”

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Not all of Japan’s problems with invasive species can be solved so easily through the culinary arts, Short adds, pointing out that the country is also struggling to control burgeoning populations of fire ants, raccoons and the green anole lizard.