Photo/IllutrationWild boars in a snowy area in Yuzawa, southern Akita Prefecture, in March 2017 (Provided by the Yuzawa city government)

  • Photo/Illustraion

AKITA--Wild boars are damaging crops in the northern Tohoku region where the species was believed to be unable to survive winter, and their growing presence is being blamed on climate change.

In Akita Prefecture, the animal was first discovered in a southern city in 2012, and sightings have since been reported in northern areas, with the total number increasing.

While 42 boars were spotted in fiscal 2016, 35 had already been found this fiscal year by December.

The first damage to agricultural products was also reported in fiscal 2016. Boars damaged potatoes, rice and other crops on 11 occasions this fiscal year.

A 77-year-old woman in a mountainous area of Kita-Akita, a city in the northern part of the prefecture, said her potato field was damaged by a boar in May.

“I often find bears and raccoon dogs around here, but it was the first time that a wild boar has appeared,” she said. “As the animal got a taste of success, it may come back.”

According to the Akita prefectural government and other sources, it is believed that boars cannot survive the coldest months in areas where there is snowfall of 30 centimeters or more for 70 days or longer.

An official from the prefecture’s natural protection section said boars are moving up the Japanese archipelago “largely because global warming has reduced snowfall, making it easier for them to survive winter even in the Tohoku region.”

Prefectural authorities started a five-year plan this fiscal year to capture more boars by providing financial support for obtaining hunting licenses and purchasing guns.

But an official of neighboring Iwate Prefecture, where crop damage has increased, said dealing with boars is difficult.

“Although we set traps, boars are rarely captured,” the official said. “There are serious technical problems in addition to the advancing age and a shortage of hunters.”

According to the agriculture ministry and other sources, a total of 940,000 wild boars are estimated to inhabit Japan.

In fiscal 2015, boars caused 5.1 billion yen ($46.52 million) in damage to agricultural products, accounting for 36 percent of all damage by animals. The figure was the second largest, just behind deer’s 42 percent.

Of crop damage caused by boars, the largest amount, 1.5 billion yen, was reported in the Kyushu region in southern Japan. The Tohoku region is estimated to have suffered 200 million yen in damage.

Wild boars were previously thought to be able to live only in Miyagi Prefecture or farther south. The animals were not discovered in the four prefectures in the northern Tohoku region: Yamagata, Iwate, Akita and Aomori.

But crop damage by boars started to be reported in Yamagata and Iwate prefectures around 2010. In August, the boar was confirmed in Aomori, the northernmost prefecture on Japan's mainland, where the animal was believed to have disappeared more than 100 years ago.