TOKYO, Oct. 15 – The number of wild boars caught in the Tohoku region in northeastern Japan has been increasing sharply as their areas of habitat expanded north.
A total of 43,885 were captured in the six prefectures in Tohoku – Akita, Aomori, Iwate, Fukushima, Miyagi and Yamagata – in fiscal 2019, more than doubling in five years.
While it has been considered difficult for wild boars to pass the winter in the region, the increase in the captures can be attributed to global warming and a growing population of the animal.
The prefectures are on the alert, as wild boars not only cause damage to crops but also could become a source of classical swine fever infections.
The number of wild boars caught in the six prefectures was 20,701 in fiscal 2015, which means the cases rose by more than 23,000 in five years.
Since it is difficult for them to find plants to eat in winter in areas where snow accumulation of 30 centimeters or more continues for 70 days or more, it had been believed that they could not survive north of Miyagi.
However, in fiscal 2019, three wild boars were captured in Aomori, the northernmost prefecture in Honshu, Japan’s main island. Witness reports of wild boars started to increase in the prefecture since fiscal 2017, according to the Aomori Prefectural Government.
Captures are rising since fiscal 2016 in Akita, with five caught in fiscal 2019.
In Yamagata, the number of wild boars caught totaled 2,002 in fiscal 2019, rising 8.7 times from fiscal 2015. The number was 346 in Iwate, up 8.6 times from fiscal 2015.
According to the agriculture ministry, the amount of crop damage caused by wild boars in the six prefectures reached 271.56 million yen in fiscal 2018, topping 200 million yen for three years in a row.
The prefectures are also facing an urgent task of preventing domestic pigs from getting infected with swine fever.
After a wild boar infected with swine fever was found in Fukushima in September, vaccination of pigs started at farms in Fukushima and neighboring Yamagata and Miyagi.
Although Iwate and Akita are not included in the area where vaccinations of pigs are encouraged, the two prefectures’ governments are alarming pig farms and urging them to follow hygiene management standards more strictly, such as sanitizing, to avoid bringing in the disease.