The Environment Ministry on Tuesday declared the eradication of nonnative mongooses on Amami-Oshima island, a UNESCO World Natural Heritage site in Kagoshima Prefecture.
The declaration was based on judgment by a group of experts on scientific grounds, taking into account that the capture of mongooses has not been confirmed for more than six years since the last one was caught in April 2018.
According to the ministry, this is one of the world’s largest-scale cases in which long-settled non-native mongooses have been eradicated.
Around 30 small Indian mongooses, which mainly live in South Asia, were originally brought into Amami-Oshima in 1979 with the aim of getting rid of poisonous habu snakes and rats on the island.
The number of mongooses on the island grew quickly and their estimated number peaked at some 10,000 around 2000.
However, their effectiveness in eliminating habu vipers could hardly be confirmed. Instead, they were found to be preying on the island’s endemic Amami rabbits and other native species.
The ministry therefore began full-fledged efforts to reduce the mongoose population in Amami-Oshima in 2000 and has since captured some 32,000 mongooses.
Following the eradication declaration, the ministry will remove traps that have been set on the island, but will continue monitoring by cameras to prevent a new group of mongooses from entering the island.
The ministry plans to utilize its expertise acquired through the Amami-Oshima case to eliminate mongooses or other non-native species in the country. For example, the ministry plans to send personnel belonging to a team of mongoose-capturing experts to the northern part of the main island of Okinawa Prefecture, where the settlement of mongooses has been confirmed.