Exotic Species

OTSU, Japan — As exotic fish species from Europe, Asia and the Middle East make headlines in the United States, just the opposite is occurring in those same foreign countries involving America's most popular gamefish species.

Nowhere is this more apparent than in Japan, where the imported largemouth bass is threatening many of that country's native fish species.

In response to that threat, the Otsu District Court has upheld a Shiga prefectural ordinance that prohibits anglers from releasing bass after they have been caught. In other words, every bass caught must be killed.

Since that ban was first implemented in 2003, at least seven other prefectures have followed suit.

The controversy over how to manage non-native bass in Japan has been focused here because of Lake Biwa, the country's largest lake which now supports Japan's best bass fishing.

Since 1985, resource officials have tried — and largely failed — to reduce bass and bluegill numbers with gill nets. Soon they will target fingerlings with nets.

Meanwhile, bass anglers and other critics of the ban on catch and release insist that pollution and shoreline development have contributed considerably to the loss of native species, which are an important part of traditional Japanese cuisine. Bass fishermen in Japan plan to appeal the ruling to a higher court.

Elsewhere, some prefectures recognize that bass fishing is an economic asset, and they allow local fishermen's associations to levy fees from anglers who want to fish for this invader from the United States. But they also ban the release of bass in waters where they do not already exist, entrusting the associations to help with enforcement.