The Environment Ministry completed Saturday the netting of fish in an imperial moat in central Tokyo and, contrary to a 2000 survey, found nearly 90 percent of the catch to be native fish, not marauding foreign species.

The operation, which began Feb. 27 at the Ushigafuchi moat of the Imperial Palace, was designed to protect the moat's native species from omnivorous nonnative fish, such as bluegill sunfish and black bass.

Of the 10,851 fish caught, 9,476 -- or 87 percent -- were "motsugo" or other native species. There were 1,375 nonnative fish, including 1,299 bluegill sunfish and 64 black bass, the ministry said.