The population of the Okinawa rail, a flightless bird native to northern Okinawa Prefecture, is recovering thanks to a campaign to capture an introduced predator — the Asian mongoose.
The Okinawa rail, known as "Yambaru Kuina" in its native northern Okinawa Island, drew national attention in 1981 when it was classified as a new species.
Now it's an endangered species due to the presence of the mongoose, a predator imported 100 years ago to reduce the population of venomous "habu" snakes.
While there were an estimated 1,800 birds in 1985, the number dropped to less than half that number before the central and prefectural governments launched a serious effort in fiscal 2000 to capture the mongooses using traps and dogs. The Okinawa rail population recovered to 1,500 in fiscal 2012.
But Ichihito Yamamoto, a wildlife conservation official from the Environment Ministry, warned the corner hasn't been turned yet.
"There should be no optimism and sustainable efforts are necessary," he said.
With a catch rate of about 200 mongooses per year, their number has declined to one-third of the peak. But the number will rise "if we ease up on our work now," Yamamoto said.
Stray dogs and cats, and even motor vehicles, take their toll on the bird too.