Non-native monkeys get a raw deal on isolated island

Back in the 1960s, someone had the bright idea of introducing non-native monkeys to a barren, uninhabited outcrop off the Izu Peninsula south of Tokyo as a tourist draw.

Before long, a local boat charter company realized it could drum up business by offering cruises that allowed visitors to feed the monkeys, which by then were starving.

Decades later, the central government designated Formosan rock macaques as an invasive species.

For the few remaining monkeys on Onejima island, a bleak spot that lies roughly 50 meters from the southern extremity of the Izu Peninsula in Shizuoka Prefecture, the edict amounted to a death sentence, and a horrible one at that.

For starters, permission from the environment minister is needed to feed the animals. For all practical purposes, they were left to fend for themselves.

So, after more than half a century on the island, the monkeys are to be killed. The only bright spot in this story is that the animals will be put to death painlessly by injection.

It is also a stark lesson in skewed decisions over the years to introduce non-native species to Japan, only to be later designated as "invasive species," captured and exterminated.

Onejima, which lies at the southern tip of the Izu Peninsula, comes under the jurisdiction of Minami-izu, a town in Shizuoka Prefecture.

Izu Cruise, based down the coast in historic Shimoda, operates sightseeing trips around the island. The boat seats up to 80 passengers and the adult fare is 1,200 yen ($15).

On a recent trip, five or so monkeys scampered onto rocks along the shore as the boat approached.

The skipper, who has taken it upon himself to feed the troop, tossed over scraps of sweet potato, which were quickly devoured.

As the boat departed, the monkeys dashed along the shoreline as if to make chase.

Onejima's coastline barely stretches 1 kilometer. It lies within Fuji-Hakone-Izu National Park.

A local tour operator released Formosan rock macaques on the island in the 1960s to draw tourists.

Many years later, the central government invoked the invasive alien species law of 2005 to prevent the monkeys from breeding with Japanese macaques and damaging crops. Since then, official permission has been needed to feed the monkeys.

Onejima is strewn with rocks, and there is nothing to eat.

A local tour operator, and later Izu Cruise, which took over the sightseeing boat business in 2007, made a point of feeding the monkeys and thumbing their noses at the authorities. Passengers were encouraged to purchase 100-yen bags of sweet potato to feed the monkeys.

But ever since the Environment Ministry instructed Izu Cruise to improve its compliance with the law, tour members have also been prohibited from feeding the monkeys. Now only the captain does so, to keep the famished monkeys from escaping the island. Less than 10 remain.

A staff member of Izu Cruise explained: "The monkeys' numbers have been declining even though we've been feeding them without permission. We wanted to wait for them to die out naturally. We also considered transferring them to another facility, but in the end we decided to give them lethal injections since a sudden change of environment would be harsh for them."

The company has informed the Environment Ministry that it will destroy all the monkeys by July.

The situation on Onejima is by no means without precedent.

In the late 1970s, a popular television cartoon called "Araiguma Rascal" (Rascal the raccoon) triggered a surge of interest in the mammal, which is native to North America.

Raccoons were imported as pets, but owners tended to abandon them when the animals were no longer cuddly and had turned aggressive.

Raccoons became so common in the wild that experts feared that local ecosystems would be destroyed. So raccoons, along with the Formosan rock macaques and other species, were designated as invasive species in 2005.

Raccoons are blamed for causing 280 million yen in crop damage across Japan in fiscal 2009. They are natural predators of salamanders and other rare native species.

A raccoon was even captured in the Fukiage Imperial Gardens inside the Imperial Palace in central Tokyo.

To date, 105 species of plants and animals, including fish and insects, have been designated as invasive species.

There have also been cases of coypus--a South American mammal--and snapping turtles turning up in urban areas.

From the 1930s through the 1950s, there were numerous instances of Formosan rock macaques and Formosan squirrels escaping from Oshima (one of the Izu Islands) and a zoo in the city of Wakayama. Once in the wild, the animals multiplied.

The Tokyo metropolitan government, which has jurisdiction over a number of far-flung islands, is determined to eradicate the creatures.

Yukihisa Mito, assistant director of Nihonzaru (Japanese macaque) Field Station, an NPO based in Mutsu, Aomori Prefecture, says, "The cause of the designated invasive species problem is the irresponsibility of owners. Only the animals get hurt. We wish people would be realistic and think carefully before deciding to keep an imported animal as a pet."