Essay

Japanese invaders

By Mike Dwane

音声ダウンロード

The legend goes that Ireland has no snakes because St. Patrick, our patron saint, chased them all into the sea in the fifth century.

It’s a nice story to tell tourists but the scientific record shows Ireland, unlike the U.K., has had no snakes since the Ice Age. A country as cold as Ireland is not a welcome habitat for cold-blooded creatures and, in fact, we only have one native reptile, a small lizard that lives on bogs and mountainsides.

Imagine my surprise then when fisheries inspectors recently found a turtle in my local river. And not just any old turtle either but the yellow-bellied slider, which is native to Florida.

Recent sightings of warm water sharks and jellyfish off the Irish coast have been put down to global warming. But I’m afraid it can’t be said that our interloper turtle confused Ireland with the Sunshine State! He was most likely a fugitive pet or one turned loose in the wild by irresponsible owners.

Wildlife can often flourish in new countries to such an extent that these invasive species can become a major problem. Anybody who has tried to bring food into Australia and been unlucky enough to be interrogated by immigration officers in Sydney, for example, might find them paranoid about such matters. But it’s more understandable when you consider the damage done by invasive species to Australia’s unique ecosystems. There, introduced rabbits have destroyed crops and the poisonous cane toad has pushed other species to the brink of extinction.

In Ireland, our problems are less dramatic and the worst invasive species here are plants. One is the rhododendron, a shrub-like plant from Asia that can grow so thick as to be impenetrable. Last month, two hill-walkers had to be rescued after spending five hours trapped in a maze of rhododendron!

And I’m afraid that the plant that our government considers to be the biggest threat is the Japanese knotweed, or itadori. The roots of this invader grow so thick and hardy that they can damage buildings, and banks have been known to not approve mortgages if itadori is present on the property. I see the Japanese make tea from this plant but I can’t imagine anybody looking for a home loan explaining this to their bank manager.

A more welcome Japanese guest has been the variety of deer we know as the sika deer, or nihonjika. These were introduced by a nobleman on his estate in the 1860s but escaped. They spread around the country and are now the most common type of deer here. They can even be seen in the middle of Dublin, where the wild herds roaming the Phoenix Park have become a tourist attraction!

日本からの侵入者

アイルランドにはヘビが生息していない。それどころか、実はアイルランド原産の爬はちゅう虫類は、ある種のトカゲだけだ。それなのに最近、筆者の家の近所の川でフロリダ原産のカメが見つかったという。

The Japan Times ST: July 25, 2014