Could Ireland’s ecosystems cope if we introduced St. Patrick’s scaly foes?

But what would happen if St. Patrick's scaly foes were introduced now? Would Ireland's native wildlife sink or swim?

Experts from Trinity College Dublin believe snakes could certainly slither into Ireland's ecosystems if introduced but would likely cause trouble for native ecosystems. There are enough troublesome pests in Ireland today, such as the introduced New Zealand flatworm, which people would like to send on its merry way with some modern-day St. Patrick-style sorcery.

Associate researcher in Trinity's School of Natural Sciences, Collie Ennis, is a snake expert. He said: "If you look across the water, the UK has very similar environmental conditions to ours and snakes fit right in. Native animals that would not have evolved around snakes as predators would be lost if snakes were introduced here but snakes could probably persist."

Interestingly, a number of attempts have been made to introduce grass snakes, one of three species that are native to Britain, over the past 100 years. Until recently, grass snakes could even be bought in pet shops throughout the land.

Collie Ennis added: "There are anecdotal records of individuals releasing several grass snakes along the Royal Canal in Dublin but luckily the snakes failed to establish populations. This could simply be due to the small numbers of snakes introduced, the unappealing climate, or to a combination of these factors."

Worryingly, Professor of Zoology at Trinity, Yvonne Buckley, says there are lots of other invasive species that have established, and whose ecological influence is growing quickly. Some of these species present a real threat to Ireland's environment and economy.

Near the top of that list is the New Zealand flatworm, a relative newcomer to Ireland's shores, which feeds on native earthworms that provide important ecosystem services as well as currying favor with farmers for enhancing the fertility and drainage of agricultural soils.

Professor Buckley said: "New Zealand flatworms are not snakes but they are long and legless, and our ecosystems and farms would benefit from their removal. It certainly would be legendary if I could magically banish these legless interlopers! Unfortunately it costs a lot more to banish unwanted pests now than it did in St Patrick's day, so introduction of snakes would be a very expensive mistake."

Other invasive species that threaten Irish biodiversity and harm the economy include zebra mussels, muntjac deer, harlequin ladybirds, mink, mitten crabs, rhododendron and Japanese knotweed.