Did Saint Patrick Drive the Snakes Out of Ireland?

The short answer is that no, there are no snakes in Ireland. In fact, it’s rare for an island to have no wild snakes, and so Ireland is conspicuous for being one of them. Given that, it’s no surprise that so many tourists and travellers want to know what happened to the slithering creatures . 

In the article, we’ll be taking a closer look at the two main answers to the question of what happened to the snakes: the scientific (an ice age) and the legendary (Saint Patrick). This answer might sound plausible, but there’s something about the iconic figurehead of St. Patrick’s Day which makes the legendary take seem just as believable. 

And so with that in mind, let’s go over the main theories behind what happened to the snakes of Ireland so that you can make your own mind up.

Does Ireland Have Snakes?

The simple answer to this is that no, there are no snakes in Ireland. In fact, while there are over 3,400 recorded species of slithering creatures throughout the world, not one of them has ever been recorded in the wild in Ireland.

Of course, just because there are no wild snakes, it doesn’t mean that there are no snakes at all. There are plenty of serpents in zoos and in private collections, but that’s very different to them being native to the land. We can safely bet that a decent number of snakes have escaped or been released into the wild over the years, but they’ve failed to breed and to colonise the land. 

In comparison, nearby Great Britain has three native snake species: the grass snake, the smooth snake and the adder, the latter of which is the country’s only venomous snake (although bites from it are rare). 

Ireland and Great Britain are only 12 miles (19 kilometres) apart at their closest point, and you can see across the North Channel from Northern Ireland to Scotland on a clear day. And yet despite that seemingly insignificant distance, one has snakes and the other doesn’t. But why is that?

Why Ireland Doesn’t Have Snakes

The Scientific Answer: An Ice Age

If you ask a scientist, “Why are there no snakes in Ireland?”, they’ll give you the boring (but true) answer that it’s all because of an ice age.

According to researchers, during the last Ice Age (which took place around 10,000 years ago), Ireland was completely covered by glaciers. It was a difficult time for life to survive, and it was particularly difficult for cold-bloodedreptiles. These creatures (known as ectotherms) need external heat to regulate their body temperature, and that kind of heat just wasn’t available.

As time went on, the glaciers melted and the climate warmed back up again. There were still snakes further south, but Ireland became separated from the European mainland by the Irish Sea before they were able to move back up north. Great Britain remained connected to Europe for 2,000 more years, which was plenty of time for snakes to complete their migration.

Scientific research backs this all up, with palaeontologists confirming that no fossilised serpents вhave been found in Ireland. There’s plenty of them across the sea in Great Britain, but we don’t need fossils to know what happened there. We can compare the existing species in Britain with those in Europe.

The Legendary Answer: Saint Patrick

If you want the more poetic answer to the question of “why is there no snakes in Ireland?”, this is it.

It all goes back to Saint Patrick, the patron saint of the Emerald Isle and the reason why St. Patrick’s Day is celebrated each year on March 17th (his birthday). According to the legend, Saint Patrick drove all of the snakes off the island during a 40-day fast and prayer on Croagh Patrick mountain. The mountain, which is over 750 metres tall, attracts as many as 30,000 pilgrims every year.

Interestingly, the full legend goes that the snakes attacked Saint Patrick and he simply ordered them to leave, which they quickly did by throwing themselves into the sea. This can be interpreted either as a recollection of what happened, or as a symbolic tale of paganism, with the snakes representing the druids who were displaced by the rise of Christianity. 

This myth should be treated like all myths: as a cultural explanation as opposed to a scientific fact. It makes for a good story, but that’s likely all it is. 

What Experts Say

Now that we’ve got an answer to the question of “are there any snakes in Ireland?”, it’s time for the definitive answer to why there are none to be found on the Emerald Isle.

Experts are unanimous, from palaeontologists to zoologists and other scientists. The absence of snakes in the country is explained solely by the cold climate during the ice age and its effects on the ecosystem, along with the ensuing geographic isolation. The Saint Patrick story is just that: a story.

One of the most interesting things of all is the fact that there’s nothing about Ireland’s modern climate that makes it unsuitable for snakes. For example, the grass snake could flourish, at least theoretically. However, it would be a mistake to deliberately introduce snakes to the country, because the local wildlife has no evolutionary defence mechanisms against them.

Collie Ennis of Trinity’s School of Natural Sciences put it best when he said, “Native animals that would not have evolved around snakes as predators would be lost if snakes were introduced here, but snakes could probably persist.”

Are There Any Snakes in Ireland at All?

Let’s come back round full circle to that question of “is there snakes in Ireland?” After all, to say that there are no snakes in Ireland wouldn’t technically be true.

The fact is that the wild population of snakes comes to a grand total of zero, but the overall snake population could stretch into the tens of thousands. Most of these are in zoos and terrariums, with one of the most notable being Dublin Zoo.

With that said, there have also been isolated cases of exotic snakes that have been found after being illegally imported or escaping captivity, but that doesn’t constitute a wild population and they don’t go on to breed.

So yes, there are snakes in Ireland. They just don’t live out in the wild.

Where Else Are There No Snakes? 

Believe it or not, the snake Ireland story isn’t the only time we’ve seen something like this happen. There are several other places that also have no snakes or reptiles, but for different reasons.

New Zealand, Iceland and Antarctica also have no native species. Here’s why:

• Iceland is too cold for the majority of the year
• Antarctica is even colder, providing extreme conditions that are incompatible with most forms of life
• New Zealand could support snakes, but it was isolated before snakes were able to reach it. 

That makes Ireland unique in that it’s the only one where snakes could theoretically live; they just don’t. They never made it back after the Ice Age.

And Saint Patrick never had to banish them from the country because they were never there in the first place.