Why Are There No Snakes on the Island of Newfoundland?

The Labrador Current is that cold, rich, enormous flow of seawater down from Arctic Canada, along the coast of Labrador and then around the coast of Newfoundland. When I say "enormous", I’m talking about four million cubic metres per second on average. That’s the equivalent of about twenty Amazon Rivers (the world’s largest river) or two hundred and thirty-five Mississippi Rivers. Something that big is bound to have some sway.

Consider this: the climate on the west side of the North Atlantic is vastly different from the much warmer eastern side, thanks to the contrasting influences of the Gulf stream (warm) and the Labrador Current (cold). For example, Labrador is mostly south of sixty degrees latitude while Norway is mostly north of it, yet the coast of Norway stays largely ice-free, while Labrador is iced-in each winter.

It might be cold, but the Labrador Current is an abundant provider. Thanks to its richness, Newfoundland once had one of the world’s largest fisheries: northern cod, a fishery that fed much of Europe, the Caribbean, and beyond for five hundred years. Eventually it crashed for multiple reasons and has still not recovered fully. Perhaps it never will.

So it was that the Labrador Current that drew fishers from England, Ireland, Spain, Portugal, and Basque Country to harvest those super-abundant schools of cod, all part of a vast, international enterprise. Some of the fish merchants and many of the fishers eventually stayed and became the first settlers. For example, not far from where I live is the town of Cupids, first settled in 1610! So, the first peopling of what is now Canada began, in part, because of the Labrador Current.

Thanks to the Labrador Current, millions upon millions of little silver fish known as capelin come to the coastal waters of Newfoundland each year to feed on the early plankton bloom and spawn on the beaches. In turn, the capelin provide food for codfish, seabirds, whales, seals, and people. Sitting near the base of the North Atlantic food web, the little capelin is one of the most important fish in the North Atlantic.

About forty million seabirds come to the shores of Newfoundland each year in more than three hundred raucous colonies. These birds generally overwinter at sea, but they cannot lay an egg on the ocean, so it is to the remote cliffs and islands around Newfoundland that they are drawn by the richness of the Labrador Current. During early European settlement, the seabirds were to Canada’s east coast, what the buffalo were to the western plains: vital protein.

Along with the seabirds come the great whales. Some, like the humpbacks, have wintered in the warm waters of the Caribbean where the mothers bear their calves. But to feed the hungry youngsters, they move north to feed in the waters of the Labrador Current.

Each spring, pack ice or Arctic ice, which is the frozen seawater that covers the northernmost seas, slides south on the Labrador Current cloaking the northeast coast of Newfoundland. On this vast raft of ice, harp, bearded, and hooded seals whelp and nurse their young, while polar bears, drawn by the seals, stalk southwards reaching their southern extent somewhere along the northeastern coast of Newfoundland.

Mixed with the pack ice, or following behind, come the giant icebergs, most of which calved from glaciers in Greenland before drifting into the waters of the Canadian Arctic and then floating along on the Labrador Current (also known as “Iceberg Alley”). Some are so big they scrape the ocean’s bottom, creating furrows that look like a field ploughed by a drunken farmer.

The effect of the Labrador Current is so assertive that it even shapes Newfoundland’s cool climate, as compared to similar latitudes in mainland Canada. Climate, in turn, has a pervasive influence on the growth, abundance, and distribution of plants and animals. So, all in all, the Labrador Current fundamentally defines the nature of Newfoundland.

Let’s compare what happened on continental North America with glacial events on the island of Newfoundland. As the ice advanced from the north, most flora and fauna on the continent of North America could slowly adjust to the changing climate and migrate south. But on the island of Newfoundland, there was nowhere for it to go—all life was wiped out.

Then as the glaciers melted, retreating north, flora and fauna on the continent could move north again. But here, all that was left were the mountain tops and glacial rubble. It would take a long time for plants and animals to reach it again.

As time passed, windblown spores and seeds landed and found sustenance on the gravel and between the cracks of rocks. Mosses and lichens took hold and soil began to form. Eventually, seed-bearing plants found purchase and new ecosystems began to develop.

But for any land animal to arrive, it had to cross a large body of cold saltwater or, in winter, traverse an ice bridge between Newfoundland and the continent. Many animals—snakes, for example—could not do this, nor could any other cold-blooded reptile or amphibian.

As for freshwater fish, the diversity on the mainland is much greater than in Newfoundland. Bass, pike, catfish, sunfish, and many others are absent on the island because the saltwater between mainland Canada and Newfoundland is a toxic barrier to them. The predominant fish in the freshwater of Newfoundland are trout and salmon, both of which can tolerate saltwater to a lesser or greater degree.

As far as land mammals go, the black bear, beaver, muskrat, Arctic hare, lynx, red fox, ermine, otter, caribou, wolf, and pine marten all arrived on their own, as did the diminutive meadow vole, the only indigenous small rodent.

Meanwhile, just fifteen kilometres away across the Strait of Belle Isle, Labrador has nine species of mouse-like creatures. How the little vole got to the island, we can only speculate, but chances are it rafted over on a chunk of land that eroded away from a riverbank somewhere in eastern Canada.

Furthermore, Newfoundland has no racoons, porcupines, skunks, woodchucks, or ground squirrels. Quite a few mammals have been introduced—namely moose, mink, red squirrel, chipmunk, snowshoe hare, red-backed vole, and masked shrew. Newfoundland has been very lucky with these introductions, since none have caused an ecological disaster, but, with each one, there was that potential.

Moose are an interesting case study in the history of Newfoundland introductions. Four animals were imported and released in 1904. The population eventually grew to something over 100,000, all from that tiny gene pool. Without the wolf, the predominant predator of moose on the mainland, moose populations in Newfoundland must be managed through an annual hunt, to the extent that well-controlled hunts even occur in National Parks. Without them, too much habitat damage results from moose over-browsing.

Although the wolf was native to Newfoundland, it is thought to have been exterminated by 1930. Its cousin, the coyote, who is now widespread on the island, was a recent, natural immigrant who probably arrived on a windblown raft of ice after hunting for seals in the Gulf of Saint Lawrence. Oddly, in 2012 an animal whose DNA proved to be a wolf was shot on the Bonavista Peninsula. Who knows? Maybe they are making a comeback!

So, when you visit Newfoundland, you don’t have to worry about stepping on a snake in the bushes, nor about ticks or chiggers or many other nuisances. Bear in mind the simplifying effect of the last glaciation and that all life in Newfoundland is less than 12,000 years old—which, in the big picture, is pretty young.

If your visit is in the summer, you can escape the cooker that befalls the middle of the continent and feel the cool embrace of a climate largely defined by the refreshing Labrador Current. In the spring, icebergs, seabirds, and whales abound, while fall brings the cleanest air and the most beautiful light you will ever see. And Saint Patrick had nothing to do with any of it.