Sable Island, a 42-kilometre long sliver of sand formed 10,000 years ago by the workings of glaciers, is home to about 500 horses. Paul Gierszewski photo (CC BY-SA 4.0)

The remotest island in all of Canada is a 42-kilometre long sliver of sand gracing our continental shelf, formed 10,000 years ago by the workings of glaciers.

We call her Sable.

To this day, its shores support the largest breeding colony of grey seals on earth alongside several endemic species like the Ipswich sparrow and Sable Island sweat bee, unique to the windswept barrens this island has to offer. But Ian Jones, a professor of biology with Memorial University specializing in seabirds and island conservation, said it used to support much more, such as a lush array of lower vegetation that safeguarded soil and fresh water, making this a seabird paradise in days long gone.

I’ve heard several different versions of this story, but the most objective account seems to come from Tony Lock, a now retired researcher with the Canadian Wildlife Service. He writes that, in the 1700s, a Bostonian man by the name of Andrew Le Mercier brought to the shores of Sable cattle, sheep, hogs, and horses in hopes they would populate the island and make themselves available for the occasional harvest. Sable slowly rid itself of these invaders, however, until only one species of mammal remained, those feral beasts we call Sable Island Horses.

These short, hardy, English draft horses survived on the local grasses, learned to dig themselves wells for the island’s scarce fresh water, and while harsh winters routinely trim their numbers, they have persevered for centuries, today numbering around 500 strong. At times they’ve been put to work in short-lived island settlements, and individuals have been culled, taken away, or added to this population for a variety of reasons, but mostly they’ve been on their own.

The invasion of these horses was not a harmless one, however, as few such introductions are. In the 1950s, biologists called attention to changes these animals wrought on the island’s ecosystem, such as the overgrazing of its plant life and the compression of its soil, contributing to Sable’s ongoing desertification. As well, they pose a threat to wildlife through trampling.

While they’ve adapted admirably to an environment they clearly weren’t meant for, their lives are anything but ideal. The lack of shelter during winter causes the aforementioned die-offs – as many as 200 at a time – but so does the lack of fresh water and the side effects of island grazing. With each mouthful of greens, these horses also take in sand that their teeth did not evolve to handle, eventually wearing them down. This dooms them to extreme discomfort, conditions they wouldn’t be subjected to on the mainland. As well, they have a small gene pool, the consequences of inbreeding a considerable threat to their survival in the long term. Their lifespan is a mere 4-5 years.

After failed attempts at preventing these winter losses with aerial hay drops, our government made plans to remove the horses from Sable, but a public outcry to then Prime Minister John Diefenbaker led to his noteworthy amendment of the Canada Shipping Act, protecting these horses from interference of any kind and cementing their place on Sable Island.

Circumstances changed somewhat in 2013 when Sable Island was declared a National Park, now under the jurisdiction of Parks Canada, which has the firm mandate of removing invasive species from its protected lands. But, of course, that hasn’t happened, the public relations nightmare of a half century ago firmly on their minds, I suspect, and not the best interests of the ecosystem itself.

Sable was once an isle of consequence for the seabirds of Atlantic Canada, said Jones, but its ongoing degradation at the hooves of suffering horses has left it wanting. He was among those who praised its designation as a national park, knowing this should have meant progress, but alas.

“Instead of having a national park protecting unique biodiversity on Canada’s most remote island, we have a pony farm for tourists, basically,” said Jones. He points to the Ipswich sparrow in particular, unique to this island and dependent on its disappearing savannah.

“Once things are extinct, they’re gone forever,” he said.

I’ve been ensnared by the romanticism of Sable Island’s horses as much as anyone, taken with their endurance, struggle, and beauty, and were such a trip possible I’d happily see them firsthand, but then there’s the suffering of the horses, of sable, and of the myriad species and ecosystems this unnatural blend of life is putting at risk. We, as a province and a country, have twisted ourselves into a knot keeping these horses on an inhospitable sandbar, but I think it would be a worthy and moral enterprise bringing them home, to the Nova Scotian pastures of their forebears, where awaits medical care, eager owners, and the adoration of a nation.

Zack Metcalfe is a freelance journalist, columnist and author active across the Maritimes.