Approximately 160 kilometres off the east coast of Halifax exists Sable Island—a thin crescent of shifting sand, located at the edge of the Continental Shelf. Dubbed “The Graveyard of the Atlantic” (due to the more than 350 shipwrecks off its shores), the 32-km2 stretch of land is protected and managed by Parks Canada, with all visitors requiring advanced permission from the agency. Indeed, Sable Island is extremely isolated—save for a unique population.
Enter the Sable Island horse. Descendants of equines introduced to the island in the 1700s, this group of 500 feral horses is classified by Parks Canada as “a wild population of a naturalized species.” Specifically, the horses, which are protected under the Canada National Parks Act and the National Parks of Canada Wildlife Regulations, exist with minimal human intervention. They do not receive veterinary care and, importantly, people are not allowed to touch, feed, or interact with them.
This lack of intervention is precisely what attracted population ecologist Philip McLoughlin, BSc., PhD.
“I set out to establish a program aimed at filling a specific niche in ecology in Canada: the individual-based study of a wild vertebrate that lives free from predation, interspecific competition, and human interference (to allow me to focus on the role of intraspecific density-dependent phenomena in ecology and evolution),” he says. “After scouting several locations across Canada, I quickly realized that the horses of Sable Island presented an almost ideal system for the study of population ecology and evolution.”
Since 2007, Dr. McLoughlin, who is an associate professor at the University of Saskatchewan (USask), and his team of researchers at the McLoughlin Lab in Population Ecology have been tracking the “life histories and movements” of each horse on Sable Island with the hope of improving understanding of how individual dynamics can help inform population-level phenomena.
“Our program on island ecology also includes significant work on sea-to-land nutrient transfers and links between seals, seabirds, and horses through vegetation,” he says. “We maintain a program on the successional dynamics of the island and the role of the horse in this system.”
In the next issue of Veterinary Practice News Canada, we speak to the researcher to find out more about these feral horses and the ways in which his team’s findings could help advance equine veterinary science.
Check out the excerpt below.
“The horses live free and die free, so to speak,” Dr. McLoughlin tells Veterinary Practice News Canada. “Since the early 1960s, there has been, by regulation, no human interference allowed. This precludes things like feeding or provision of veterinary care. In fact, the horses are classed as ‘naturalized wildlife’ by Parks Canada Agency and are treated as such.
“Much like many national parks, policies are in place to maintain a distance between horses and tourists (for safety), including, for example, that tourists do not approach to within 20 metres of a horse. By its nature, research may require approaching wildlife to within closer distances—for example, as we sample DNA from known horses using swabs of dropped feces or to sample for parasite loads, which requires timely collection of samples (especially when sand is blowing about and presents a contamination risk to samples). However, all of our work is non-invasive in the sense that no horses are captured or handled; only watched and photographed. I have several projects where we capture wildlife to track animals (e.g. caribou, moose, wolves), but the horses do not need capture on Sable Island, as we can identify all of them from a detailed photographic database. Additionally, through our survey methods, we can obtain GPS locations of where animals stand once they move on (on their own).
“People, of course, have a special relationship with horses—a product of several thousand years of domestication. We are respectful of this relationship as much as we are respectful of the wild nature of this population, which has been free-ranging since the mid-1700s.”
To read the rest of our discussion with Dr. McLoughlin, be sure to check out the upcoming issue of Veterinary Practice News Canada!