New research paper shows wolf predation on wild horses


Zoocheck Note: For many years, a myth has been perpetuated by persons, businesses and others who oppose wild horses living on Canadian landscapes that wild horses have few predators. It was known that bears and cougars predate on wild horses and this paper now shows that wolves can be major predators of wild horses as well. Zoocheck is pleased to have funded its publication. Read the article at Canadian Field Naturalist.

 

Wild horses are an important component of the diet of wolves in the BC Chilcotin


Writing: Sadie Parr and Wayne P. McCrory, RPBio.
Photos: Sadie Parr

Studies in various parts of the world have shown that where horses roam freely, they are a dietary item for large carnivores that still survive in those ecosystems. Wolves are flexible and opportunistic predators adapted to feeding on a variety of diverse species including wild horses where they coexist.

I was fortunate to carry out a wolf diet study from 2013 to 2017 in the Tŝilhqot’in Xeni Gwet’in First Nation ?Elegasi Qayus Wild Horse Preserve, located in British Columbia’s Chilcotin region. The study involved a partnership with the Xeni Gwet’in community of the Tsilqhot’in First Nation, Valhalla Wilderness Society, Friends of Nemaiah Valley, and Wolf Awareness. I was able to collect and analyze 122 wolf scats that provided key data on the feeding habits of wolves in this unique ecosystem.

The study was focused in an area which is often referred to as the Brittany Triangle, traditionally named Tachelach’ed by the Tsilqhot’in Nation. This area includes one of Canada’s few remaining wild horse (Equus ferus caballus) ecosystems, the others being Nova Scotia’s Sable Island in the Atlantic, a population in the foothills of Alberta’s Rocky Mountains, and a small population of wild ponies in Saskatchewan’s Bronson Forest. Smaller herds of free-roaming horses are stewarded by some Indigenous nations in BC, Alberta and Saskatchewan.

Wild horses have roamed the land in Tachelach’ed for more than 300 years. They are an essential part of this unique ecosystem and of Xeni Gwet’in culture. The horses live a survival-oriented lifestyle through harsh Chilcotin winters and among a carnivore guild which includes wolves, grizzly bears, black bears, cougars, wolverines, lynx, and coyotes.

In some western US states, horse populations can grow quickly in areas where most or all of the large carnivores have been extirpated. Population control methods underway in these areas often involve controversial methods such as translocation, immuno-contraception, round-ups, and aerial shooting programs which can incur high financial and animal welfare costs.

Where natural predation of horses is known to occur in North America, few studies have been conducted. Most of the studies that have taken place involve mountain lions in the United States, where it was determined that horse population growth along the central California-Nevada border was limited in a top-down manner by the spring predation of mountain lions.

WHAT WE LEARNED

Although the sample size of scats collected and analyzed is considered small at 122, nevertheless scat analysis determined that the wolves I was studying consumed wild horses throughout the year. They also ate a variety of other species, including deer, moose, small mammals such as mice, voles, and rabbits, and a small amount of beaver, domestic cow, and fish. However, wild horses were the most common food item. Salmon runs in the area were not utilized.

It is important to note that one of the limitations of scat studies is that they cannot determine how an animal died (ie. predation vs. scavenging). Further study is required to determine if wolves are hunting horses and/or contributing to top-down regulation of the wild horse population.

Of important note, aerial surveys and ground observations conducted over the previous five years indicate that the wild horse population in the core study area appears stable. This was confirmed by a comprehensive BC government-Tsilhqot’in wild horse survey that concluded numbers had remained the same for some time. The west Chilcotin has 2,800 wild horses.

My study is being presented to the Tsilhqot’in and BC governments in hopes of providing important baseline scientific information for a holistic and ecosystem-based approach to the conservation and management of wild horse and wolf populations.

With much thanks to Zoocheck, the publication of this research in a scientific journal was made possible. Read the article in the Canadian Field-Naturalist Canadian Field Naturalist.