WHOAS reining in wild horse numbers

Olds charity is using dart guns to administer a contraceptive 
vaccine that greatly reduces a mare’s chance of getting pregnant

The Wild Horses of Alberta Society is in the first year of a five-year pilot project to use a contraceptive 
vaccine to control the province’s population of wild horses, which numbers around 850.
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An Alberta group is trying to rein in the province’s wild horse population and forever end a controversial cull of the feral horses.

The Wild Horses of Alberta Society (WHOAS) has just completed the first year of a five-year pilot contraception and field monitoring program, a first of its kind in Canada.

The provincial government granted permission for WHOAS, a registered charity based in Olds, to carry out the pilot. There are an estimated 850 wild horses in the province and so far the group has vaccinated 73 mares with a Zona Stat-H contraceptive vaccine, which makes them 70 to 80 per cent less likely to conceive. Sixteen mares have also received a booster, which makes them 90 per cent less likely to conceive.

“We go out in the field with our team of volunteers and veterinarians,” said Bob Henderson, president of WHOAS. “We have a large database of herds that are in our research areas. We go out and identify a mare that has already foaled and is in a strong herd, and we apply the vaccine to her.”

The team is covering an area of 490 square kilometres around Sundre. Wild horses have been known to roam the province from the foothills of the Rocky Mountains from Kananaskis Country to Nordegg, and have even been spotted near Edson and Hinton.

The vaccine, which is used extensively in the United States, produces antibodies around the mare’s eggs, preventing sperm from fertilizing her egg. The vaccine is applied with a dart gun shot into a mare’s hips from about 25 to 50 metres away.

“The stallion will still breed her,” said Henderson, who is based in Olds. “She’s still going to be able to stay with the herd, but for three years, she won’t be able to conceive. After that time, she can foal again and put her genes back into the herd.”

WHOAS’ team of volunteers, led by equine veterinarian Bruce Stover, has completed the darting for spring 2016 and will resume darting at the end of foaling. The group is working with the University of Calgary, and signed a memorandum with the province to pursue the contraceptive program and a wild horse adoption program.

WHOAS, which receives no government funding, is bearing the entire cost of the contraception and field monitoring through private donations and volunteer service. The group raised $16,943 for the first year of the program — the total cost to vaccinate one mare is about $1,100 with donated time and equipment factored in.

By the end of the five-year pilot project, the field monitoring information will be used to determine the effectiveness of the contraceptive program.

The wild horse cull has been controversial and prompted large protests across the province. While there was no cull in 2016, 48 horses were captured in February 2015. WHOAS took in 28 horses from the cull, along with three other horses it rescued. The organization, which has created a wild horse facility on donated land, gentles and adopts out the horses, and also gelds males to prevent further breeding.

There has been no research on the impact of the horses on the rangelands or on the number of horses the environment can support. But they have been known to cause problems on private land.

“It’s usually the young studs, trying to capture themselves a girlfriend. They break down fences,” said Henderson.

WHOAS is still meeting with the government to discuss future culls.

“There is no science to support the culling,” said Henderson. “Without good scientific evidence, these random culls are counterproductive. We’re trying to convince them that the contraception project is the way to go — both long term for the horses and to benefit all the stakeholders — as the most effective way of managing the herds.”

About the author


Alexis Kienlen

Alexis Kienlen lives in Edmonton and has been writing for Alberta Farmer since 2008. Originally from Saskatoon, Alexis is also the author of two collections of poetry, a biography, and a novel called "Mad Cow."



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