BANFF – At least 16 new bison babies were born this spring in the heart of Banff’s backcountry, bringing the herd’s total number to 66 animals.
The little reds, as they are nicknamed, were born from early May through early June, but Parks Canada’s bison team didn’t get a visual on the herd in the remote Panther Valley until later in June.
Parks Canada wildlife officials say the new additions to the herd, which will soon start to turn more of a chocolate brown colour like their parents, appear to be thriving, however one of the 16 calves has died, and there's still a chance more have been born.
“It’s really exciting,” said Saundi Stevens, a resource conservation management specialist for Banff National Park working on the bison reintroduction project.
“We kept our distance and used spotting scopes, but certainly they’re looking really healthy.”
Bison, considered a keystone species that help hold an ecosystem together, were absent from Banff National Park for about 160 years before being brought back as part of a $6.4 million reintroduction project four years ago.
Parks Canada translocated 16 plains bison – 10 young females and six young males – from a disease-free herd in Elk Island National Park east of Edmonton to a 16-hectare soft-release fenced pasture in the Panther River Valley on Feb. 1, 2017.
For the first 16 months, bison were held in the fenced area in an attempt to anchor them to their new home before their release into the greater 1,200-square-kilometre reintroduction zone in the remote eastern slopes of Banff in summer 2018.
For the most part, the bison herd stays within the large reintroduction zone, which is fenced off in strategic locations to keep the animals from heading out onto Alberta provincial lands.
Stevens said the bison population is seeing an annual growth rate of about 33 per cent, noting this is considered good for any ungulate population.
“The rate at which the herd is reproducing is a pretty good indication of how they are doing and how healthy the herd is,” she said.
Another good sign is bison have returned to more normal calving patterns this year and last, including higher calving rates. Prior to 2020, the herd appeared to be out of a normal rhythm, giving birth throughout summer and even into fall.
Based on images collected from remote cameras in the backcountry, Stevens said it looks like the first calves began arriving in early May, which is a more typical birthing period for bison.
She said new remote camera data should show up soon, so there could be more births to report.
“Years previously, that cycle had been kind of out of sync, but it seems the last couple of years they’re right back to their normal calving cycle,” she said.
“This is a really good indication that the herd is adjusting really well to the landscape and the breeding season, and everything is starting to happen when it should.”
Through the use of cameras to monitor the herd, and follow-up field observations, researchers have confirmed at least one calf has died.
It likely died under natural circumstances, such as predation or injury, or died as a result of this harsh mountain environment through exposure to many natural hazards including severe weather, steep terrain and challenging stream crossings.
“We just don’t know what happened at this point,” Stevens said.
“We did see that calf with the cow on the camera, and then over the course of two days from staff observations in the field, she did not have a calf with her.”
It is possible the bison calf fell victim to a wolf; however, there has been no sign that wolves have started to hunt on Banff’s reintroduced herd, though it’s likely only a matter of time.
In the Yukon, more than 20 years went by before wolves learned to hunt bison that were reintroduced in the late 1980s as part of a national program to recover endangered species. Wolves reintroduced to Yellowstone National Park in the United States in 1995 took just two years to make their first bison kill.
In Banff, the two species have definitely been sizing each other up from the beginning. Shortly after the herd’s release into the larger reintroduction zone in summer 2018, GPS collar locations showed the main bison herd was approached many times by a radio-collared wolf.
Researchers say the opposite has happened too, with remote camera images in the Panther Valley showing a brash bison bull pursuing two wolves, and the herd and wolves walking a trail at night within minutes of each other in both directions.
Stevens said it is not yet known how long it will be until the age-old dance between predator and prey resumes and wolves start actively hunting Banff’s bison.
“There hasn’t been much change in our knowledge in that, mostly because we don’t have any radio-collared wolves at this point, and we haven’t for the last year,” she said.
“But we’re not seeing any radical movements from bison on their GPS collars to indicate that they are being harassed and pushed around by wolves at this point.”
There are currently seven bison fitted with GPS collars so researchers can track the animals and see what habitat is important to the herd.
Because bison love to rough-and-tumble, rolling and wallowing in dirt and rubbing and scratching against trees and rocks, it didn't take long for many of the initial collars to break off.
Last fall, with animals to collar to reach a commitment to have at least 10 per cent of the herd radio collared in the initial years of the project, Parks darted bison from horseback in order to get new collars on them.
“We can glean a lot of information from radio-collar data that can help shape and inspire other reintroduction projects elsewhere in terms of how bison are navigating a new novel landscape,” Stevens said.
“Those collars also alert us to when the bison might be approaching the park boundary, and with that information, we can get people on the herd and we can haze the animals back deeper into the reintroduction zone.”
Apart from a few instances where determined bulls ventured outside the reintroduction zone, few have made it onto unprotected lands.
The reintroduction plan commits to keeping bison off provincial and private lands. One wandering bull was destroyed and two others relocated so far during the program.
“It’s been over a year since we’ve had to get on the ground and gently move the animals,” Stevens said. “Again, it’s a really strong indication that the herd is really adapting well to their new home range.”
As part of the project, drift fences designed to allow other wildlife such as wolves and bears to pass were strategically placed at locations along the boundary zone to prevent bison from leaving the park.
“The fences are an integral piece and are working really well because they do explore the outer boundaries of their zone,” Stevens said.
“They are coming to the fence, but what we’re seeing now is they are reaching the fence, and the fence is just deflecting them, and they are turning around and heading back deeper into the park.”
Bison herds once numbered as many as 30 million across North America, but nearly became extinct within a single human lifetime. Although many factors led to their near-disappearance, over-hunting was the main cause that left fewer than 1,000 bison.
In the Banff area, bison didn’t roam in the vast herds that were common on the plains, but even in low numbers they helped shape ecosystems as the historically dominant grazers.
They alter landscapes in ways that benefit many other plants and animals. For example, bison fur provides insulation for bird nests, bison grazing creates habitat for elk, and they provide a rich source of nutrients for scavengers, bears, and wolves.
“They are an amazing species to see in the backcountry,” Stevens said. “We’re seeing some great things on how they are already shaping the landscape.”
In 2022, Parks Canada will assess whether to continue or abandon the bison project, but based on what appears to be a thriving herd, it is highly likely Banff’s bison are here to stay.
