This video, recorded in northern Canada, says about itself:
Pack Of Wolves Hunt a Bison – Frozen Planet – BBC Earth
30 August 2017
The largest wolves on earth hunt down North America’s largest land animal.
Eight bison — four calves and their mothers — were released in mid-March on public lands in northern Colorado. A 10-month-old calf known as IVF 1 was among the newcomers: here.
Dear Kitty. Some blog 
Pingback: Blue jays against green heron in the USA | Dear Kitty. Some blog
Pingback: Books on wolves wins prize | Dear Kitty. Some blog
Pingback: Book on wolves wins prize – The Gaia Gazette
Pingback: All wolf species, video | Dear Kitty. Some blog
Pingback: Wolves slowed down by snowfall | Dear Kitty. Some blog