The Yukon game synopsis (
https://yukon.ca/sites/yukon.ca/files/env/env-yukon-hunting-regulations-summary_0.pdf) has some interesting statements about hunting of bison. Their regulations are written without shading the edges of probabilities.
p.23 - It’s against the law to hunt wood bison with a bow
p.26 - Under no circumstances can you kill a moose, caribou,
bison, sheep, goat, deer, elk or bird in defence of property
p.37 - Firearm requirements
X A centrefire rifle, .30 calibre or larger, with minimum 180 grain bullets (premium
bullets strongly recommended) and minimum 2,800 ft./lb. energy at the muzzle.
A .30-06 calibre is the baseline rifle.
OR
X A black powder rifle, .50 calibre or larger, firing an elongated bullet with a minimum
90 grain charge.
OR
X A black powder rifle, .54 calibre or larger, firing a round ball with a minimum
120 grain charge.
Hunters using a black powder rifle must have a centrefire rifle that meets the firearm
requirement for hunting wood bison as back up.