A crossbow by definition of the federal firearms act is not a firearm. There was a thought of classifying it as a firearm at one point which is why certain people have crossbows listed on the back of their PAL. It never came to fruition. An item becomes a firearm when it's projectile reach's 500 feet per second or more as well as meets a specific muzzle energy factor.
In terms of hunting, the provincial hunting regulations classify any item used to hunt game as a firearm. This means that crossbow's are subject to all of the requirements of long guns. Namely whether it can be loaded or unloaded, encased at night, etc.
Whoever said the crossbow was a weapon is mistaken. Weapons are used to inflict harm. In the case of sport shooters, hunters, farmers, etc. Firearms are not weapons, they are tools. A baseball bat used during a game is a tool, used in a back alley to beat someone is a weapon.
Either way, when you are hunting a crossbow is considered a firearm and if there is a no discharge bylaw where you are, you cannot use archery to hunt game.