Here is my 25 cents (adjusted for inflation :? )
I am a fishing guide and a wilderness guide, have worked as a bear guard for a seismic crew and have hunted extensively in Alaska (lived in Alaska for 33 years). I personally know of 10 bear attacks/mauling. Many were hunters (stealthing in the woods and surprising the bear), a couple were around food piles (stumbled upon a food pile that the bear was protecting), a couple were around the den in spring time, two were sow and cubs, and one was a jogger with a dog. Bear spray was not used in any of these attacks.
I don’t have first hand experience with cougars (none in Alaska that I know of).
So, I guess that I might have a dog that will hunt in this thread?
My opinion based on experience, study and others:
Brown/Griz attack mostly defensively. There will likely be false charges before the mauling, certainly many warnings (not always the case; i.e. 2 friends around the bear dens didn’t have any warning, den was discovered after the attack. Also, sows with cubs will rarely offer a false charge). In a situation where the bear is offering warnings, bear spray may be effective. In these cases, however the bear is typically surprised because they didn’t know you were coming, i.e. they are up wind. So if you discharge your bear spray upwind, guess what??? you are now disable and cajun spiced. It has been documented that bears are attracted to pepper spray that has been sprayed on the ground, so they like it, just not in their face. If a bear is making a full charge, running probably around 35 mph or so, pepper spray is not going to slow them down.
By the way, it has been determined that irregular noise will alert a bear to your presence. A bear bell, on the other hand, is so constant that the bear will “tune it out”. So, in my opinion, forget the bells, talk out loud with companions, break a stick or whack a stick or whatever on occasion… Bears love dogs, they taste just fine and make a fun challenge. They also will go out and find the bear and swiftly return to the owner, thus more food for the bear. Seriously, the one friend that was mauled while jogging had his dog with…the dog ran ahead and encountered the bear and then ran back to the owner with the bear in close pursuit… the bear beat the jogger up quite extensively (he lived but is permanently scarred).
Black bears (and presumedly cougars???) attack for food; i.e. predation. In these cases the critter will actively and stealthly stalk the prey and look for an opportunity to attack. I agree with the posts about the cats that if a bear/cat wants to attack, you won’t have any warning. In these cases, the bear spray is likely not effective.
Now, I am reluctant to disclose this information because I am quite dissatisfied with myself and the performance. As a hunter, I have had to shoot 2 black bears with my handgun. This is a .41 magnum, with HOT handloads. In both cases the shots turned the bears but didn’t kill the bears. Indeed, it took many shots to finally dispatch the bear. I have sworn since that I would not, if at all possible, shoot a bear with my handgun again. Presently, I carry a 12guage shotgun with a slug barrel. Certainly the handgun is more convenient to carry, but not as effective. The .44 mag is a better gun as is the .50 but still a bit light for stopping an angry bear. Indeed, an Alaskan sports editorialist/writer for the Anchorage paper was carrying a 454 Cassul, got one shot off before the bear proceeded to chew on him a bit… didn’t kill the bear and the bear was never found.
So all of that to say that your best defense in the woods are your senses, eyes, ears, nose, and common. Be bear aware, watch for signs, always look ahead and around corners as much as possible, avoid situations where you are turning a blind corner into the wind. Be cautious around flowing streams where the sound will drown your sound as well as the bears. Keep all food out of your tent. Use bear proof containers and suspend if in high bear activity areas. Avoid travelling alone (most predator attacks are on soloists). Be well armed (12 guage or very high powered rifle; i.e. .338 or larger) if in high risk areas or involved in high risk activities (i.e. hunting, wildlife photography, etc.).
Bears are very unique and majestic animals. I truly love watching bears in the mountains, or fishing the streams… just being bears. They are incredibly intelligent and adaptive. It certainly is possible to get along using whatever method and means necessary to be bear aware/safe.
Happy trails…