If a cougar is going to attack, it always attacks from behind.
Therefore, the best defence is to always drag a dead rabbit behind you on about 5 m. of bungee cord. That way, if you feel a big tug on the string, you have plenty of time to call Fish & Wildlife on your cell phone while the cougar eats the rabbit!
As a matter of fact, I think I should market that idea. If some guy can get rich selling moose whistles that you stick on the roof of your car, I should make more money than Bill Gates on dead rabbits and bungee cords. Too bad I never thought of it while the Liberals were in power; I could have imported rabbits from Quebec and got a three bazillion dollar federal grant!