Looking for Bear

I will be in Yellowstone NP for most of the next two weeks looking for grizzly bears. I have to admit grizzlies scare me. Fortunately most encounters are near the road and the safety of the car. I'm also reminded that bad encounters occur in wooded areas when they are surprised at a meal or with cubs. While the fear is rational it might be overstated. Now I have to find the bear spray and make sure it has not expired.