Grizzly bears

Grizzly bears in the US National Parks have started ripping the doors off parked cars to get at the food left inside, and are wandering around close to the carparks . So to avoid hikers walking along trails and running into the grizzlies outdoor equipment shops have started selling little brass bells.The idea is that hikers should sew the little bells onto their backpacks and the bells will go “ting a ling a ling a ling” as the hikers walk along the National Park trails.
The bears will hear the bells and wont be surprised by the sudden appearance of a hiker.The hikers will know that they have not confronted a huge grizzly bear, and they will also know that there are bears in the vicinity because they will see the tell-tale piles of grizzly bear shit by the side of the trail.
How will they know that it is grizzly bear shit?

Easy, that’s the shit with little brass bells in it.