Extract from guide book for walkers in the Rocky Mountains:
‘There are two types of bear in the Rockies, brown bears and grizzly bears.
Both are secretive creatures but will certainly attack if startled.
Therefore it is a good idea to announce you are there by making a gentle sound eg. by attaching tiny bells to your clothing.
It is also advisable to carry a pepper spray in case of a close encounter.
The droppings of these bears can tell you which kind is close by.
Brown bear droppings usually contain berries and squirrel fur.
Grizzly bear droppings may contain tiny bells and smell of pepper spray…..”