Everybody wants to see bears (black and grizzly bears)! As a guide I certainly wish to facilitate the experience! But bears are not equally visible all year-round. Obviously Winter is the most difficult season to see bears, as they may be in winter dens hibernating.
Spring is undoubtedly the best season to see bears. At that time they are frequently foraging in open areas, feeding on emerging vegetation. Alternatively they may be hunting new born herbivores (elk, bison, deer, and pronghorn give birth at this time and bears seek, and search for, these calves and fawns).
In Summer all herbivores are spreading out over larger landscapes to maximize their opportunity to find the most nutritious vegetation. Considering that bears are true omnivores, they too may spread out to find the most nutritious plant materials.
By late Summer and early Fall, berries may become a major food source. Huckleberries, buffaloberry, chokecherry, service berry, wild currants, and snowberry are all good examples. Later in Summer, whitebark pine nuts (similar to the pine nuts we see in salads) may become a popular food source. During these periods, bears are feeding in shrub and forested areas.
The fact that they are in a closed canopy plant community (inside the forests) they can be very diffcult to simply see. To spot a bear at a safe distance and to be able to observe natural behaviour takes some luck. However, we can increase our odds! We often drive or hike to overlooks which can view forest margins. By spending some time scanning the edges of the forests we can get "lucky" and observe some incredible bear behaviour!
It is very impressive how dexterous a bear can be! Using lips, teeth, tongue and paws, they can pluck individual berries from branches or strip them from branches in bunches. When feeding on whitebark pine nuts, black bears often climb to the topmost branches of the whitebark pine trees to get at the cones (which are situated on the outermost tips of the branches)! The contortions they go through are amazing! Bending treetops, flexing branches, extended reaches of clawed paws, legs wrapped around spindly trunks; they pluck cones and either drop them to the ground or eat in the tree. The contortions and dexterity are super fun to watch! Sometimes they chew, or break, the branch off and drop it to the ground.
This type of behaviour is not always visible on and annual basis. First: there must be whitebark cones. Cones (and berries) are not abundant every year and it does not help that many whitebark pine trees are now dead. [This is a separate subject, but understand that whitebark pine trees are in trouble due to a variety of factors. This is a major loss of food for all bears.] Second: you have to be looking in the right place at the right time and have a bear foraging for this food. However, when it works, it can be one of the greatest wildlife sightings of a person's life!
One final consideration: carcasses. If wolves make a kill, bears will smell these carcasses and travel long distances to find them. Likewise, the bison rut often results in mortal injuries to some of the male combatants. When these guys die they will also attract bears. Carcasses may take patience as well, but they can be great sites to observe bears. Just make sure you have good optics! You don't want to be too close!