A concept is an abstract or general idea inferred or derived from specific instances. In this instance the concept is "Peaceful coexistence."
Two groups of fishermen show no concern with the presence of a Brown bear within close proximity. Each species, man and bear, are willing to ignore the other as they each realize that the other poses no threat to them. Although they are in pursuit of the same prey, salmon, they know that the sheer number of fish available is so high that it would be impossible for either to completely eliminate the other's potential for survival. They have all chosen to peacefully coexist.