Wolves primarily rely on smell to detect and track prey. Their powerful olfactory system helps them pick up scent trails, locate animals that are out of sight, and assess the presence of prey across large territories.
Smell is particularly valuable because wolves often hunt in forests, darkness, snow, or uneven terrain where vision is limited. In one study summarized in the literature on gray-wolf hunting, wolves detected moose by scent more often than by sight. They can also follow the odor left by a moving animal rather than needing to see the prey directly.
That does not mean wolves ignore their other senses. Hearing helps them detect movement and communicate with pack members, while vision becomes crucial during pursuit and the final attack. Wolves combine all three senses, but smell is the standout sense for finding and identifying prey at a distance.
Their noses also serve social purposes: wolves use scent from urine, feces, and glandular secretions to mark territory and communicate information about identity and reproductive status.