Moles are small, insectivorous mammals that frequently tunnel beneath yards, leaving behind noticeable ridges and mounds of soil. These subterranean creatures rely on a highly developed sense of smell to navigate and hunt for food almost exclusively underground. Moles are not rodents, but they use their sophisticated olfactory system to locate prey. This article examines the specific chemical and environmental scents that attract moles to a particular area of your yard.
The Predominant Attractant: Earthworms and Insect Larvae
The greatest factor drawing a mole to your property is the scent of its preferred food source. Moles are insectivores, and their diet is dominated by invertebrates living in the soil, primarily earthworms and beetle larvae (grubs). The chemical signals released by these prey items, both living and decaying, create a strong, irresistible scent trail.
Earthworms, which constitute a large part of a mole’s diet, continuously emit scent molecules that travel through the soil’s air pockets. The movement and presence of insect larvae, such as Japanese beetle grubs, also give off distinct chemical cues. A high concentration of these invertebrates in the soil signals a readily available food source. Moles follow this high-density scent signal, consuming large quantities of prey daily to meet their metabolic needs.
The decomposition of dead insects and worms also contributes to the attractive scent profile of the soil. As these organisms break down, they release volatile organic compounds that moles are adapted to detect. This localized abundance of food odor makes a yard with a thriving population of soil invertebrates a prime target for mole activity. Moles do not eat plant roots, but they tunnel directly toward the smell of the life forms they consume.
The Scent of Ideal Habitat Conditions
Moles are also attracted by the indirect scent signals of an ideal subterranean environment. The aroma of rich, organically healthy soil is a major draw because it signifies an environment capable of sustaining high populations of worms and insects. This earthy smell indicates good soil structure, which makes tunneling easier and more energy-efficient for the mole.
The smell of damp, loamy soil is particularly attractive as it indicates sufficient moisture levels, a requirement for both moles and their prey. Earthworms and grubs thrive in moist conditions, so the strong, earthy aroma released after rainfall or irrigation indicates a successful hunting ground. This scent of moisture acts as an environmental proxy for food abundance.
Areas rich in decaying organic matter, such as compost piles, mulched beds, or decomposing leaf litter, produce a strong scent signature. The breakdown of this material creates a localized heat and nutrient source that attracts earthworms and various insects. The resulting complex odor of decomposition and high invertebrate activity signals a food-rich zone to the mole. Decaying roots and stumps similarly act as long-term invertebrate havens, creating an attractive, persistent scent.
Specialized Sensory Abilities for Subterranean Scent Detection
The mole’s ability to locate these scents is rooted in a highly specialized olfactory system. Unlike most mammals, the common mole possesses the unique capability to “smell in stereo” while navigating its underground tunnels. This means the mole uses both nostrils independently to detect subtle differences in scent concentration between the left and right sides of its snout.
By comparing the odor intensity entering each nostril, the mole rapidly triangulates the exact direction of the scent source. Research has shown that if a mole’s nostrils are artificially crossed, the mole becomes confused and unable to navigate directly toward food. This demonstrates that the spatial separation of the nostrils, though small, is functionally significant for directional hunting.
The mole’s snout is covered with thousands of minute, dome-shaped sensory receptors, which contribute to its hypersensitive sense of smell and touch. This advanced sensory apparatus allows the mole to detect the faint chemical vapors released by earthworms and grubs moving through the soil’s air pockets. This olfactory system transforms the soil’s scent profile into a precise, three-dimensional map that guides the mole’s search for food.