Moles are small, subterranean insectivorous mammals adapted for life entirely beneath the soil. They are often mistakenly assumed to be strictly nocturnal because they are rarely seen above ground. Moles are active throughout both the day and the night, making them neither purely diurnal nor nocturnal. This continuous activity is driven by a unique physiological need, regardless of the time of day or sunlight.
The Truth About Mole Activity Patterns
Moles follow a polyphasic activity pattern, meaning their daily cycle consists of multiple short periods of activity and rest. This cycle typically consists of approximately three to four hours of active foraging and tunneling, followed by a period of rest lasting a similar duration. Because they adhere to this schedule, a mole is just as likely to be actively digging and searching for food at noon as it is at midnight.
This continuous cycle ensures the mole maintains a necessary energy equilibrium. The brief resting periods allow for digestion and conservation of energy before the next bout of strenuous tunneling begins. While activity is continuous, people often notice an increase in new surface disturbances during the cooler, damper hours of early morning and late evening. This tendency is less about light and more about optimal soil conditions for easy digging and the movement of prey near the surface.
Driving Force of Mole Behavior
The primary reason a mole cannot afford a traditional sleep schedule is its exceptionally high metabolic rate, which demands a constant intake of calories. As a small endotherm, the mole must burn a significant amount of energy to fuel its strenuous lifestyle of continuous digging. This high-energy requirement means a mole can only survive without food for a short period, often no more than six to eight hours.
Moles are voracious predators whose diet consists primarily of earthworms, insect larvae, and grubs found within the soil. They consume a staggering amount of food, often eating nearly their body weight in prey every 24 hours. To meet this intense caloric demand, their tunnel network functions as a series of “worm traps” that they patrol regularly. Some species possess a paralytic toxin in their saliva, allowing them to immobilize earthworms and store them alive in underground larders for later consumption.
Anatomy of a Mole Tunnel System
Mole tunnels are functionally divided into two distinct systems: temporary feeding runs and deep, permanent galleries. Surface feeding runs are shallow, temporary, and often visible as raised ridges in a lawn, created as the mole searches for prey just beneath the grass roots. These tunnels are used once or twice and are not maintained consistently.
In contrast, the permanent galleries are deep, stable tunnels that function as the mole’s main thoroughfares, nesting chambers, and food storage areas. These deeper networks are excavated by pushing soil upward to the surface, which creates the characteristic cone-shaped piles of dirt known as molehills. The molehills are not the entrance or exit to the tunnel system but rather the byproduct of constructing and maintaining the fortress-like structure far below the surface.