Moles are subterranean insectivores whose existence depends on their ability to dig. These mammals have powerful, shovel-like forelimbs and a cylindrical body shape adapted for moving through soil. A mole’s relentless tunneling is necessary for survival, providing food, shelter, and a regulated environment. Their underground networks are their habitat and the means by which they hunt for earthworms and insect larvae. The answer to whether a mole reuses its tunnels is complex, depending entirely on the specific function of the subterranean passage.
Defining the Mole’s Tunnel Network
A mole’s underground environment is an intricate, multi-tiered system where different structures serve distinct purposes. Tunnels are categorized by depth, structure, and permanence. Deeper tunnels, known as main or active runs, form the permanent infrastructure of the mole’s home range.
These runs can descend up to a meter below the surface, connecting various parts of the territory. They lead to specific chambers, including the nest for resting and raising young, and larders for storing paralyzed earthworms for later consumption. Excavated soil from these deep sections creates the characteristic volcano-shaped molehills on the surface.
Permanent Tunnels and Regular Patrolling
The deep main runs are consistently reused and maintained, functioning as the mole’s travel route between its nesting chamber and foraging zones. These tunnels passively trap prey; earthworms and other invertebrates naturally fall into the open passage, turning the tunnel into a pitfall trap. The mole patrols its main runs regularly, often several times a day, to collect trapped prey and ensure the tunnel remains open and free of debris. If a main run is damaged, the mole quickly repairs it, demonstrating the structure’s importance as a reliable food source and protected path.
Temporary Foraging Runs
In contrast to permanent tunnels, shallow, surface-level runs are temporary and disposable. These runs appear as raised ridges in the topsoil and are created as the mole explores new hunting grounds near the surface. Moles excavate these exploratory tunnels rapidly, sometimes digging up to 18 feet in an hour, especially in loose, moist soil.
The goal of these shallow runs is immediate foraging, allowing the mole to intercept prey concentrated near the surface. Once the food source is depleted, these superficial passages are often abandoned. Because they are close to the surface, they are prone to collapse and are not maintained or reused like the deep structural runs.