Holes in the ground often spark curiosity about their creators. While some are temporary foraging sites, many serve as entrances to complex underground homes, providing shelter, safety, and a place to raise young. A variety of animals, from tiny insects to larger mammals, are skilled excavators, each digging for specific purposes. Understanding the characteristics of these subterranean structures can help identify the unseen occupant.
Key Features of Animal Holes
Identifying the animal responsible for a hole begins with observing its characteristics. The size, particularly its diameter, offers a primary clue, as different animals create openings of varying widths. The shape of the entrance, whether round, oval, or irregular, can also provide insight; some animals create holes wider than they are tall, while others produce perfectly circular openings.
Beyond the entrance, examine the surrounding area for additional evidence. The presence and configuration of excavated soil, often called a mound or spoil heap, can be highly indicative. Some animals create distinct volcano-shaped mounds, while others leave crescent-shaped piles or no visible dirt. Look for other signs such as animal tracks, droppings, or disturbed vegetation nearby, as these offer further confirmation. The hole’s location, such as near foundations, under trees, or in open lawn, also provides valuable context.
Mammalian Architects of Underground Homes
Many mammals are adept burrowers, constructing intricate underground networks for various life stages. Groundhogs, also known as woodchucks, create large burrows, typically with a main entrance featuring a distinct dirt mound and several other exits. These main openings are usually between 10 and 12 inches in diameter. Their burrow systems can be extensive, reaching up to 65 feet in total length and 6 feet deep, with multiple chambers for nesting, raising young, and hibernating.
Skunks often dig smaller, conical, shallow holes, typically 3 to 4 inches in diameter, when foraging for insects and grubs in lawns. These holes may appear as disturbed earth without a significant mound. Moles are recognized by their distinctive raised tunnels, or “runs,” which are shallow subsurface pathways, and volcano-shaped molehills, mounds of fine soil pushed up from vertical shafts. These molehills typically range from 2 to 12 inches tall.
Voles, small mouse-like rodents, create small, neat holes, typically 1 to 2 inches wide, often found near plants. A key sign of vole activity is the presence of shallow, visible surface runways, about 1 to 3 inches wide, connecting these holes, often lined with clipped grass or leaves. Rabbits also dig burrows, sometimes called warrens, which can have multiple openings and chambers, often concealed and sometimes with fur near the entrance. These burrows are typically smaller than groundhog holes.
Badgers construct large, oval-shaped holes, often around 12 inches wide by 10 inches high, with significant, often rocky, dirt mounds. Their underground systems, called setts, can be extensive, with multiple entrances and tunnels that may stretch over 160 feet. Foxes create dens, or “earths,” which are medium-sized, often oval holes, around 7 to 8 inches in diameter. These dens frequently have multiple entrances, and while excavated dirt may be present, it can appear trampled. Foxes often repurpose existing burrows, such as those made by groundhogs.
Unexpected Diggers and Their Tunnels
Beyond mammals, other animals also create holes. Certain insects are notable excavators; for example, cicada killer wasps dig large, perfectly round holes, often half an inch to one inch in diameter, with a distinct spoil pile. Ant colonies are known for their small mounds of fine soil, indicating an intricate underground network. Various beetle larvae can also create small, irregular holes as they move through the soil.
Reptiles and amphibians occasionally create or utilize burrows. Some snakes may use existing burrows for shelter or dig shallow retreats. Turtles, particularly females, dig flask-shaped nests in the soil to lay their eggs, which are then covered, leaving a disturbed patch of earth. These nests are typically dug in sandy or loose soil.
Birds also contribute to the landscape of holes. Bank swallows and belted kingfishers are known for digging nests into vertical earthen banks near water. Bank swallow burrows are typically 25 to 35 inches long, while kingfisher burrows can extend 3 to 6.5 feet into the bank, ending in a chamber.
Chipmunks dig small, neat holes, often found at the base of trees or rocks, sometimes with a small, discreet pile of dirt. Rats also create burrows, often 2 to 3 inches wide, typically near structures or food sources, with smooth, well-used entrances.
Your Guide to Identifying the Hole Maker
To identify the animal digging a hole, observe its characteristics. Note the hole’s diameter, shape, and whether it has a distinct mound of excavated soil. Consider the hole’s location, such as open areas, near structures, or in dense vegetation. Look for additional clues like tracks, droppings, or signs of feeding or disturbed plants nearby. Combining these observations will help narrow down the possibilities, but always maintain a safe distance and avoid disturbing active burrows.