How Pangolins Dig Burrows: Ground Pangolin Digging Behaviour

The ground pangolin (Smutsia temminckii), the only wild pangolin species found in southern Africa, spends the majority of its life in close relationship with the soil. By day it sleeps underground; by night it forages across open savanna and woodland. Between these two activities lies a third, less visible one: digging. The pangolin burrow is not a passive shelter but the product of sustained, purposeful excavation, and understanding pangolin digging behaviour reveals a great deal about how this species survives, what it requires from its habitat, and why the loss of suitable digging substrate is a genuine conservation threat.

Why Pangolins Dig Burrows

Shelter and Temperature Regulation

The savanna and bushveld habitats that ground pangolins occupy across South Africa, Botswana, Zimbabwe, and Namibia are subject to extreme temperature swings. Surface temperatures in summer can exceed 50 degrees Celsius in direct sun, while winter nights in the Kalahari regularly drop below freezing. A pangolin has no capacity to sweat and limited ability to pant effectively. Its physiological thermoregulation is relatively poor compared with many other mammals of similar size, which makes behavioural thermoregulation through burrow use essential.

Soil temperature at a depth of one to two metres remains far more stable than surface temperature, fluctuating within a narrower range across seasons and barely at all across the course of a single day. By retreating into a pangolin burrow during daylight hours, the animal passively avoids heat stress without expending energy on active cooling. In winter, the same underground chamber provides insulation against cold. The burrow is therefore not merely a hiding place; it is a physiological buffer that allows the ground pangolin to occupy an otherwise demanding thermal environment.

Safety from Predators

Ground pangolins are preyed upon by lions, leopards, hyenas, and, above all, humans. Their primary defence is to curl into a tight ball, presenting only the hard-scaled exterior to a threat. This defence is highly effective against most wild predators but entirely passive. A curled pangolin on the surface remains accessible to a determined predator and can be rolled, carried, or pried open if the predator is persistent. Underground, a curled pangolin is largely inaccessible: the narrow tunnel entrance prevents entry by large carnivores, and the animal can brace its scales against the burrow walls to resist being dragged out. The pangolin burrow transforms a passive defence into an active one.

How Pangolins Dig: Anatomy and Technique

The ground pangolin is a powerful excavator. Its forelimbs are shorter and more heavily muscled than its hindlimbs, and each forefoot carries three large, curved claws that are disproportionately long relative to the animal's body size. These claws are the primary digging tools. When excavating, the pangolin uses a raking motion, driving the claws into loose or compacted soil and pulling material back and underneath the body. The hindlimbs then kick this loosened soil further back or to the side, clearing the working space.

The animal holds its front claws in a partially curled position when walking so that the digging surfaces are protected from blunt wear on hard ground. This is the same posture that makes a ground pangolin appear to walk awkwardly on its knuckles when observed crossing open terrain. The trade-off between walking efficiency and claw preservation illustrates how completely pangolin anatomy has been shaped by the demands of digging.

Pangolin digging is not limited to burrow construction. The same claws and forelimb muscles are used to tear apart termite mounds and ant nests, which constitute virtually the entire diet. A single night's foraging may involve breaking into dozens of mounds, each requiring concentrated excavation effort. The musculature that enables this foraging also enables rapid burrow construction when the animal needs to establish a new resting site.

Burrow Depth, Structure, and How Deep Pangolins Dig

A typical self-dug ground pangolin burrow follows a sloping tunnel that descends at an angle before opening into a slightly enlarged terminal chamber. In Smutsia temminckii, this tunnel is generally one to two metres in overall depth, though the sloping entry means the horizontal tunnel length may be considerably greater than the vertical measurement. The chamber at the end is just large enough to accommodate the animal curled into a ball, with the scaled back pressed against the roof and sides of the space for additional security.

Larger species are capable of more impressive excavations. The giant pangolin (Smutsia gigantea) of central and west Africa digs burrows that can exceed five metres in length, with chambers documented as large enough for a person to enter on hands and knees. Even for the ground pangolin, burrow dimensions vary with soil type: sandy soils allow deeper and longer tunnels than clay-rich substrates, which are harder to excavate but provide better structural stability once a burrow is established.

The mound of excavated soil outside the burrow entrance is a useful indicator for researchers. It reveals the presence of an active or recently used burrow, and its volume can be used to estimate the extent of digging. However, in areas where pangolins regularly use borrowed aardvark holes, these entrance mounds may be absent or indistinct.

Multiple Burrows and Home Range Rotation

Ground pangolins do not maintain a single permanent den. Radio-tracking studies across southern African populations consistently show that individuals move between a network of burrows distributed across their home range, rarely using the same burrow on consecutive nights. Research on related pangolin species has recorded individuals rotating among twelve to forty-eight distinct resting sites over tracking periods of weeks to months.

This rotation behaviour serves several functions. By not returning to the same burrow night after night, the animal reduces the accumulation of ectoparasites such as ticks and mites within the sleeping chamber. It also prevents predators from learning to stake out a predictable location. And it allows the foraging area immediately around each burrow to regenerate ant and termite colonies before the animal returns, effectively managing its food supply across space and time.

Opportunistic Use of Aardvark and Other Burrows

Ground pangolins in South Africa and Botswana make frequent use of burrows excavated by other species. Aardvarks (Orycteropus afer) are the principal benefactors: they are prodigious diggers whose burrows are large, structurally sound, and widely distributed across suitable habitats. A pangolin can squeeze into an aardvark burrow and may deepen or widen the terminal chamber to better fit its body. Springhare and porcupine burrows are used in a similar way, particularly where aardvark presence is lower.

This ecological relationship means that the local population density of aardvarks and other primary excavators directly affects the quality of pangolin habitat. Where aardvark populations have declined, pangolins face a reduced supply of ready-made shelters and must invest more time and energy in excavating their own burrows.

Ecological Role: Pangolin Digging and Soil Health

The digging activity of ground pangolins has measurable consequences for the soil around them. Excavating a burrow brings subsoil material to the surface, exposing it to weathering processes and mixing it with organic matter from the topsoil. The tunnel itself creates a channel for rainwater to infiltrate deeper into the soil profile rather than running off the surface, improving water retention in the immediate area. As the pangolin forages, tearing into dozens of ant and termite mounds each night, it repeatedly breaks and aerates surface soil across a wide area.

These cumulative effects qualify the ground pangolin as a minor ecosystem engineer, a species whose physical activity modifies the environment in ways that benefit other organisms. Increased soil aeration supports plant root growth; better water infiltration increases vegetation productivity; and the burrows themselves provide shelter for a range of secondary occupants, from insects to small reptiles to other small mammals.

Research Challenges: Finding Pangolin Burrows

Locating pangolin burrows is one of the more persistent practical difficulties in ground pangolin research. The animals are nocturnal and cryptic, and they leave relatively little sign of their presence during the day. Researchers working in South Africa, Botswana, and Zimbabwe have increasingly relied on radio-telemetry and GPS collars to locate animals and then work back to their resting sites. Camera traps placed at known or suspected burrow entrances have proved useful for confirming active use without requiring the researcher to be physically present. Indigenous ecological knowledge has also proved valuable, with local trackers able to identify subtle surface signs of recent digging that trained biologists might overlook.

Conservation: Why Digging Substrate Matters

The ability to dig effectively depends on the physical properties of the soil. Ground pangolins prefer sandy to loamy substrates that are loose enough to excavate without exceptional effort but stable enough to maintain an open tunnel. Compacted or heavily crusted soils, common in areas subject to overgrazing by cattle, present a significant barrier. Heavy livestock pressure compacts the topsoil, reduces vegetation cover, and destroys the ant and termite colonies that pangolins depend on for food.

Habitat conversion to farmland compounds these problems. Agricultural land often lacks the structural complexity of natural savanna: fewer aardvark burrows, fewer suitable digging sites, and less prey biomass in the soil. Farmland boundaries in South Africa are frequently marked with electrified fencing, which kills an estimated one thousand pangolins per year as animals attempt to cross between habitat patches. Maintaining landscapes where pangolins can dig, where the soil is loose and undisturbed and where movement between burrow networks is unobstructed, is foundational to the species' survival.