Pangolin Scent Glands and Territory Marking Behaviour

Pangolins lead largely invisible lives. They are nocturnal, solitary, and extraordinarily secretive — animals that researchers can track for months via GPS collar without ever observing them directly for more than a few minutes. Yet despite this invisibility, pangolins communicate. They leave chemical messages for one another across their territories using scent glands, urine, and fixed latrine sites. Understanding this system gives us a window into the social structure of one of the world's least-understood mammals.

Pangolins as Solitary Animals: What That Really Means

When biologists describe pangolins as solitary, they do not mean the animals exist in complete isolation from others of their kind. They mean that pangolins do not form stable social groups, do not travel together, and do not engage in cooperative behaviours such as communal defence or group foraging. Adults interact directly with conspecifics — other members of their own species — only during mating, and mothers maintain contact with dependent offspring until weaning. Beyond these contexts, individuals avoid one another.

This solitary organisation is not unusual among mammals. Many nocturnal, insect-eating species with large home ranges follow a similar pattern. What makes pangolins particularly interesting is the degree to which scent communication substitutes for the direct social interactions that other animals use to maintain territory boundaries, coordinate reproduction, and assess the status of neighbours. A pangolin's social world is built from chemical messages left and read in darkness, by animals that may never physically encounter one another.

Location and Nature of Pangolin Scent Glands

Ground pangolins (Smutsia temminckii) and other pangolin species possess anal scent glands — paired secretory structures located at the base of the tail, near the anus. These glands produce a musky secretion that can be deposited deliberately during defecation or expressed during an intentional scent-marking event. The composition of anal gland secretions is complex, containing volatile fatty acids and other compounds that appear to encode individual identity information, sex, and potentially reproductive status.

Urine plays a complementary role in pangolin chemical communication. Urine deposition during foraging routes appears to mark paths rather than fixed sites. Faecal deposits at specific latrine locations — used repeatedly by the same individual — are a more structured form of chemical marking. The physical accumulation of faecal material at latrines creates a persistent, visually identifiable mark as well as a scent cue, providing a double signal to any investigating individual.

The Pangolin's Defensive Spray

Separate from the territorial scent-marking function of the anal glands is their role in defence. When severely threatened and after its scale armour has failed to deter a predator, a pangolin can express its anal glands forcefully, producing a pungent secretion. This is analogous in broad principle to the defensive spray of a skunk (Mephitis mephitis), though far less potent in terms of range and irritant chemistry. The pangolin's secretion does not contain the thiol compounds responsible for the skunk's notorious effectiveness; it is unpleasant rather than disabling. Nevertheless, it appears to be sufficient to discourage some predators at close range, and it may serve to mark the predator in a way that communicates the encounter to other pangolins visiting the same area later.

How Pangolins Deposit Scent

Researchers observing GPS-collared ground pangolins in South Africa have documented several distinct scent-marking behaviours. The most straightforward is simple urination during movement — the animal pauses, urinates on the ground or on vegetation, and continues. This appears to be a routine behaviour rather than a deliberate territorial act, though the chemical signals deposited may still carry information readable by passing conspecifics.

More deliberate marking involves the animal making contact between its anal gland region and a fixed substrate: a rock, a termite mound, the base of a tree, or a prominent landmark feature. The pangolin positions itself with the hindquarters against the surface and performs a rocking or rubbing motion. This deposits gland secretion on a surface that is likely to be revisited by the same individual and investigated by others moving through the area.

Latrine site use is the most structured behaviour in the scent-marking repertoire. Individual pangolins return repeatedly to the same defecation sites — sometimes over many months — accumulating deposits that serve as persistent, chemically rich communication points. Latrine sites are typically located near territory boundaries or at landscape features that serve as natural waypoints in the nocturnal foraging circuit.

Latrine Sites as Communication Hubs

The significance of pangolin latrine sites extends beyond individual territory marking. GPS tracking studies in Zimbabwe and South Africa have revealed that latrine sites located at territory boundaries are visited not only by the resident animal but by neighbouring individuals of both sexes. This overlap turns latrine sites into something resembling a chemical message board: information about the identity, sex, and reproductive condition of multiple individuals in the area is accessible to any pangolin that investigates the site.

In some cases, a single latrine site has been found to carry scent deposits from three or more different individuals over a monitoring period of several months. This suggests that latrine sites are not purely territorial markers — exclusive statements of occupancy by a single animal — but also nodes in a network of chemical communication that allows the broader local population to assess one another without direct contact. The system is extraordinarily efficient: a solitary animal can gather information about multiple neighbours simply by visiting a single well-used latrine site.

Male Versus Female Scent Marking

Differences in scent-marking behaviour between male and female pangolins have been documented in GPS tracking studies, though the sample sizes remain small given the difficulties of the research. Males appear to mark more frequently than females, with more deliberate gland-rubbing events recorded per tracking night. This pattern aligns with observations from other solitary mammals: in species where males compete for access to females distributed across a landscape, frequent and prominent chemical marking of a territory confers reproductive advantages by advertising presence and status to potential mates and by deterring same-sex competitors.

Female marking behaviour is less well characterised. Female ground pangolins appear to use latrine sites and urine marking but with lower frequency and less deliberate substrate selection. One interpretation is that females are primarily marking to maintain awareness of their own territory boundaries relative to neighbours, rather than engaging in the more competitive signalling that males appear to perform.

Home Range Overlap and Social Spacing

GPS telemetry data from ground pangolin studies in South Africa — notably from populations in Limpopo and the Northern Cape — shows that male home ranges are typically larger than female home ranges and overlap substantially with one or more female territories while showing minimal overlap with the territories of other males. This arrangement is consistent with a resource-defence polygyny model: males maintain large territories that encompass multiple female territories, gaining mating access to several females in exchange for the energetic cost of ranging over a larger area.

Same-sex territory overlap is limited in ground pangolins. Where male ranges do overlap, the overlap tends to occur at the edges of territories rather than across core use areas. Latrine sites appear to be particularly concentrated at these boundary zones, which supports the interpretation of latrines as inter-individual signalling points rather than purely intra-territorial markers. In Zimbabwe, researchers working with Endangered Wildlife Trust (EWT) have documented male-male encounters at shared latrine sites during the mating season — brief, apparently non-aggressive assessments followed by one animal departing — suggesting that the chemical information available at latrines allows individuals to make social assessments without escalating to direct confrontation.

Research Challenges and What We Still Do Not Know

The study of pangolin scent communication faces substantial methodological challenges. Direct observation of free-ranging pangolins is extraordinarily difficult: the animals are nocturnal, move through dense bush or woodland, and react to observation by freezing or retreating into burrows. Camera trap footage of scent-marking events exists but is limited. Most of what is known about marking frequency and site selection comes from GPS tracking combined with field sign surveys — researchers follow GPS point clusters to identify latrine sites and marking substrates, and document what they find.

The chemical composition of pangolin anal gland secretions has received very little formal analysis. A small number of studies have described the general nature of the secretions, but the specific compounds responsible for encoding individual identity or reproductive status have not been characterised. This gap limits our ability to understand precisely what information pangolins are communicating and how conspecifics decode the chemical signals they receive.

Comparison with Other Solitary, Scent-Marking Mammals

Pangolins are not alone in relying on chemical communication to manage a solitary social existence. The aardvark (Orycteropus afer), which shares much of the ground pangolin's range in southern and eastern Africa, is similarly solitary and uses anal gland secretions and urine to mark territory boundaries. The honey badger (Mellivora capensis) employs eversion of its anal pouch to deposit strong-smelling secretions on grass and rocks — a system strikingly similar in principle to pangolin gland rubbing, though the honey badger's secretion is considerably more pungent. Comparing these systems suggests that chemical communication is a convergent solution to the problem of maintaining social organisation among animals that cannot sustain the energetic costs of group living.

Conservation Relevance of Scent-Marking Research

Understanding scent marking behaviour has practical implications for pangolin conservation that extend beyond academic interest. Data on home range sizes derived from GPS tracking informs the minimum viable territory size that a pangolin population requires. When those territory sizes are known, conservation managers can assess whether a given protected area is large enough to sustain a viable breeding population, or whether corridor connectivity to adjacent habitat is required.

Latrine site locations identified during field surveys can serve as non-invasive monitoring points. Researchers can visit known latrine sites to collect faecal DNA samples for population genetic analysis without needing to capture or handle the animals. As genetic tools become cheaper and more powerful, this approach offers a scalable, low-disturbance method for monitoring pangolin population density and connectivity across a landscape — one that depends entirely on understanding where pangolins choose to leave their chemical messages.