How Pangolins Find Food: Smell, Olfaction, and Chemosensation

A pangolin moving across a forest floor at night is solving a complex detection problem. Hundreds of ant and termite colony entrances dot the surrounding area. Some are worth excavating; others are exhausted or already-disturbed colonies. Some ant species have chemical defences that make them unpalatable. The pangolin’s small eyes, set in a conical skull, provide limited utility in darkness. It is navigating almost entirely by smell.

The Central Importance of Olfaction

Among all sensory modalities, olfaction is the primary guidance system for pangolin foraging. This is not merely inferred from behaviour — it is reflected in neuroanatomy. Dissection studies on multiple pangolin species confirm that the olfactory bulbs — the paired lobes of the forebrain that process smell — are proportionally large relative to total brain mass. This pattern is shared with other mammals that rely heavily on chemosensation: shrews, moles, and insectivorous bats.

The olfactory epithelium lining the nasal cavity is extensive, and the turbinate bones (scroll-like structures inside the nose) are numerous and complex, maximising surface area for odour molecule absorption. More surface area means more receptor neurons, and more sensitive detection.

Behavioural observations in wild and captive rehabilitation settings consistently show pangolins pausing and lowering their snout to soil surfaces before initiating digging at ant or termite colonies. They are sampling volatile organic compounds rising from the colony through soil pores. Experienced wildlife rehabilitators report that pangolins in enclosures often ignore artificially placed insects if colony scent is absent — direct placement without scent dispersal is frequently rejected.

The Vomeronasal Organ (Jacobson’s Organ)

In addition to the main olfactory system, pangolins possess a vomeronasal organ (VNO), also called Jacobson’s organ. This paired tubular structure is located in the nasal septum, with a separate epithelium projecting to the accessory olfactory bulb rather than the main olfactory bulb.

The VNO in mammals is primarily associated with pheromone detection — chemical signals from conspecifics carrying information about reproductive status, territory, and individual identity. In pangolins, the VNO is thought to serve dual functions: pheromone detection for social contexts, and potentially supplementary food-source chemosensing. The flehmen-like behaviour occasionally observed in male pangolins — a brief lip-curling and head-raising motion when investigating scent marks — suggests VNO involvement in social contexts.

A major caveat: detailed neurophysiological studies of pangolin olfaction are essentially absent from the peer-reviewed literature as of 2026. What is known comes from gross anatomy dissections, captive behavioural observation, and extrapolation from related insectivore studies. This is one of the largest known gaps in pangolin biology research.

The Volatile Chemistry of Prey Colonies

Ant and termite colonies produce a rich array of volatile organic compounds (VOCs) serving colony-internal functions: trail pheromones, alarm chemicals, queen pheromones, and cuticular hydrocarbons signalling nestmate identity. These compounds diffuse through soil and are detectable above colony entrances.

Different ant and termite species produce chemically distinct profiles. Pangolins across species show prey selectivity — they do not eat all available species but concentrate on a smaller subset. This selectivity is partly size-based (large colonies with many small soft-bodied workers are energetically efficient) and likely partly chemical. Some ant species with potent formic acid or alkaloid defences are avoided. How much of this discrimination occurs via olfaction versus gustatory experience on first encounter is not known.

Research on giant anteaters and echidnas — convergently evolved ant-and-termite specialists — demonstrates olfactory detection of colonial prey through soil from distances of several centimetres to short distances in open air. The pangolin’s slow, deliberate movement when foraging — distinct from its faster travel locomotion — may reflect active sniffing behaviour scanning soil surfaces for VOC signals.

Assessing Colony State Before Digging

One ecologically significant implication of high olfactory acuity is potential ability to assess colony state — whether a colony is large and active, recently disturbed, or depleted — before committing to excavation. The giant ground pangolin (Smutsia gigantea) uses massive forelimbs to break open concrete-hard mound structures; this energy expenditure is only worthwhile for productive colonies.

Captive observations suggest pangolins do abandon digging attempts when initial excavation reveals unproductive colonies, sometimes moving to a second nearby location without completing the first dig. Whether this reflects post-initiation assessment (chemical cues encountered as soil breaks) or pre-excavation olfactory assessment (decision made from surface scent before digging) has not been experimentally determined. Pre-excavation assessment would represent sophisticated use of olfaction to minimise wasted energy.

Scent Marking and Social Olfaction

Pangolin olfaction is not only directed toward prey. All pangolin species possess large perineal scent glands — paired anal-region glands producing a distinctive, strong secretion. Ground pangolins drag their hindquarters across logs, rocks, and prominent vegetation to deposit scent marks. Arboreal pangolins mark branches and fork junctions.

These marks appear to function in territorial boundary signalling and reproductive status advertisement. Male pangolins have larger scent glands than females in the species where this has been examined. Males follow and investigate scent trails left by females during oestrus, using the vomeronasal organ to assess pheromone content — the flehmen-like behaviour is most commonly observed in this context.

Camera trap studies have captured pangolins pausing extensively at locations previously visited by another individual, apparently investigating residual scent. The duration of these pauses suggests more than incidental detection — active reading of chemical information from the substrate.

Olfaction in Captivity and Rehabilitation

The practical implications of pangolin olfactory sensitivity are significant for captive management. Pangolins in captivity can be highly sensitive to novel chemical environments. Introduction of unfamiliar cleaning products, synthetic fragrances, or chemical residues on feeding equipment has been associated with feeding refusal in multiple rehabilitation centres. The recommendation from experienced keepers is to avoid all synthetic scents in enclosures and introduce novel food sources gradually, allowing olfactory familiarisation.

Stress in captive pangolins has been linked to olfactory cues. Animals where they can detect predator scent — or even unfamiliar humans — show elevated defensive curling and reduced feeding. Managing olfactory input is a welfare-optimised husbandry component sometimes overlooked in facilities focused primarily on physical housing.

For rehabilitation animals being prepared for release, exposure to natural substrate — soil, leaf litter, logs from the release site — prior to release allows olfactory orientation and may reduce post-release stress. Some programmes have adopted this practice, though systematic outcome data comparing releases with and without olfactory pre-conditioning has not been published.

Research Gaps and Future Directions

Pangolin olfactory science remains in its infancy. Unanswered questions include:

• What is the olfactory receptor gene family composition in pangolins, and how does it compare to other myrmecophages?
• Can pangolins detect and distinguish specific ant and termite species by VOC profile before physical contact?
• What is the detection range for colony odours through soil of varying moisture and compaction?
• How do the main olfactory system and vomeronasal organ divide functional responsibility in pangolin chemosensation?
• Does olfactory home range mapping — building a mental map of productive foraging sites by scent — occur in pangolins?

Addressing these questions requires neuroanatomical work (gene sequencing, MRI of intact brains), chemical ecology (VOC profiling of preferred versus avoided prey colonies), and behavioural experimentation (controlled foraging choice trials). This work has been done for giant anteaters and aardvarks. For pangolins, the rarity of research-accessible animals and priority given to applied conservation has left basic sensory biology underinvestigated.

Understanding how pangolins find food is not merely academic. Habitat quality is partly a function of invertebrate prey availability, which depends on soil chemistry, land use, and disturbance history. Knowing exactly what chemical signals pangolins track when selecting foraging habitat would make it possible to assess habitat quality more precisely than current vegetation-proxy methods allow — improving site selection for protected areas and assessment of habitat recovery for reintroduction.

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