Deer possess specialized skin structures called scent glands that act as a complex system of chemical communication. These glands produce pheromones, which are chemical signals that trigger specific social responses in other deer. Deer rely heavily on this olfactory language to navigate their social structure, identify individuals, and ensure survival. This non-verbal communication system is highly sophisticated.
Anatomical Guide to Deer Scent Glands
The deer’s body hosts several major scent glands distributed from head to hoof, each with a distinct physical location. The Preorbital Gland is found in the corner of the eye, appearing as a slit-like depression just in front of the eye. This gland secretes a fluid that helps lubricate and clean the eye.
The Forehead Gland is situated on the deer’s forehead, spanning the area between the eyes and the base of the antlers in bucks. Does also possess this gland, located between their eyes and ears. Within the nasal passages, the Nasal Glands are almond-shaped structures that empty into the nostril. These glands lubricate the nasal cavity, which allows the deer to better capture and process scent molecules.
The legs contain three types of glands. The Tarsal Glands are located on the inside of the rear legs at the hock joint. This gland is marked by a tuft of stiff hair coated in an oily deposit produced by sebaceous glands.
The Metatarsal Gland is on the outside of the hind leg, a few inches above the hoof. It is visible as an oval patch of whitish hair surrounding a central callous area.
The Interdigital Glands are positioned between the two toes of each hoof. This small sac secretes a yellowish fluid deposited on the ground with every step a deer takes.
The Role of Scent in Deer Communication
The chemical signals released by these glands convey a wide array of information. Scents from the Tarsal Glands, which are constantly exposed to urine, serve as a unique individual identifier. This scent allows other deer to recognize an individual’s gender, age, dominance rank, and overall health condition.
Secretions from the Forehead and Preorbital Glands are used to mark territory and establish social hierarchy. When a deer rubs its head on trees or branches, it leaves behind a scent that conveys its status and identity.
The Interdigital Gland secretions are deposited with every footfall, forming a scent trail. This trail allows deer to follow one another and navigate their home range.
The Metatarsal Gland may play a role in alarm signaling in some deer species. For bucks, the intensity of scent from the Tarsal and Forehead Glands increases significantly during the breeding season, known as the rut. These potent scents signal reproductive status and dominance to potential mates and rivals.
Scent Dispersal Behaviors
Deer engage in specific physical actions to actively distribute the scents from these glands into their environment. The most recognized behavior is Rub-Urination, which involves a deer bringing its rear legs together and urinating over the tuft of hair on the Tarsal Glands. This action mixes the urine with the gland’s oily secretions, intensifying the individual’s unique scent marker.
Bucks create “rubs” by rubbing their foreheads and antlers on small trees and saplings. This deposits the oily secretions from the Forehead Glands directly onto the bark, leaving a visible and olfactory mark of their presence.
The Preorbital Glands are activated when deer rub their face and eyes on overhanging branches, often called “licking branches.” These branches are typically located above ground scrapes.
When a buck creates a “scrape” by pawing at the earth with its front hooves, it activates the Interdigital Glands. The secretions are deposited into the exposed soil, adding a localized scent that communicates the animal’s recent passage.