The wild turkey is an instantly recognizable bird, largely because of the distinctive, fleshy appendages covering its head and neck. These structures give the turkey a unique appearance, leading many to wonder about their purpose. The most prominent feature is the one that hangs directly over the bird’s beak.
The Snood: The Fleshy Projection Over the Beak
The structure that hangs from the forehead and drapes over the beak is called the snood. This highly erectile, fleshy protuberance is unique to turkeys and originates at the base of the upper bill. While both male and female turkeys possess a snood, the male’s is significantly larger and more noticeable.
The snood’s appearance is dynamic and can change rapidly based on the turkey’s physiological state. When the turkey is calm or relaxed, the snood is pale and relatively short. However, when a male turkey becomes excited, such as during a courtship display, the snood engorges with blood, turning a bright red color.
This engorgement causes the snood to elongate dramatically, sometimes hanging several inches below the beak. The turkey can actively retract and extend the snood through muscular action. This ability to instantly change the snood’s size and hue makes it a visual indicator of the bird’s mood and dominance.
The Wattle and Caruncles
The snood is only one of several fleshy structures that adorn the turkey’s unfeathered head and neck. Another prominent feature is the wattle, a flap of skin that hangs from under the chin and throat. The wattle is a pendulous dewlap that is more spread out than the snood.
The remaining numerous, bumpy, wart-like growths scattered across the head, face, and neck are called caruncles. These small, bulbous protuberances are particularly concentrated at the base of the neck.
Similar to the snood, the color of the wattle and caruncles can shift rapidly from a pale, almost whitish-blue to a vibrant red or blue when the bird is aroused or excited. These color changes are due to blood rushing into the highly vascularized tissues. Both sexes have these features, but they are significantly more exaggerated in male turkeys.
Biological Roles of Turkey Head Structures
These elaborate head structures serve multiple biological purposes, primarily revolving around communication and physical health. The most prominent function is in sexual selection, where the snood and other features act as advertisements of the male’s quality to potential mates. Female turkeys prefer to mate with males that have longer snoods and larger, more brightly colored wattles and caruncles.
A long, robust snood is a reliable indicator of a tom’s health because it correlates with a lower internal parasite load. Males with fewer parasites are able to invest more resources into developing these impressive ornaments, making them a desirable partner for passing on “good genes” to offspring. Subordinate males often defer to those with longer snoods in dominance contests, further cementing the structure’s role as a signal of social status.
The bare skin of the snood, wattle, and caruncles also plays a significant role in thermoregulation. Turkeys do not sweat, and their dark feathers absorb a lot of solar heat. The featherless, highly vascularized skin allows the bird to dissipate excess heat by moving blood closer to the surface to cool down.
This heat dissipation function is particularly important for large, active males in warmer environments. The ability of the fleshy structures to quickly change color and size is an immediate, visual readout of the tom’s excitement, dominance, and underlying physical condition.