The wild turkey has a distinct and striking head and neck due to several prominent, featherless, fleshy structures. These unusual growths give the bird its recognizable appearance, especially when the skin color shifts dramatically. These unique anatomical features serve several purposes related to the bird’s social life and physical well-being. Understanding these different growths provides insight into the complex communication and biology of this large bird.
The Snood: Defining the Primary Feature
The fleshy projection that hangs over a turkey’s beak is specifically called the snood, an erectile protuberance located on the forehead. When the turkey is relaxed, the snood is often pale and contracted, sometimes measuring only a few centimeters long. This structure is highly vascular, meaning it is rich in blood vessels, allowing it to change size and color rapidly. When a male turkey, or tom, becomes excited or engages in a mating display, blood rushes into the snood, causing it to engorge, turn vibrant red, and elongate significantly.
Other Fleshy Appendages
The turkey’s head and neck are adorned with two other similarly conspicuous structures besides the snood. The wattles are flaps of fleshy skin that hang down from the bird’s chin and throat, resembling a dewlap. These structures are often a bright red color in males during the breeding season. In contrast, caruncles are the bumpy, wart-like growths that cover the bare skin of the turkey’s head and upper neck. These three distinct features are often mistakenly referred to using the same name, but their specific locations differentiate them.
Biological Role of Turkey Head Ornamentation
The collective head ornamentation functions as a dynamic signaling system within the turkey population. These structures play a significant role in sexual selection, as female turkeys tend to prefer mating with males that display longer snoods. Research indicates that males with longer snoods often have a lower burden of intestinal parasites, suggesting the snood acts as a visual indicator of overall health and genetic fitness.
The color and size of these appendages also signal dominance and mood among males. When a tom is displaying or ready to fight, the increased blood flow causes the head and neck to turn bright red, sometimes with patches of white or blue, and the snood elongates. A tom with a prominent, vibrant set of ornaments is typically deferred to by other males, establishing a clear social hierarchy.
The bare, fleshy skin of the head and neck also serves a practical function related to thermoregulation. Turkeys do not sweat, and their dark feathers absorb significant heat, so the highly vascularized skin helps them manage body temperature. Blood circulating close to the surface of the wattles and caruncles allows excess heat to dissipate into the air, acting as a cooling mechanism. Although female turkeys, or hens, also possess these features, they are significantly smaller and less prominent than those of the males.