This Turkey Tuesday is about the unique characteristics on a wild turkey’s head. Us turkey hunters cherish the colors of a tom’s head in spring – the brilliant reds, blues, and whites that in so many ways symbolize turkey hunting. But there’s more to a tom’s head than colors! The skin on the head and neck is carunculated, which means that it covers fleshy protuberances called caruncles. These caruncles include the major caruncles at the base of the neck, and the minor caruncles that are less obvious but occur all over the bird’s neck and head. Toms can adjust blood flow to the caruncles by contracting the blood vessels within them, so the caruncles change color as the bird’s mood changes – in that way, the caruncles obviously serve as a secondary sexual characteristic – hens are able to obtain information from assessing a tom’s caruncles. Toms have little feathering on their heads which allows dissipation of heat, but the larger caruncles and even the dewlap under the throat allow for further heat dissipation. Therefore, the blood that flows through them when a tom is aroused and displaying cools quickly, preventing the bird from overheating. Lastly, there is evidence in some birds that males with more colorful caruncles are more resistant to disease, although it’s unclear if this is true with turkeys. The take home is, the head of a wild turkey contains many features that help birds not only attract attention, but also meet important daily functions to ensure their survival.
Pic by Matt Addington.