When spring arrives, wild turkeys begin the mating game. Groups gather in meadows and fields – and sometimes in the middle of the road. Males puff up their iridescent feathers, fan their tails, and drag their wings on the ground in a contest for reproductive rights. Their faces and necks take on iridescent shades of blue and red.
Once rare and elusive denizens of America’s backwoods, these heaviest of the gallinaceous birds (chickens and their kin) have gone to town. Wild turkeys live in the residential areas around my home in Madison, Wisconsin.
A few years ago I was so fascinated by their elaborate courtship shows that I started photographing them – and as I’ve learned, there’s more going on than meets the eye.
For starters, a feather turkeys flock together. Males, called toms, can form lifelong herds with their mates. dr Alan Krakauer, a biologist and fellow photographer, studied this as a graduate student at the University of California, Berkeley. He discovered that males in a herd were full to half siblings. These bands of brothers worked together to court females or hens and to drive off competing males.
Remarkably, however, only the dominant male mated and fathered offspring. The subordinate brothers served as “wingmen,” “bodyguards,” or “backup dancers” to support Dr. Using Krakauer’s colorful descriptions. “They have a supporting role, I think,” he said.
Despite the potential for lifelong celibacy, wingmen benefited from the arrangement, Dr. Krakauer out – at least according to the crude calculation of evolution. On average, dominant males with wingmen produced seven offspring per season, while solo males produced fewer than one. Because the males were closely related, these seven offspring contained more genes from the wingmen than if they had sired a single chick themselves.
“They’re helping their brother get a lot more wives than either of them would get on their own, so this collaboration seemed particularly helpful,” explained Dr. Kraków. “That seemed to come as a surprise to people at the time.”
Anyone who has had a brother knows the vicissitudes of fraternal relationships. While brothers generally cooperate during the mating season, fierce fighting breaks out at other times as they compete for rank. Turkeys have impressive weapons: large bodies, powerful wings, and spurred feet. Once I saw a fight so intense that spit flew like a boxer being knocked out.
While males are aggressive towards each other, they are not aggressive towards females and do not force copulations, despite being twice the size of their mating partners. While the males can strut around with abandon, the females ultimately choose their mates. They are picky about partners and they know what they want: men with long headbands.
Snoods are the finger-like, fleshy protuberances that fall over a turkey’s beak. The animals can contract and relax muscles and blood vessels in the head and neck, resulting in changes in length and color of the organ. A tomcat with a long red snood attracts the attention of hens like flies to honey — though hens, to their credit, manage to be shy.
dr Richard Buchholz, a professor at the University of Mississippi, has spent his career studying wild turkeys. He examined the role played by various male ornaments – including snoods, caruncles (pebble-like bumps on the head and neck), skullcaps (thickened skin on the crown of the head), spurs (claws on the legs), and beards (tufts of hair-like feathers). protruding from the breast) – plays a role in the woman’s choice of partner. He found that the length of the snood was the main factor that explained which man a woman would choose as a mate. Even a few extra millimeters made a difference.
“It surprised me, especially since the snood doesn’t seem like a very functional choice,” said Dr. buchholz. “Why the neckerchief and not all the other ornaments on men?”
The answer lies in a phenomenon deeply rooted in biology: fancy endowments can indicate good genes. In turkeys, a male who can afford to wear a killer scarf must have had ample resources, supposedly reflecting the quality of his DNA. dr Buchholz found that males with longer snoods had fewer coccidia parasites, which do not harm adults but can sicken or kill chicks, and possess genes that may make them resistant to coccidia.
“Initially, it probably has a big impact on chick survival,” said Dr. buchholz. By choosing longer-snouted males, females can instill life-saving parasite resistance in their babies.
dr Buchholz isn’t sure yet about the role played by some of the other male jewels. Like snoods, other fleshy structures on a turkey’s face and neck may change color during display. For example, males will drain all of the blood from the caruncles, leaving them as white as a piece of paper, Dr. buchholz. He’s not sure what the change in caruncles might be signaling or why it’s important.
And what about those fancy feathers? “I don’t know if women care,” said Dr. buchholz. The feathers of male turkeys infected with coccidia reflect less of the ultraviolet light that turkeys (but not us humans) can see. However, no one has investigated whether females scoff at blunt feathers as much as they scoff at puny snoods.
There is still much to be learned about the mating behavior of wild turkeys. “For a bird that represents such a great conservation success story, that is so common and interesting to people, and that has a cultural connection to American Thanksgiving, it’s really a shame that we don’t know more about its behavior,” said dr Buchholz .
Maybe that’s not entirely surprising. Wild turkey populations are currently booming in many parts of the country thanks to conservation efforts; In places like New England, Madison, and Berkeley, they’re now so common that they get about as much attention from passing motorists as a traffic cone.
But that wasn’t always the case. Until recently, wild turkeys were rare in the United States — “which seems crazy now,” said Dr. Krakauer, “because they’re right in town and blocking traffic.”