Wild Side : Turkeys, once native on Martha's Vineyard, star tomorrow
Photo by Matt Pelikan
Three cheers — well, two cheers, anyway — for the bird of the hour: Meleagris gallapavo, known to its friends as the turkey.
I don't say "wild turkey," because when it comes to the population that is resident on Martha's Vineyard, "wild" doesn't quite fit. Our turkeys are best thought of as a feral population, joining a short list of other species that occupy a shady area between domestic animals and truly wild ones. Like pheasants, bobwhite quail, mute swans, our nonmigratory Canada geese, and our elusive population of freelance kitties, our turkeys reflect a history of replenishment by humans from captive stock. Superficially resembling their truly wild counterparts, and more or less able to sustain a population on their own, all of these animals differ physically from truly wild ancestral populations, and in their behavior, they reflect a history of familiarity with the human species.
The Island had well-documented aboriginal populations of several chicken-like birds, but being desirable prey and vulnerable to nest predation by skunks and raccoons, these have not fared well over the years. Though bobwhites have always occurred on the Island, our distinctively large and pale native population has disappeared, its genes overwhelmed through breeding with waves of introduced quail. The ruffed grouse, once reasonably common in our woodlands, no doubt suffered from deforestation following the arrival of Europeans, failed to recover along with the regrowing forests, and now appears to be gone. And, famously, the heath hen, technically the eastern subspecies of the greater prairie-chicken, went extinct on the Vineyard and in the universe in 1932.
The history of our turkeys is a bit more obscure. They must have been here originally: fond of acorns and especially beech nuts, turkeys would have flourished among the woodland types that have prevailed here since before rising sea levels isolated us as an Island. But the species as a whole was extirpated in Massachusetts by the middle of the 19th century, a victim of over-hunting and, perhaps, habitat alteration. On the Vineyard, it was apparently gone long before that, and I'm not even sure turkeys persisted long enough to be eaten by the first European settlers.
By the mid-20th century, reforestation of land previously cleared for farming had created large tracts of suitable turkey habitat, and an aggressive campaign of reintroduction began. Seeking to reestablish a sought-after game bird, state biologists introduced captured wild birds from populations in Pennsylvania and, I have read, from as far away as the southwestern U.S. Several introductions on nearby Naushon Island failed to take hold, despite vast tracts of the turkey's favored American beech. According to information provided by the state, though, no formal reintroduction of turkeys ever took place on the Vineyard.
Our birds, then, probably descend from accidental or at least amateur releases of pen-raised birds, probably reflecting a mixture of wild stocks that had been at least somewhat altered by human husbandry. Occasional piebald "wild" turkeys reflect either this checkered origin or subsequent interbreeding with white farm-yard turkeys. Our population appears stable but is not large, in the scores or at most hundreds. Reflecting its origins, it concentrates in the more settled portions of the Vineyard: this is one species you're more likely to encounter on the outskirts of Vineyard Haven than in a tract of up-Island woodland. "Wild" in the sense of reproducing successfully with no deliberate human intervention, our turkeys are far more accepting of humans than truly wild birds would be.
Unlike some feral or introduced species, our turkeys don't seem to have any undesirable ecological impacts. Their numbers remain in check, between road-kill mortality, light hunting pressure, and predation of eggs and chicks by skunks, hawks, and probably great horned owls (which remain scarce but appear to be here to stay). Unlike mute swans, which compete aggressively for nesting space against native waterfowl, turkeys don't seem to pose a challenge to other birds. And while as a source of food for skunks and raccoons, turkeys arguably encourage species that most wildlife experts consider excessively numerous on the Vineyard; on the other hand, by offering another source of prey, turkeys may actually take predatory pressure off other ground-nesting birds.
No, it is in its interactions with its prime benefactor that the turkey becomes a problem. By nature territorial and aggressive in defense of breeding and feeding sites, our feral turkeys are also complacent — too complacent — around people. Even a full-grown tom turkey can do only limited damage to an adult human. But these are powerful birds, with an innate urge to be intimidating. (My favorite turkey story involves a set of renters in a cabin on Lake Tashmoo who were kept virtually captive for their whole vacation by a flock of aggressive turkeys.)
So on Thanksgiving, as you wait for one of their fully domesticated brothers to finish browning, reflect for a moment on our feral turkeys: on odd case where the human side and the Wild Side overlap.