Wild turkeys face an uncertain future

Wild turkey male, or “tom” (Photo provided by Cornell Lab of Ornithology)

The wild turkey, Meleagris gallopavo, is one of only two domesticated birds native to North America. The Muscovy duck is the other. Five sub-species make up the entire North American population.

The most abundant is the eastern wild turkey — sub-species silvestris, meaning forest — which ranges across the entire eastern half of the United States and parts of eastern Canada. They’re readily identified by their brown-tipped tail feathers, which spread into a fan when the birds are courting or alarmed, and by the bold black and white bar pattern displayed on their wing feathers. This is the same turkey variety encountered by the pilgrims.

According to Cornell University’s Lab of Ornithology, wild turkeys have a global breeding population estimated to be 7.8 million birds, with 89 percent of them living in the U.S. Including their eggs, they are considered an ecologically important part of the food chain, providing nourishment to a wide variety of predators: e.g. foxes, coyotes, weasels, snakes, hawks and owls. When threatened, females (hens) tend to fly. Males (toms) tend to run. When they need to, turkeys can swim.

Humans represent the wild turkeys’ most aggressive predator and greatest threat. During the 19th century, indiscriminate hunting and systematic eradication of forests and wetlands resulted in wild turkeys being driven to near-extinction across almost all of their North American range.

Throughout the first half of the 20th century, wildlife biologists tried restoring wild turkey populations by releasing pen-raised birds into the wild. Their efforts were unsuccessful. Then, in 1951, they devised a method for trapping and relocating small flocks of wild turkeys using huge nets fired from cannons. The relocated flocks flourished and their range began to expand.

Wild turkeys are now found and hunted in 49 states. They live, but are not hunted, in Hawaii. American sportsmen and women harvest roughly 700,000 turkeys annually, making them the most sought after game bird on the continent. The U.S. Fish and Wildlife Service estimates that 21 percent of all U.S. hunters (about 2.5 million people) pursue turkeys, making them the nation’s second-most hunted game animal. (Deer are the first.) And wildlife biologists, veterinarians and pathologists who have studied wild turkeys view managed spring and fall hunting as a way to limit the spread of parasites and diseases.

While parasites and diseases have rarely had serious impacts on turkey populations, there are several maladies that do kill individual birds, either directly or by leaving them more susceptible to predation. Avian pox is one such disease. It’s transmitted among wild turkeys by biting insects, mosquitoes primarily. It rarely causes death.

Histomoniasis, more commonly known as blackhead, is another. The disease organism lives in the digestive tract of small roundworms and is passed when healthy birds eat the droppings of infected birds or eat earthworms that have fed on the droppings. Because domestic poultry are often resistant to blackhead, wild turkeys are more likely to pick up the disease from domestic poultry than the other way around. Wild turkeys have never been linked to disease outbreaks in domestic poultry, cattle, people or pets.

Wild turkey numbers in New York state have been in decline since 2007. And research by Cornell University’s College of Veterinary Medicine, SUNY’s College of Environmental Science and Forestry, and the state Department of Environmental Conservation indicates that one reason for this may be lymphoproliferative disease virus (LPDV), which can cause tumors to form in the spleen and liver of infected young turkeys. Monitoring for LPDV is currently underway, statewide, by the Cornell Wildlife Health Lab, in partnership with the DEC.

LPDV has been found in wild turkeys in 17 states, with hunter-harvested birds testing positive for the virus in every county in New York. In fact, more than half of the birds tested in New York were shown to be carrying the virus. And 81 percent of tested females were infected. Surprisingly, most of the affected birds appeared to be perfectly healthy.

It’s unclear how a population can support such a high occurrence of the LPDV pathogen. And prior studies in domestic birds have suggested that the virus may be able to infect other birds in the order Galliformes: e.g. ring-necked pheasant and spruce grouse (Ianconescu 1983).

Keeping domestic birds and contaminated feed away from wild birds significantly reduces the potential for extensive impact from diseases. Some people attract turkeys to their yards by scattering birdseed or corn on their lawns. Be aware that this can also attract rodents. If you have a large yard near a woods, you can attract wild turkeys by planting fruit or nut-bearing trees and shrubs.

Landowners and managers can make providing quality habitat a part of their management plan. You can learn more at www.dec.ny.gov/animals/7288.htm.