Wild turkeys were once a prevalent species throughout the United States, with every state hosting a large and vibrant population. However, when European settlers arrived, indiscriminate killing, exploitation, and poisoning led to a dramatic decline in their numbers. By the 1900s, wild turkeys had disappeared from most areas where they once thrived. Thanks to regulation and conservation efforts, turkey populations were able to recover significantly. By the early 2000s, their numbers had nearly been restored to historical levels, but since then, progress has reversed.
A 2023 study found that wild turkey populations in the eastern United States are declining by 9% annually. While turkey numbers had increased in mid-Atlantic and Northwestern states, they still had not returned to their peak levels from the early 2000s. To understand why populations are declining, wildlife ecologists from various universities and institutions are studying existing populations and working to reintroduce turkeys to their original habitats.
Much of the woodland habitat in the U.S. has been destroyed and replaced by housing developments and other human activities. The remaining forests often lack the resources to support wild turkey populations. Turkeys need “a well-developed layer of vegetation at ground level that includes mainly wildflowers, native grasses, and young shrubs and trees” to provide nesting sites for laying eggs and raising their young, or poults, according to reports of the conversation. Habitat loss is one proposed reason for the population decline, though this explanation does not apply universally, as even areas with suitable nesting environments have experienced population reductions.
Prescribed burning of woodlands is another factor impacting turkey habitats. These burns force turkeys to seek forest areas with tall trees and sparse ground vegetation, which are less suitable for breeding.
Researchers in Wisconsin estimate that, to sustain their populations, turkey hens need to raise an average of 2.6 poults per hen. However, recent studies in Iowa found that turkey hens produce an average of only two poults per hen. To investigate further, researchers plan to capture hens from mid-January to late February of next year, equipping them with GPS devices and transmitters before releasing them back into the wild. Nesting season begins in April and peaks in late May, during which turkeys typically nest in areas with dense vegetation, which provides camouflage from predators.
Scientists aim to track 83 hens across multiple counties in Iowa, recording the dates, locations, and conditions of their nests. Hens typically lay one egg every one to one-and-a-half days, and eggs require about 30 days of incubation before hatching. Once the poults hatch, hens move to new locations to create fresh nests. This research will help identify the environmental conditions wild turkeys need to thrive.
Researchers also hope to study Lymphoproliferative Disease Virus (LPDV), a disease discovered in 2009 that is 100% fatal to turkeys and other birds. Iowa researchers plan to extract and analyze the virus to understand its mode of transmission and determine whether it can be passed from mothers to offspring. The spread of LPDV is another factor contributing to declining turkey populations. Studying it could provide valuable insights into genetic variables that affect animal populations.
Efforts like these aim to uncover the causes of the decline of the wild turkey population and inform strategies to help them recover and thrive once again.