Calling Citizen Scientists for Turkey Brood Surveys
The Illinois Department of Natural Resources (IDNR) uses many sources of data to manage the state’s wild turkey flock. Harvest totals, permit sales, hunter effort, and estimates of available habitat all play a role in determining the population trends of this popular game bird. Most of these data are obtained from hunters participating in the Spring Wild Turkey Hunting Season. One piece of important information is reproductive success. The primary source for reproduction data comes from the IDNR annual Wild Turkey Brood Survey which is conducted during June, July and August.
Monitoring trends in reproductive success is the best way of keeping track of how many new turkeys are added to the population each year. The wild turkey breeding season begins in late winter to early spring and continues through the end of May. Most hens begin laying eggs in mid-April and will lay about one egg per day until a full clutch of 12 to 14 eggs are laid. Once the nest is full of eggs, the hen will incubate nearly around the clock for 28 days straight, only getting up a few times each day. A brood of young turkeys, or poults, literally hit the ground running. Their day is spent attempting to eat as many insects as their small bellies can handle until they are able to fly at the age of two weeks. The first few months of a turkey’s life are critical as poults are highly susceptible to predation and cold, wet weather. The Brood Survey provides IDNR with a useful estimate of reproduction and survival of young turkeys.
The primary metric monitored is the ratio of poults to hens (poult:hen). However, many other data points are collected and monitored as well, including the proportion of hens with a brood, poults per brood, total number of adult hens, adult males, and poults, sex ratios, and total number of turkeys counted. Participants in turkey brood survey begin documenting turkey observations in June and continue through the end of August. Each observer is asked to document every turkey they see. Observers are provided with post cards to help organize the observations by date as well as the ages of observed turkeys.
The Illinois poult:hen ratio has certainly fluctuated over the last few decades according to IDNR records, however, there have been precipitous declines particularly in the last five years. The phenomenon of declining reproduction is not unique to Illinois. Across much of the nation, wildlife managers are noticing fewer young turkeys on the landscape and possibly fewer turkeys overall. It is unclear at this time what the primary causes of these declines might be. It is likely that several factors are playing a role, including changes in quality and quantity of habitat, rises in mesopredator (such as raccoon, skunks and opossums) populations, declines in insect populations, and perhaps even poorly timed hunting seasons.
Illinois is participating in a nationwide data sharing project to identify trends on a state, regional and national basis. This year will mark the third year of Illinois’ participation in the collaborative project. Currently there are 30-plus states contributing data to the effort. Regional similarities seem apparent based on preliminary data. Illinois appears to be in the same boat as other Midwestern states in experiencing declines in reproductive success. Several southeastern and Appalachian states are also observing declines, while some Great Plains and northeastern states share data indicating that turkey populations are relatively stable.
IDNR employees and other natural resource professionals from all over the state contribute to the survey. However, a large portion of these data come from public volunteers conducting citizen science. Contributors exist for nearly every county in the state, but some areas are better represented than others. IDNR can use additional participants. If you are interested in taking part in Illinois’ wild turkey management effort, please let the IDNR know! Ideal candidates for the Wild Turkey Brood Survey regularly drive through or work in rural areas with wild turkey habitat.
If you are interested in participating in the survey, send an email to DNR.Wildliferecep@Illinois.gov with TURKEY BROOD SURVEY as the subject, also providing your name and mailing address. You will be sent a survey packet with postcards on which to record turkey sightings as well as instructions on how to fill out and submit the cards.
All contributions to this important project are appreciated.
Luke Garver is the Wild Turkey Project Manager with the Illinois Department of Natural Resources, Division of Wildlife Resources.