For many people, seeing a wild turkey in the Lehigh Valley is an exciting or noteworthy occurrence. Unlike deer, squirrels, rabbits and other common game animals, the birds aren’t distributed evenly across the local landscape. In fact, in some areas, they are quite rare or even nonexistent.
Well, if you happen to see any of the birds this summer, the Pennsylvania Game Commission is encouraging you to report the sighting to assist it with its turkey management research. From now through Aug. 31, individuals can go online here to record the number of birds they see, along with the location on the sighting, date and their contact information. Although the PGC wants to know about all the birds on the landscape, it’s especially interested in hens and their young of the year, known as broods, to help it get a handle on turkey survival and productivity rates.
This citizen-scientist survey, started in 2016, helps the PGC track population trends and compare long-term reproductive success within Pennsylvania and across states. The survey bolsters the data provided by the agency’s internal survey, which has been conducted by state game wardens since the 1960s.
“Really, what it does is it increases the sample size tremendously so it gives us more confidence in the data,” said PGC Wild Turkey Biologist Mary Jo Casalena. “So, when we statistically analyze (the data), the levels are real tight and we can use the data with more certainty in our turkey population models.
“The sighting survey is (done) to give us an indication of the turkey productivity, the summer reproduction. It’s the number of poults sighted per all hens sighted. It includes not only the successful hens but also the barren hens — the hens that didn’t produce. But that’s what we are interested in; we’re interested in total reproduction.”
Over the past decade or so, Pennsylvania’s statewide turkey population has declined overall, and biologists are trying to get a handle on why the drop has occurred. Factors like cold or rainy weather during the spring nesting season, habitat quality, predation and hunter harvest during the fall turkey seasons all have an impact on turkey productivity. That said, some areas of the state, such as the southwestern and northwestern parts of the state have populations that are doing quite well, while in other areas, such as the northeastern and northcentral regions, the birds are below population goals. Overall, according to the PGC, turkey populations are below average in 15 of the state’s 23 Wildlife Management Units (WMU).
As for reproductive success, Casalena said the statewide average is typically 2.7 or 2.8 poults per hen. In 2021, that figure was above average, with 3.1 poults per hen statewide, resulting in better-than-average turkey survival heading into this year’s spring breeding season. One of the reasons for the overall good reproduction last year was the cicada hatch.
“Most of the Wildlife Management Units in the southern tier, where we had cicada hatches, had above average reproduction,” Casalena said, “but some of our northern units had below-average reproduction.”
As Pennsylvania’s turkey population has declined, one of the ways the PGC has tried to ease pressure on the birds is by making changes to the fall turkey-hunting seasons, including shortening season dates, eliminating the use of rifles starting with the 2021 season and other tweaks. The agency has also embarked on a pair of four-year studies to try and gain a better understanding of how the birds are impacted by and interact with their environment and different environmental factors. The studies, which are being done concurrently, are taking place in four Wildlife Management Units that represent a diverse array of turkey densities and habitat. Included are local WMU 5C, which has the lowest overall turkey population densities and hunter harvest numbers in the state — primarily due to the high human population and the fact that quality turkey habitat is so fragmented — as well as WMU 2D in the northwestern part of the state, where some of the best turkey habitat and populations are currently found. The other two WMUs are 3D in the Poconos and 4D in the central part of the state.
“In a nutshell, we’re trying to get a better handle on turkey population dynamics as a whole,” Casalena said. “We’re looking at different environmental factors that interact (with the birds) and we’re trying to determine why turkey populations in some management units are doing really well, while in other wildlife management units they are not doing well.”
As part of the study, the PGC and Penn State University are trapping more than 100 birds each winter in the four participating WMUs. Hens are then fitted with GPS transmitters, allowing researchers to monitor their movement across the landscape in greater detail.
“We’re looking at survival (and) reproduction, but these transmitters also tell us about turkey activity,” she said. “So, we’ll be able to tell what kind of habitat (a hen) is in and what it’s doing in that habitat. We’ll know if it’s feeding, if it’s resting, if it’s moving in each of these different habitats.
“It’s going to give us a much better idea of how they are moving through the landscape, where they are spending their time and what they’re doing, and we are going to be able to compare that among the different habitat types.”
The second study, done in conjunction with veterinarians from University of Pennsylvania School of Veterinary Medicine’s Wildlife Futures Program, involves drawing blood samples from the hens when they are trapped. The goal is to look for diseases and how disease might be impacting turkey survival and reproductive success. Right now, Casalena said, the impact of disease on wild turkeys in the state is still a big ‘unknown.’
“In Pennsylvania, we’ve never studied disease like this for turkeys,” she said. “We know from our passive surveillance of turkeys … that there are some new diseases that have popped up and we don’t know how that might be impacting productivity.”
