Data and code from: Retroviral infections affect survival and clutch size of female wild turkeys

Pathogens can regulate or decimate free-ranging wildlife populations. Wild
turkeys (Meleagris gallopavo), which are widespread across the United
States, southern Canada, and northern and central Mexico, are a prized
upland gamebird that has experienced dramatic population growth and range
expansion as the result of reintroduction campaigns. While increased
abundance may promote disease transmission, little is known about the
effects of pathogen infections on demographic metrics in wild turkeys.
Lymphoproliferative disease virus (LPDV) and reticuloendotheliosis virus
(REV) are oncogenic retroviruses that infect poultry and wild turkeys and
can result in disease and mortality, though most infected individuals
appear asymptomatic. We investigated whether retroviral infections
influence wild turkey fitness by evaluating effects on female survival and
several reproduction metrics. We live-captured 163 female wild turkeys
throughout central Maine, USA, during three winters, from 2018–2020. We
collected blood for LPDV and REV molecular diagnostics and attached a GPS
or VHF transmitter to monitor survival and nesting. Infection with REV was
associated with nearly half the cumulative annual survival probability,
while LPDV-infected hens laid an average of 1.4 fewer eggs per clutch. We
detected no effects of retroviral infection on nest initiation, nesting
propensity, or hatch rate, and coinfection was not associated with any
measured demographic metric. These findings demonstrate that retroviral
infections can negatively affect survival and clutch size in female wild
turkeys even in the absence of overt disease, highlighting the importance
of considering pathogen effects when evaluating the population dynamics of
free-ranging wildlife.