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For wide-ranging species in temperate environments, populations at high-latitude range limits are subject to more extreme conditions, colder temperatures, and greater snow accumulation compared with their core range. As climate change progresses, these bounding pressures may become more moderate on average, while extreme weather occurs more frequently. Individuals can mitigate temporarily extreme conditions by changing daily activity budgets and exhibiting plasticity in resource selection, both of which facilitate existence at and expansion of high-latitude range boundaries. However, relatively little work has explored how animals moderate movement and vary resource selection with changing weather, and a general framework for such investigations is lacking. We applied hidden Markov models and step selection functions to GPS data from wintering wild turkeys (Meleagris gallopavo) near their northern range limit to identify how weather influenced transition among discrete movement states, as well as state-specific resource selection. We found that turkeys were more likely to spend time in a stationary state as wind chill temperatures decreased and snow depth increased. Both stationary and roosting turkeys selected conifer forests and avoided land covers associated with foraging, such as agriculture and residential areas, while shifting their strength of selection for these features during poor weather. In contrast, mobile turkeys showed relatively weak resource selection, with less response in selection coefficients during poor weather. Our findings illustrate that behavioral plasticity in response to weather was context dependent, but movement behaviors most associated with poor weather were also those in which resource selection was most plastic. Given our results, the potential for wild turkey range expansion will partly be determined by the availability of habitat that allows them to withstand periodic inclement weather. Combining hidden Markov models with step selection functions is broadly applicable for evaluating plasticity in animal behavior and dynamic resource selection in response to changing weather. We studied turkeys at northern range limits, but this approach is applicable for any system expected to experience significant changes in the coming decade, and may be particularly relevant to populations existing at range peripheries., (© 2022 The Ecological Society of America.)

The monitoring of infectious diseases in wildlife is crucial for assessing animal health, pathogen range expansion, and the risk of spillover to naive species, but may be resource and labor intensive. Lymphoproliferative disease virus (LPDV) is an avian oncogenic retrovirus that was first identified in wild turkeys (Meleagris gallopavo) in 2009, though it historically caused mortality in domestic turkeys in Europe and Israel. Subsequent surveys detected a high prevalence and broad distribution throughout the eastern United States, warranting further research on LPDV in wild turkey populations. Current LPDV diagnostics require the collection of tissues, such as bone marrow from dead birds or blood during live capture. In our study, we assessed the sensitivity (true positive) and specificity (true negative) of cloacal swab samples as an alternative LPDV detection method. We compared results from cloacal swab samples with both postmortem detection from bone marrow and antemortem detection from blood, using a multi‐tube PCR approach with 3 replicates. Swab samples collected from live‐captured turkeys had a greater sensitivity (88%) than swabs collected from hunter‐harvested turkeys (31%), whereas specificity was similar for both collection approaches (live‐capture swabs = 75%, n = 85; hunter‐harvest swabs = 80%, n = 54). In live‐captured turkeys, the estimated LPDV prevalence using cloacal swab samples (73%) was not significantly different from the true prevalence determined using coupled blood samples (76%). However, in hunter‐harvested turkeys, the estimated prevalence using cloacal swab samples (28%) was different from the true prevalence estimated using coupled bone marrow samples (72%). In summary, cloacal swab samples can be used to reliably detect LPDV infection in live‐captured wild turkeys but should not be used for LPDV detection in hunter‐harvested wild turkeys. [ABSTRACT FROM AUTHOR]

Limiting the potential for disturbance of wild turkey (Meleagris gallopavo) breeding and nesting is often stated as a concern for management, particularly when associated with the spring hunting season. The timing of wild turkey nesting has been shown to vary with latitude, with spring phenology, and among individuals, but local information on nesting timing is needed to fully evaluate local harvest regulations. Our objectives were to characterize wild turkey nesting phenology and identify overlap with current hunting season timing and hunter effort in Maine, USA. We also identified sources of variation related to land cover and individual female characteristics such as body condition and pathogen infection status. Finally, we compared the temporal distributions of nest initiation across the 2 years of our study. We assessed nesting phenology of eastern wild turkeys (M. g. silvestris) in Penobscot, Hancock, and Cumberland counties, Maine, by monitoring females for nesting activity using VHF and GPS transmitters. During April–July 2018 and 2019, we located 69 nests from radiomarked females and 3 nests from unmarked females. Of the nests discovered, 56 were presumed first attempts, 12 were second attempts, and one was a third attempt. The median date of nest initiation (i.e., date first egg was laid) for first nests was April 27 in 2018 and May 5 in 2019. Females that nested in areas with greater residential and urban development initiated nests earlier than females that used more rural agricultural land covers. Despite a delay in the onset of nesting in 2019, the distribution of nest initiation among females did not change throughout the season. Our results indicate that the majority of male harvest occurred concurrently with egg laying. Thus, current hunting season timing likely limits risks associated with disturbance of mating. Given that Maine's wild turkey population is thought to be stable or increasing, our data support maintaining the current hunting season structure. However, breeding and nesting phenology of wild turkeys should continue to be monitored in relation to changing environmental conditions, trends in the turkey population, hunter numbers, and spring harvest, so that future changes can be incorporated into harvest management and decision making. [ABSTRACT FROM AUTHOR]