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Hailstorms capable of producing damaging hail ≥2.5 cm in size are rare but can have a significant impact on wildlife, with mortality events well documented with avian species. However, there is still a poor understanding of the impacts damaging hail can have on ungulate survival. We had a unique case study, when a hailstorm produced hailstones up to ∼7 cm in diameter in the area of Camp Hill, AL, and the nearby Auburn Captive Deer Facility (ACF) on 26 March 2023. With the ACF being completely enclosed with fencing, we were able to conduct extensive surveys for mortality cases of Odocoileus virginianus (White-tailed Deer) shortly after the hailstorm. We detected no cases of mortality attributed to the storm. We speculate that no mortality occurred due to the ACF containing mature forests with adequate overstory that provided structural cover for deer from hailstone strikes. Further examination of the literature found that a substantial proportion of hail-induced mortality has occurred in agricultural areas, wetlands, and grasslands where there was limited to no canopy cover. This result may suggest that deer inhabiting forested regions are at less risk from hailstorms compared to conspecifics inhabiting open habitat. [ABSTRACT FROM AUTHOR]

Based on principles of natural selection, high-quality individuals may benefit by selecting mates of similar phenotypic quality when given the opportunity; that is, individuals may benefit by engaging in a form of non-random mating referred to as positive assortative mating. In ungulates, the idea of mate selectivity is still highly debated, with few studies providing evidence of positive assortative mating. In white-tailed deer (Odocoileus virginianus), recent studies have suggested minimal mate selectivity based on phenotypic characteristics. However, findings from these previous studies may be due to the fact that study populations had young age structures and female skewed sex-ratios that may have limited opportunities for preferential mating. From 2008 to 2019 we studied a captive population of white-tailed deer to examine characteristics of 184 parental pairs that successfully recruited fawns, while the population underwent changes in age structure and sex ratio, and we found evidence of non-random mating in parental pairs. Specifically, for each 1-year increase in male age there was a 0.32-year increase in female age among parental pairs, and for every 1.00 cm increase in male skeletal body size there was a 0.18 cm increase in female skeletal body size. We also observed that as the male and female age structures increased over time, the slope of the relationship between male and female lifetime body percentiles of parental pairs had a greater positive increase over time. Furthermore, we observed that breeding success by younger males decreased as the age structure matured. Although, even with evidence for non-random mating, we were unable to firmly conclude these findings as assortative mating due to the fact we still observed cases where there was a large difference in age between mates, indicating some plasticity with mating. Overall, our results suggest that individuals of an older age and greater body size may select for individuals of a similar condition if provided with the opportunity. However, choosiness appears dynamic, with a decrease in selectivity when preferential mates are limited due to a young age structure or when mating opportunities decrease for poor competitors in a population with a mature age structure. [ABSTRACT FROM AUTHOR]

As scatterhoarders, Sciurus carolinensis (Eastern Gray Squirrel) usually rely on food they buried during fall to survive cold winter months. However, the range of this species includes areas of the southeastern United States where winter flooding commonly restricts access to buried food during the recovery season. In this study, we investigated the effects of winter flooding on the diet of Eastern Gray Squirrels in bottomland hardwood forests of west-central Alabama. We examined the diet of 42 Eastern Gray Squirrels through DNA analysis of stomach contents collected during fall (September–November) 2016 and winter (December–February) 2015–2016, 2016–2017, and 2018–2019. Eastern Gray Squirrels ate 21 different types of plants, with 6 principal foods (>1% of any squirrel's stomach contents) during fall and 12 principal foods during winter. Throughout both seasons, Juglandaceae (walnut) and Quercus spp. (oak) were the most important foods and together made up 94.1% of the fall diet and an average of 78.6% of the winter diet. In contrast to other studies, we found more varied diets during winter (12 primary foods eaten) than fall (6). Additionally, a majority of the plant types consumed during winter at our study area were not hard-mast plants, and many had not been previously recorded as part of the diet of the Eastern Gray Squirrel. Our results suggest Eastern Gray Squirrels cope with reduced availability of scatterhoarded food due to winter flooding by increasing the diversity of foods they eat to include more herbaceous plants. [ABSTRACT FROM AUTHOR]

Wild pigs (Sus scrofa) are among the most detrimental invasive species in the USA. They are damaging to crops and agriculture, pose a public health risk as reservoirs of zoonotic pathogens, and may also spread disease to livestock. One pathogen identified in wild pigs is bovine viral diarrhea virus (BVDV), a virus that causes an economically important disease of cattle (Bos taurus and Bos indicus). We sought to determine the BVDV seroprevalence in wild pigs in 17 states across the US and to determine whether age category, sex, or location were associated with a positive antibody titer. Serum samples from 945 wild pigs were collected from 17 US states. Virus neutralization assays were performed to determine antibody titers against BVDV-1b and BVDV-2a. Total BVDV seroprevalence for the study area was 5.8% (95% confidence interval [CI], 4.11-8.89). Seroprevalence across all evaluated states was determined to be 4.4% (95% CI, 2.48-6.82) for BVDV-1b and 3.6% (95% CI, 1.54-5.60) for BVDV-2a. The seroprevalence for individual states varied from 0% to 16.7%. There was no statistical difference in median antibody titer for BVDV-1b or BVDV-2a by sex or age category. State seroprevalences for both BVDV-1b and BVDV-2a were associated with wild pig population estimates for those states., (© Wildlife Disease Association 2024.)

Functional responses describe how changing resource availability affects consumer resource use, thus providing a mechanistic approach to prediction of the invasibility and potential damage of invasive alien species (IAS). However, functional responses can be context dependent, varying with resource characteristics and availability, consumer attributes, and environmental variables. Identifying context dependencies can allow invasion and damage risk to be predicted across different ecoregions. Understanding how ecological factors shape the functional response in agro-ecosystems can improve predictions of hotspots of highest impact and inform strategies to mitigate damage across locations with varying crop types and availability. We linked heterogeneous movement data across different agro-ecosystems to predict ecologically driven variability in the functional responses. We applied our approach to wild pigs (Sus scrofa), one of the most successful and detrimental IAS worldwide where agricultural resource depredation is an important driver of spread and establishment. We used continental-scale movement data within agro-ecosystems to quantify the functional response of agricultural resources relative to availability of crops and natural forage. We hypothesized that wild pigs would selectively use crops more often when natural forage resources were low. We also examined how individual attributes such as sex, crop type, and resource stimulus such as distance to crops altered the magnitude of the functional response. There was a strong agricultural functional response where crop use was an accelerating function of crop availability at low density (Type III) and was highly context dependent. As hypothesized, there was a reduced response of crop use with increasing crop availability when non-agricultural resources were more available, emphasizing that crop damage levels are likely to be highly heterogeneous depending on surrounding natural resources and temporal availability of crops. We found significant effects of crop type and sex, with males spending 20% more time and visiting crops 58% more often than females, and both sexes showing different functional responses depending on crop type. Our application demonstrates how commonly collected animal movement data can be used to understand context dependencies in resource use to improve our understanding of pest foraging behavior, with implications for prioritizing spatiotemporal hotspots of potential economic loss in agro-ecosystems., (© 2019 by the Ecological Society of America.)

Cattle persistently infected (PI) with bovine viral diarrhea virus (BVDV), a pestivirus in the family Flaviviridae, are an important source of viral transmission to susceptible hosts. Persistent BVDV infections have been identified in white-tailed deer (Odocoileus virginianus), the most abundant free-ranging ruminant in North America. As PI deer shed BVDV similarly to PI cattle, maintenance of BVDV within white-tailed deer populations may be possible. To date, intraspecific transmission of BVDV in white-tailed deer has not been evaluated, which prompted this study. Six pregnant white-tailed deer were captured in the first trimester of pregnancy and cohabitated with a PI white-tailed deer. Cohabitation with the PI deer resulted in BVDV infection in all does, as indicated by seroconversion. All does gave birth to live fawns and no reproductive losses were observed. At birth, evidence of BVDV infection was identified in two singlet fawns, of which one was determined to be PI by repeated serum reverse transcription nested PCR, whole blood virus isolation and immunohistochemistry. This study demonstrates for the first time that BVDV transmission may occur among white-tailed deer. The birth of a PI fawn through contact to a PI white-tailed deer indicates that under appropriate circumstances, BVDV may be maintained in white-tailed deer by congenital infection., (INRA, EDP Sciences, 2009)