Behavior of Wild Pigs toward Conspecific Carcasses: Implications for Disease Transmission in a Hot, Semiarid Climate

Wild pigs (Sus scrofa) are a prolific, invasive species in the United States of America and act as vectors for many pathogens. An emerging pathogen of concern to the USA is African swine fever (ASF), a deadly viral disease affecting swine that is endemic to Africa and has spread to parts of Europe, Asia, and the Caribbean. ASF affects both wild and domesticated pigs and can be transmitted via several avenues, including interactions between and consumption of dead pigs by their live conspecifics. As wild pigs are considered a serious threat in the transmission of ASF, understanding the behavior of wild pigs towards their dead conspecifics is imperative when considering the transmission of ASF and other diseases in the USA. We placed camera traps at a sample of wild pig carcasses dispatched during four aerial shooting events between November, 2020, and June, 2022, at East Foundation’s San Antonio Viejo Ranch, South Texas. We recorded visitation events to carcasses by live wild pigs and recorded their behavior. Furthermore, we assessed daily carcass decomposition rates by visiting carcass sites without cameras. We found no evidence of cannibalism and recorded live wild pig visitations to only 33% of carcasses before advanced stages of decomposition were reached. Carcass decomposition was rapid (2.5 to 3 days), regardless of season, and the time to the first visitation and investigation of carcasses by live conspecifics was quicker than has been recorded in Europe. We posit that active scavenger guilds at our study site, coupled with high temperatures, result in the rapid decomposition of wild pig carcasses, which reduces opportunities for live wild pigs to interact with them when compared to milder climates. We suggest additional research investigating the persistence of ASF in hot, arid climates and the interactions between live pigs and the skeletonized remains of conspecifics

The influence of income and loss on hunters\u27 attitudes towards wild pigs and their management

Wild pigs (Sus scrofa) are one of the most pervasive invasive species in North America. Wild pigs pose a threat to crops, livestock, and the environment, but also provide recreational hunting opportunities. There are avenues for some stakeholder groups to generate income from wild pigs, however, stakeholders vary in attitudes towards wild pigs and their management. We investigated whether financial loss and income resulting from wild pigs influenced hunter stakeholder attitudes towards their management in Texas. We examined how land use influenced hunting landowner attitudes towards wild pigs. We analyzed 22,176 responses (8,707 landowners, 13,469 nonlandowners) fromTexas hunters to theTexas A&M Human Dimensions of Wild Pigs Survey. Attitudes towards wild pigs varied significantly based on landownership status and whether land was used for agricultural practices. In addition, landowners who received income from wild pigs on their land considered government or agency hunting to be a less acceptable method of control than those who did not generate such income. However, effect sizes for all our results were small (η2 ≤ 0.05, Adj. R2 ≤ 0.09, and McFadden\u27s R2 ≤ 0.07) and, across all groups, attitudes towards wild pigs were negative. Few respondents (3.91% of landowners, 0.56% of non‐landowners) reported generating income from wild pigs, and reported losses were approximately 4 times greater than income. Supplemental file attached

Men's Sexual Faithfulness Judgments May Contain a Kernel of Truth.

Mechanisms enabling men to identify women likely to engage in extra-pair copulations (EPCs) would be advantageous in avoiding cuckoldry. Men's judgments of female sexual faithfulness often show high consensus, but accuracy appears poor. We examined whether accuracy of these judgments made to images of women could be improved through i) employing a forced choice task, in which men were asked to select the more faithful of two women and/or ii) providing men with full person images. In Experiment 1, men rated 34 women, for whom we had self-reported EPC behavior, on faithfulness, trustworthiness or attractiveness from either face or full person photographs. They then completed a forced choice task, selecting the more faithful of two woman from 17 pairs of images, each containing one woman who had reported no EPCs and one who had reported two or more EPCs. Men were unable to rate faithfulness with any accuracy, replicating previous findings. However, when asked to choose the more faithful of two women, they performed significantly above chance, although the ability to judge faithfulness at above-chance levels did not generalize to all pairs of women. Although there was no significant difference in accuracy for face and full person image pairs, only judgments from faces were significantly above chance. In Experiment 2, we showed that this accuracy for faces was repeatable in a new sample of men. We also showed that individual variation in accuracy was unrelated to variation in preferences for faithfulness in a long-term partner. Overall, these results show that men's judgments of faithfulness made from faces of unfamiliar women may contain a kernel of truth

Sperm Competition in Humans: Mate Guarding Behavior Negatively Correlates with Ejaculate Quality

<div><p>In species where females mate with multiple males, the sperm from these males must compete to fertilise available ova. Sexual selection from sperm competition is expected to favor opposing adaptations in males that function either in the avoidance of sperm competition (by guarding females from rival males) or in the engagement in sperm competition (by increased expenditure on the ejaculate). The extent to which males may adjust the relative use of these opposing tactics has been relatively neglected. Where males can successfully avoid sperm competition from rivals, one might expect a decrease in their expenditure on tactics for the engagement in sperm competition and vice versa. In this study, we examine the relationship between mate guarding and ejaculate quality using humans as an empirical model. We found that men who performed fewer mate guarding behaviors produced higher quality ejaculates, having a greater concentration of sperm, a higher percentage of motile sperm and sperm that swam faster and less erratically. These effects were found independent of lifestyle factors or factors related to male quality. Our findings suggest that male expenditure on mate guarding and on the ejaculate may represent alternative routes to paternity assurance in humans.</p></div

Faithfulness accuracy (proportion of trials in which the faithful model was correctly chosen in a forced choice task) in Experiment 1 and Experiment 2.

<p>The x-axis represents chance level (0.5) and S.E bars are shown.</p

Relationship between mate guarding frequency and PC1 (after accounting for the influence of lifestyle and collection variables), which describes ejaculates with a high percentage of motile sperm and high swimming speed.

<p>Relationship between mate guarding frequency and PC1 (after accounting for the influence of lifestyle and collection variables), which describes ejaculates with a high percentage of motile sperm and high swimming speed.</p

Relationship between mate guarding frequency and the unstandardized residuals of PC3 (after accounting for the influence of lifestyle and collection variables), which describes ejaculates with a high concentration of sperm and sperm that do not move erratically.

<p>Relationship between mate guarding frequency and the unstandardized residuals of PC3 (after accounting for the influence of lifestyle and collection variables), which describes ejaculates with a high concentration of sperm and sperm that do not move erratically.</p

Principal components analysis on all sperm quality parameters to produce principal components that account for sperm quality.

<p>VAP =  average path velocity, VSL =  straight line velocity, VCL =  velocity along the sperm cells point-to-point track, ALH =  lateral amplitude of sperm head movement, BCF =  frequency with which the sperm head crosses the average sperm path, STR =  straightness of the sperm's path, LIN =  linearity of the sperm's path, % motile =  percentage of motile sperm in the ejaculate, concentration =  concentration of sperm in the ejaculate (million sperm/ml).</p><p>Principal components analysis on all sperm quality parameters to produce principal components that account for sperm quality.</p

Winter habitats of bats in Texas

Few studies have described winter microclimate selection by bats in the southern United States. This is of particular importance as the cold-adapted fungus, Pseudogymnoascus destructans, which causes the fatal bat disease white-nose syndrome (WNS), continues to spread into southern United States. To better understand the suitability of winter bat habitats for the growth of P. destructans in this region, we collected roost temperature and vapor pressure deficit from 97 hibernacula in six ecoregions in Texas during winter 2016–17 and 2017–18. We also measured skin temperature of Rafinesque’s big-eared bats (Corynorhinus townsendii), Townsend’s big-eared bats (C. townsendii), big-brown bats (Eptesicus fuscus), southeastern myotis (Myotis austroriparius), cave myotis (M. velifer), tri-colored bats (Perimyotis subflavus), and Mexican free-tailed bats (Tadarida brasiliensis) during hibernation to study their use of torpor in these habitats. We found that temperatures within hibernacula were strongly correlated with external air temperatures and were often within the optimal range of temperatures for P. destructans growth. Hibernacula and skin temperatures differed among species, with Rafinesque’s big-eared bats, southeastern myotis, and Mexican free-tailed bats occupying warmer microclimates and having higher torpid skin temperatures. For species that were broadly distributed throughout Texas, hibernacula and skin temperatures differed within species by ecoregion; Tri-colored bats and cave myotis in colder, northern regions occupied colder microclimates within hibernacula and exhibited colder skin temperatures, than individuals of the same species in warmer, southern regions. These data illustrate the variability in microclimates used as hibernacula by bats in Texas and suggest similar variation in susceptibility to WNS in the state. Thus, monitoring microclimates at winter roosts may help predict where WNS may develop, and where management efforts would be most effective

Structural and environmental predictors of presence and abundance of tri-colored bats in Texas culverts

The tri-colored bat (Perimyotis subflavus) is being reviewed for listing under the Endangered Species Act by the United States Fish and Wildlife Service. It is also listed as a species of greatest conservation need by the Texas Parks and Wildlife Department due to its susceptibility to white-nose syndrome (WNS) in other states. Several colonies of hibernating tri-colored bats have been documented roosting in culverts. Culverts are widespread in Texas as part of roadway infrastructure; thus, our objective was to understand and quantify which structural and environmental factors best explain culvert use and abundance of hibernating tri-colored bats in Texas. We selected and surveyed 207 culverts for presence of tri-colored bats using the Generalized Random Tessellation Stratified (GRTS) design and opportunistic sampling across 10 of 12 Texas level III ecoregions during the winters of 2016–2017 and 2017–2018. We recorded environmental and structural features of culverts at each site. We used a zero-inflated Poisson regression to identify which culvert features best explained presence and abundance of hibernating tri-colored bats. We found that number of culvert sections predicted presence of tri-colored bats. We also found that abundance of tri-colored bats was influenced by length of culvert, elevation, number of sections, portal height, portal obstruction, aspect, external VPD, external temperature, and NDVI. With the current threats to tri-colored bat populations, there is a need to consider management of culvert roosts. In addition, it is imperative to further investigate the potential susceptibility to WNS of culvert-roosting bats at more southern latitudes for local and regional planning efforts