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Parasites can influence host population health and dynamics and are often an overlooked aspect of the ecology of ecosystems. Understanding the impacts of ecological interactions between parasites and small mammals can provide insights into ecosystem dynamics. We live trapped small mammals within the Apostle Islands archipelago (2017-2020) and assessed factors influencing the presence of mites from the Trombiculidae family. Archipelagos provide unique research opportunities because in small mammal-parasitic trombiculid systems, they are essentially closed systems. We detected trombiculids on 47% of red-backed vole (Myodes gapperi (Vigors, 1830)) individuals but rarely detected trombiculids on other species. We developed and ranked a set of a priori logistic regression models of trombiculid presence relative to habitat quality, host abundance, body condition, sex, and sexual maturity to identify factors significant in predicting trombiculid infection for M. gapperi. Parasitic trombiculids were more likely when M. gapperi abundance was high and body condition was poor; however, it is unknown whether trombiculids affect condition or if trombiculids are more likely to parasitize hosts in poor condition. The significance of host abundance may indicate density-dependent transmission. Our work suggests that host density and body condition are important factors influencing parasitism by trombiculids in M. gapperi populations. Key words: density dependence, host condition, Myodes gapperi, parasitism, red-backed vole, Trombiculidae Les parasites peuvent influencer la santé et la dynamique des populations de leurs hôtes et constituent souvent un aspect négligé de l'écologie des écosystèmes. La compréhension des impacts des interactions écologiques de parasites et de petits mammifères peut fournir de l'information sur la dynamique des écosystèmes. Nous avons piégé vivants de petits mammifères dans l'archipel des îles des Apôtres (2017-2020) et évalué les facteurs qui influencent la présence d'acariens de la famille des trombiculidés. Les archipels offrent des possibilités de recherche uniques parce que, pour des systèmes à petits mammifères-trombiculidés parasites, ils constituent essentiellement des systèmes fermés. Nous avons décelé des trombiculidés sur 47 % des campagnols à dos roux de Gapper (Myodes gapperi (Vigors, 1830)), mais rarement sur d'autres espèces. Nous avons élaboré et ordonné un ensemble de modèles de régression logistique a priori de la présence de trombiculidés en fonction de la qualité de l'habitat et de l'abondance, de l'embonpoint, du sexe et de la maturité sexuelle des hôtes afin de cerner les facteurs significatifs pour la prédiction d'infections aux trombiculidés de M. gapperi. Si la présence de trombiculidés parasites était plus probable quand l'abondance des campagnols était élevée et que leur embonpoint était faible, il n'est pas possible de dire si les trombiculidés ont une incidence sur l'embonpoint ou s'ils sont plus susceptibles de parasiter des hôtes de faible embonpoint. La significativité de l'abondance des hôtes pourrait refléter une transmission dépendante de la densité. Nos travaux donnent à penser que la densité et l'embonpoint des hôtes sont des facteurs importants qui influencent le parasitisme de trombiculidés dans les populations de M. gapperi. [Traduit par la Rédaction] Mots-clés : dépendance sur la densité, embonpoint de l'hôte, Myodes gapperi, parasitisme, campagnol à dos roux, trombiculidés, Introduction Parasites can influence the structure and function of ecosystems. Host manipulation by parasites can cause phe-notypic alterations that modify competition processes, food web structure and energy flow, as well [...]

Simple Summary: How people feel about large carnivores can be critical in determining the success of conservation efforts. In some cases, people's attitudes towards large carnivores are more influenced by policies dictating how people can interact with those species rather than the species themselves. Yet, the connections between policy and tolerance of large carnivores remain unclear. To better understand these connections, we surveyed residents of northern Wisconsin, USA, about wolves Canis lupus and wolf policies. We grouped survey respondents based on their general attitudes towards wolves and assessed whether respondents expected their tolerance of wolves to improve under different policy scenarios. Hunters, people with generally negative or ambivalent attitudes towards wolves, and people with wildlife conflict experience were more likely to expect their tolerance to improve under policy scenarios that allowed for the regulated killing of wolves under certain circumstances. However, we also observed important nuances in the relationship between tolerance of wolves and wolf policy. Large carnivore conservationists must balance conservation objectives with the preferences of local people. The fulcrum of this balance may shift over time as local preferences or species status change. Thus, monitoring local policy preferences may be just as important as carnivore population monitoring. Success in large carnivore conservation often hinges on local residents' tolerance towards those species. Feelings of powerlessness and frustration with wildlife policies can lead to intolerance of the species. In extreme cases, intolerance may manifest in poaching. Thus, changes in policy may influence the tolerance of wildlife. To examine the connections between policy and tolerance, we examined how policy scenarios influenced anticipated changes in tolerance to wolves Canis lupus. We administered a survey in 2015–2016 in the core wolf range within northern Wisconsin, USA. Using hierarchical cluster analysis, we clustered respondents into groups based on their current tolerance of wolves. We evaluated the behavioral intentions of the clusters and examined the influence of policy scenarios on respondents' anticipated changes in tolerance. Finally, using an information-theoretic model selection framework, we assessed the effects of tolerance clusters and demographic factors. The respondents were clustered into three clusters relative to their current tolerance towards wolves: positive, ambivalent, and negative. Each cluster exhibited significantly different behavioral intentions and anticipated changes in tolerance for all scenarios. In all scenarios, respondents who already held positive attitudes towards wolves were significantly less likely to report expected changes in tolerance toward wolves following changes in wolf management. However, respondents who held ambivalent or negative attitudes towards wolves were significantly more likely to report expected changes in tolerance towards wolves following changes in wolf management. Regarding a regulated wolf hunting and trapping season, we observed a Simpson's Paradox, wherein, when examined in aggregate, no clear pattern emerged, but when examined at the cluster level, important and intuitive patterns emerged. Our demographic model results suggest that policy changes resulting in greater state management authority over wolves, especially authority to implement certain forms of legal killing of wolves, could result in significant increases in tolerance for individuals who identify as hunters, have lost livestock to a predator, or are currently ambivalent or negative towards wolves. Our work elucidates the nuanced relationship between tolerance of wildlife and wildlife policy and identifies a potential ecological fallacy. [ABSTRACT FROM AUTHOR]

Management of wolves is controversial in many jurisdictions where wolves live, which underscores the importance of rigor, transparency, and reproducibility when evaluating outcomes of management actions. Treves and Louchouarn 2022 (hereafter TL) predicted outcomes for various fall 2021 hunting scenarios following Wisconsin's judicially mandated hunting and trapping season in spring 2021, and concluded that even a zero harvest scenario could result in the wolf population declining below the population goal of 350 wolves specified in the 1999 Wisconsin wolf management plan. TL further concluded that with a fall harvest of > 16 wolves there was a "better than average possibility" that the wolf population size would decline below that 350-wolf threshold. We show that these conclusions are incorrect and that they resulted from mathematical errors and selected parameterizations that were consistently biased in the direction that maximized mortality and minimized reproduction (i.e., positively biased adult mortality, negatively biased pup survival, further halving pup survival to November, negatively biased number of breeding packs, and counting harvested wolves twice among the dead). These errors systematically exaggerated declines in predicted population size and resulted in erroneous conclusions that were not based on the best available or unbiased science. Corrected mathematical calculations and more rigorous parameterization resulted in predicted outcomes for the zero harvest scenario that more closely coincided with the empirical population estimates in 2022 following a judicially prevented fall hunt in 2021. Only in scenarios with simulated harvest of 300 or more wolves did probability of crossing the 350-wolf population threshold exceed zero. TL suggested that proponents of some policy positions bear a greater burden of proof than proponents of other positions to show that "their estimates are accurate, precise, and reproducible". In their analysis, TL failed to meet this standard that they demanded of others. [ABSTRACT FROM AUTHOR]

The ecology of many arboreal ectotherms is poorly understood because of access constraints to the forest canopy. For example, despite their common name, Gray Treefrogs (Hyla versicolor) are understudied in arboreal habitats. Advancements in camera trap technology and tree-climbing techniques have created new opportunities to study arboreal species. Using arboreal camera trapping and time-lapse photography, we implemented the first study of H. versicolor behavior in the canopy. We examined seasonal and diel patterns of activity, microhabitat use, and effects of relative humidity and temperature on H. versicolor activity in eastern white pine (Pinus strobus) canopies. We installed camera traps at three research sites in northern Wisconsin, USA, spanning a 57-km north–south transect, and maintained them for multiple years. We detected H. versicolor events, of all sex–age classes, at two of our research sites. Use of time-lapse photography significantly improved our ability to detect H. versicolor in the canopy. Hyla versicolor individuals were active in the canopy every year of the study (2015–18), but predominantly during the summer, and peak diel activity occurred predominantly during the night (between 2100 and 2300 h). Hyla versicolor activity significantly increased as relative humidity and temperature increased. Hyla versicolor individuals were significantly more active in the upper canopy compared with other canopy locations and selected for the top side of branches. Our results highlight that H. versicolor frequent arboreal habitats of P. strobus canopies. Although further research is needed, our work lays a foundation of H. versicolor ecology within the canopy. This research also demonstrates the feasibility of using arboreal camera traps with time-lapse settings to study ectotherms in forest canopies. [ABSTRACT FROM AUTHOR]

White‐nose syndrome is a fungal disease that is threatening bat populations across North America. The disease primarily affects cave‐hibernating bats by depleting fat reserves during hibernation and causing a range of other physiological consequences when immune responses are suppressed. Since it was first detected in 2006, the disease has killed millions of bats and is responsible for extensive local extinctions. To better understand the effects of white‐nose syndrome on various bat species, we analyzed summer acoustic survey data collected from 2016 to 2020 at nine US National Parks within the Great Lakes region. We examined the effect that white‐nose syndrome, time of the year relative to pup volancy, habitat type, and regional variation (i.e., park) have on the acoustic abundance (i.e., mean call abundance) of six bat species. As expected, little brown bat (Myotis lucifugus) and northern long‐eared bat (Myotis septentrionalis), both hibernating species, experienced a significant decline in acoustic abundance following white‐nose syndrome detection. We observed a significant increase in acoustic abundance as white‐nose syndrome progressed for hoary bats (Lasiurus cinereus) and silver‐haired bats (Lasionycteris noctivagans), both migratory species that are not impacted by the disease. Contrary to our predictions, we observed an increase in big brown bat (Eptesicus fuscus; hibernating) acoustic abundance and a decrease in eastern red bat (Lasiurus borealis; migratory) acoustic abundance following the detection of white‐nose syndrome. We did not observe any significant changes after the onset of white‐nose syndrome in the seasonal patterns of acoustic activity related to pup volancy, suggesting that production or recruitment of young may not be affected by the disease. Our results suggest that white‐nose syndrome is affecting the acoustic abundance of certain species; however, these changes may not be a result of reduced reproductive success caused by the disease. In addition, species population dynamics may be indirectly affected by white‐nose syndrome as a result of reduced competition or a foraging niche release. We also found that for parks located at higher latitudes, little brown bat and northern long‐eared bat were more likely to experience greater declines in acoustic abundance as a result of white‐nose syndrome. Our work provides insight into species‐specific responses to white‐nose syndrome at a regional scale and examines factors that may facilitate resistance or resiliency to the disease. [ABSTRACT FROM AUTHOR]

The dynamic behavior of magnetic fields surrounding adjacent current-carrying conductors is investigated for the purpose of point-field-based current sensing. The influence of eddy currents on magnetic field distribution over the useful spectrum (dc to 1 MHz) is quantified by using a spatially dependent metric, the 5% flat bandwidth (FBW). A comparison of field distributions at dc and 1 MHz shows the origin of the FBW function, which is unique to each conductor's cross section and nearby environment. The FBW fields for several different conductor geometries are analyzed. Superposition is used for conductor geometries that have multiple currents. A method for determining optimal field detector placement using optimization functions is introduced. Index Terms--Current sensing, field decoupling, giant magneto-resistive, magnetic field detectors, proximity effect, skin effect, superimposed fields.

Cardiac fibroblast (CF) proliferation and differentiation into hypersecretory myofibroblasts can lead to excessive extracellular matrix (ECM) production and cardiac fibrosis. In turn, the ECM produced can potentially activate CFs via distinct feedback mechanisms. To assess how specific ECM components influence CF activation, isolated CFs were plated on specific collagen substrates (type I, III, and VI collagens) before functional assays were carried out. The type VI collagen substrate potently induced myofibroblast differentiation but had little effect on CF proliferation. Conversely, the type I and III collagen substrates did not affect differentiation but caused significant induction of proliferation (type I, 240.7 [+ or -] 10.3%, and type III, 271.7 [+ or -] 21.8% of basal). Type I collagen activated ERK 1/2, whereas type III collagen did not. Treatment of CFs with angiotensin II, a potent mitogen of CFs, enhanced the growth observed on types I and III collagen but not on the type VI collagen substrate. Using an in vivo model of myocardial infarction (MI), we measured changes in type VI collagen expression and myofibroblast differentiation after post-MI remodeling. Concurrent elevations in type VI collagen and myofibroblast content were evident in the infarcted myocardium 20-wk post-MI. Overall, types 1 and II1 collagen stimulate CF proliferation, whereas type VI collagen plays a potentially novel role in cardiac remodeling through facilitation of myofibroblast differentiation. cardiac fibroblasts; fibrosis; extracellular matrix; [alpha]-smooth muscle actin

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Island biogeography theory is a foundational ecological concept that describes how island or habitat patch size and isolation predict biodiversity, but few have studied how the effects of island biogeography vary with life history characteristics of temperate mammal communities. From 2014 to 2020, we surveyed volant and nonvolant mammals within the Apostle Islands archipelago (Wisconsin, USA) using camera trapping, live trapping, and acoustic monitoring. We used linear regression and information‐theoretic model selection to evaluate the effects of island size and isolation on indices of biodiversity. We also examined the effects of life history characteristics (i.e., body mass, winter inactivity) on the relative abundance and distribution of each species on the islands and the mainland. For volant mammals, island size and isolation were not associated with any metrics of diversity. We found island size was positively associated with nonvolant mammal species richness and diversity, but not species evenness. Island isolation was not a significant predictor for small nonvolant mammal diversity, although both size and isolation appeared to influence island biogeography of medium‐large nonvolant mammals. We also found that the interaction between winter inactivity and body mass influenced the vagility of nonvolant mammals in the archipelago. Our results suggest that life history characteristics are important in mediating species responses to biogeography, supporting the dispersal‐limitation nonequilibrium view of island biogeography theory, particularly for nonvolant mammals. [ABSTRACT FROM AUTHOR]

Copyright of Methods in Ecology & Evolution is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In continuation of our interest in long-range "through-space" H-F and C-F spin-spin coupling in planar aromatic molecules,[[1]] we desired to explore the presence (or absence) of such coupling between the fluorine and the methyl group as possibly mediated via the nitrogen lone pair in 4-fluoro-5-methylacridine ( B 1 b ). Diazotization was carried out using nitrosylsulfuric acid, followed by fluoboric acid to afford 4-(5-methylacridino)diazonium tetrafluoroborate ( B 8 b ) in 88% yield. An examination of the proton and carbon NMR spectra of B 1 b revealed no spin-spin coupling (>0.5 Hz) between the fluorine and the methyl group hydrogens and carbon, respectively. [Extracted from the article]

Selective pressures (i.e. resource limitation and competitive interaction) that drive the composition of ecological communities vary, and often operate on different ecological scales (ecological variables across varying spatial scales) than observed patterns. We studied the drivers of distribution and abundance of the American marten (Martes americana) and the carnivore community at three ecological scales on a Great Lakes island archipelago using camera traps. We found different drivers appeared important at each ecological scale and studying any of the three scales alone would give a biased understanding of the process driving the system. Island biogeography (resource limitation) was most important for carnivore richness, with higher richness on larger islands and lower richness as distance from the mainland increased. Marten presence on individual islands appeared to be driven by island size (resource limitation) and human avoidance (competitive interaction). Marten abundance at camera trap sites was driven by the cascading effect of coyotes (Canis latrans) on fishers (Pekania pennanti) (competitive interaction). Incorporating three ecological scales gave novel insights into the varying effects of resource limitation and competitive interaction processes. Our data suggests that ecological communities are structured through multiple competing ecological forces, and effective management and conservation relies on our ability to understand ecological forces operating at multiple ecological scales. [ABSTRACT FROM AUTHOR]

The occurrence of biofluorescence across Mammalia is an area of active study. We examined three specimens of the platypus (Ornithorhynchus anatinus) from Tasmania and New South Wales, Australia, housed in the Field Museum of Natural History (Chicago, Illinois, USA) and the University of Nebraska State Museum (Lincoln, Nebraska, USA) under visible light and ultraviolet (UV) light. The pelage of the animals appeared uniformly brown under visible light and green or cyan under UV light, due to fluoresced wavelengths that peaked around 500 nm. Our observations are the first report of biofluorescence in a monotreme mammal. [ABSTRACT FROM AUTHOR]

The Sleeping Beauty (SB) transposon system can insert sequences into mammalian chromosomes, supporting long-term expression of both reporter and therapeutic genes. Hematopoietic progenitor cells (HPCs) are an ideal therapeutic gene transfer target as they are used in therapy for a variety of hematologic and metabolic conditions. As successful SB-mediated gene transfer into human CD34+ HPCs has been reported by several laboratories, we sought to extend these studies to the introduction of a therapeutic gene conferring resistance to methotrexate (MTX), potentially providing a chemoprotective effect after engraftment. SB-mediated transposition of hematopoietic progenitors, using a transposon encoding an L22Y variant dihydrofolate reductase fused to green fluorescent protein, conferred resistance to methotrexate and dipyridamole, a nucleoside transport inhibitor that tightens MTX selection conditions, as assessed by in vitro hematopoietic colony formation. Transposition of individual transgenes was confirmed by sequence analysis of transposon-chromosome junctions recovered by linear amplification-mediated PCR. These studies demonstrate the potential of SB-mediated transposition of HPCs for expression of drug resistance genes for selective and chemoprotective applications. [ABSTRACT FROM AUTHOR]

Rapid change in wildlife populations can challenge managers to promote species conservation while maintaining public support for wildlife. Wolf management during recolonization in Wisconsin, United States demonstrates the complexities of inconsistent management authority, public attitudes, and illegal killing of wolves. State management authority to control depredating wolves oscillated during a period of intense sociopolitical conflict over wolf status under the federal Endangered Species Act. We demonstrate that swings in wolf status led to inconsistent management authority, declining local public support for wolves, and possibly the unintended backlash of more illegal kills and a legislatively mandated public wolf hunt. A new Wildlife Management Matrix illustrates an idealized relationship between lethal control options and perceptions of wildlife. Moderating the sociopolitical drivers of swings in policy over short periods is essential to allow wildlife managers greater flexibility in achieving species-specific goals. To our knowledge, this research provides the first demonstrated link between illegal wildlife killing and management authority under the Endangered Species Act, and suggests that illegal behavior may be moderated with responsible and effective wildlife management programs. We recommend states avoid prescriptive harvest legislation, and we suggest a more incremental shift from federal to state management authority. [ABSTRACT FROM AUTHOR]