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A narrative in ecology is that prey modify traits to reduce predation risk, and the trait modification has costs large enough to cause ensuing demographic, trophic and ecosystem consequences, with implications for conservation, management and agriculture. But ecology has a long history of emphasising that quantifying the importance of an ecological process ultimately requires evidence linking a process to unmanipulated field patterns. We suspected that such process-linked-to-pattern (PLP) studies were poorly represented in the predation risk literature, which conflicts with the confidence often given to the importance of risk effects. We reviewed 29 years of the ecological literature which revealed that there are well over 4000 articles on risk effects. Of those, 349 studies examined risk effects on prey fitness measures or abundance (i.e., non-consumptive effects) of which only 26 were PLP studies, while 275 studies examined effects on other interacting species (i.e., trait-mediated indirect effects) of which only 35 were PLP studies. PLP studies were narrowly focused taxonomically and included only three that examined unmanipulated patterns of prey abundance. Before concluding a widespread and influential role of predation-risk effects, more attention must be given to linking the process of risk effects to unmanipulated patterns observed across diverse ecosystems.

This study examines the relationship between the individual motivational characteristics of young scientists (i.e. PhD students and post-docs) and their entrepreneurial intention, exploring also the mediating role of their third mission orientation. For this purpose, the authors considered the knowledge spillover theory of entrepreneurship at the level of the individual and the Theory of Planned Behaviour. Having university scientists as the unit of analysis, they used structural equation modelling to survey a sample of 337 young scientists working in a major Italian university. The authors were able to empirically identify the importance of third mission orientation as a mediating variable between scientists' motivational characteristics and their entrepreneurial intention. The entrepreneurial orientation is reinforced if scientists are also engaged in third mission activities. The findings offer valuable insights for policy makers and higher education managers to develop strategies that could enhance knowledge transfer activities and produce additional benefits for universities and societies.

Our ability to predict how species will respond to human-induced rapid environmental change (HIREC) may depend upon our understanding of transgenerational plasticity (TGP), which occurs when environments experienced by previous generations influence phenotypes of subsequent generations. TGP evolved to help organisms cope with environmental stressors when parental environments are highly predictive of offspring environments. HIREC can alter conditions that favored TGP in historical environments by reducing parents' ability to detect environmental conditions, disrupting previous correlations between parental and offspring environments, and interfering with the transmission of parental cues to offspring. Because of the propensity to produce errors in these processes, TGP will likely generate negative fitness outcomes in response to HIREC, though beneficial fitness outcomes may occur in some cases.

The welfare of wild animal populations is critically important to conservation, with profound implications for ecosystem health, biodiversity, and zoonotic disease transmission. Animal welfare is typically defined as the accumulated affective mental state of an animal over a particular time period. However, the assessment of animal welfare in the wild poses unique challenges, primarily due to the lack of universally applicable biomarkers. This perspective explores the potential role of the gut microbiome, a dynamic and non-invasive biomarker, as a novel avenue for evaluating animal welfare in wild animals. The gut microbiome, through interactions with the host's physiology, behavior, and cognition, offers a promising opportunity to gain insights into the well-being of animals. In this synthesis, we discuss the distinction between fitness and welfare, the complexities of assessing welfare in wild populations, and the linkages between the gut microbiome and aspects of animal welfare such as behavior and cognition. We lastly elucidate how the gut microbiome could serve as a valuable tool for wildlife managers, with the potential to serve as a non-invasive yet informative window into the welfare of wild animals. As this nascent field evolves, it presents unique opportunities to enhance our understanding of the well-being of wild animals and to contribute to the preservation of ecosystems, biodiversity, and human health. [ABSTRACT FROM AUTHOR]

Human activities catalyse risk avoidance behaviours in wildlife across taxa and systems. However, the broader ecological significance of human‐induced risk perception remains unclear, with a limited understanding of how phenotypic responses scale up to affect population or community dynamics. We present a framework informed by predator–prey ecology to predict the occurrence of non‐consumptive effects (NCE) and trait‐mediated indirect effects (TMIE) of anthropogenic disturbances. We report evidence from a comprehensive review of the different types of human‐induced behavioural and physiological phenotypic changes and their influence on vital rates and population parameters in wildlife. Evidence for human‐induced NCEs and TMIEs is mixed, with half of published studies finding a relationship between human activities, phenotypic change and population outcomes. The net effects of anthropogenic NCEs and TMIEs depend on the mismatch between the phenotypic response and the lethality of human activity. However, strong research biases in taxa, systems, human disturbance types and demographic measures prevent unified inference about the prevalence of population responses to human activities. Coexistence with and conservation of wildlife requires additional research linking human‐induced phenotypic change to population and community outcomes. [ABSTRACT FROM AUTHOR]

The relationship between body size and latitude has been the focus ofdozensof studies across many species. However, results of testing Bergmann's rule--that organisms in colder climates or at higher latitudes possess larger body sizes--have been inconsistent across studies. We investigated whether snowshoe hares (Lepus americanus Erxleben, 1777) follow Bergmann's rule by investigating differences in body mass using data from six published studies and from data of 755 individual hares captured from 10 populations across North America covering 26[degrees] of north latitude. We also explored alternative hypotheses related to variation in hare body mass, including winter severity, length of growing season, elevation, and snow depth. We found body mass of hares varied throughout their range, but the drivers of body mass differed based on geographic location. In northern populations, females followed Bergmann's rule, whereas males did not. In northern populations, male mass was related to mean snow depth. In contrast, in southern populations, body mass of both sexes was related to length of the growing season. These differences likely represent variation in the drivers of selection. Specifically, in the north, a large body size is beneficial to conserve heat because of low winter temperatures, whereas in the south, it is likely due to increased food supply associated with longer growing seasons. Key words: snowshoe hare, Lepus americanus, latitudinal variation, energy expenditure, food supply, winter, snow depth, growing season. Le lien entre la taille du corps et la latitude a fait l'objet de dizaines d'etudes portant sur de nombreuses especes. Les resultats des etudes visant a valider la regle de Bergmann, qui stipule que les organismes vivant en climat plus froid ou a plus haute altitude auraient des corps de plus grandes tailles, ne sont pas coherents d'une etude a l'autre. Nous avons verifie si les lievres d'Amerique (Lepus americanus Erxleben, 1777) suivaient la regle de Bergmann en examinant les differences de masse corporelle dans des donnees de six etudes publiees et pour 755 lievres captures de 10 populations reparties a la grandeur de l'Amerique du Nord, sur un territoire couvrant 26[degrees] de latitude nord. Nous avons aussi examine differentes hypotheses concernant les variations de la masse corporelle de lievres, touchant notamment a la rigueur de l'hiver, la duree de la periode vegetative, l'altitude et l'epaisseur de la neige. Nous avons constate que la masse corporelle des lievres varie dans toute leur aire de repartition, mais que les facteurs qui l'influencent different selon l'endroit. Dans les populations nordiques, les femelles suivent la regle de Bergmann, mais non les males. Dans les populations nordiques, la masse des males est reliee a l'epaisseur moyenne de la neige, alors que dans les populations meridionales, la masse corporelle des deux sexes est reliee a la duree de la periode vegetative. Ces differences representent vraisemblablement des variations des facteurs influant sur la selection. Plus precisement, au nord, une grande taille du corps est utile parce qu'elle facilite la conservation de chaleur pour faire face aux faibles temperatures hivernales, alors que dans le sud, elle est probablement due a un meilleur approvisionnement en nourriture associe a des periodes vegetatives plus longues. [Traduit par la Redaction] Mots-cles : lievre d'Amerique, Lepus americanus, variation latitudinale, depense energetique, approvisionnement en nourriture, hiver, epaisseur de la neige, periode vegetative., Introduction Latitudinal variation in body size is a phenomenon common across many taxa (McNab 1971; Ashton etal. 2000; Meiri and Dayan 2003). In particular, Bergmann's rule states that, within a [...]

In the age of global climate change, extreme climatic events are expected to increase in frequency and severity. Animals will be forced to cope with these novel stressors in their environment. Glucocorticoids (i.e. 'stress' hormones) facilitate an animal's ability to cope with their environment. To date, most studies involving glucocorticoids focus on the immediate physiological effects of an environmental stressor on an individual, few studies have investigated the long-term physiological impacts of such stressors. Here, we tested the hypothesis that previous exposure to an environmental stressor will impart lasting consequences to an individual's glucocorticoid levels. In semi-arid environments, variable rainfall drives forage availability for herbivores. Reduced seasonal precipitation can present an extreme environmental stressor potentially imparting long-term impacts on an individual's glucocorticoid levels. We examined the effects of rainfall and environmental characteristics (i.e. soil and vegetation attributes) during fawn-rearing (i.e. summer) on subsequent glucocorticoid levels of female white-tailed deer (Odocoileus virginianus) in autumn. We captured 124 adult (≥2.5-year-old) female deer via aerial net-gunning during autumn of 2015, 2016 and 2021 across four populations spanning a gradient of environmental characteristics and rainfall in the semi-arid environment of South Texas, USA. We found for every 1 cm decrease in summer rainfall, faecal glucocorticoid levels in autumn increased 6.9%, but only in lactating females. Glucocorticoid levels in non-lactating, female deer were relatively insensitive to environmental conditions. Our study demonstrates the long-lasting effects of environmental stressors on an individual's glucocorticoid levels. A better understanding of the long-term effects stressors impart on an individual's glucocorticoid levels will help to evaluate the totality of the cost of a stressor to an individual's welfare and predict the consequences of future climate scenarios. [ABSTRACT FROM AUTHOR]

Prey respond to predation risk by altering their morphology, physiology, and behavior, responses that may come at a cost to prey foraging and growth. However, their perception of risk may depend upon the environmental context in which the interaction occurs. Here, we examined how food availability influenced prey's responses to a nonlethal but free-ranging predator. We used an experimental mesocosm set-up of an intertidal system of green crab (Carcinus maenas) predators and dogwhelk snail (Nucella lapillus) prey, with blue mussels as the basal resource. We measured individual Nucella risk-aversion behavior (summed value of their habitat use) and their growth throughout the 28-day experiment. We found that when Nucella were exposed to predation risk, they had greater risk-aversion behavior when food was available as compared to when food was not. We also found that risk-aversion behavior increased over time in all treatments but that individuals exposed to predation risk with food always had greater risk-aversion behavior. Nucella had significantly more growth when provided with food as compared to without. In treatments with food, snails exposed to predation risk had significantly reduced growth compared to those not exposed to risk. In treatments without food, predation risk had no effect on growth. Our results support the hypothesis that greater resource availability significantly increases individual risk responses and the costs of risk avoidance, thus food magnifies risk-induced non-consumptive effects. They provide insights into context-based predation risk effects and how individuals may prioritize safety versus foraging depending upon perceived risk, food availability, and the costs of responding. [ABSTRACT FROM AUTHOR]

Body condition of animals influences the likelihood of surviving harsh environmental conditions, successfully reproducing, and resisting disease. The sum of these individual components of fitness, in turn, have consequences for the growth and persistence of wildlife populations. Here we compared the body mass and condition of adult female arctic ground squirrels (Urocitellus parryii plesius (Osgood, 1900)), an obligate hibernator, in source and sink habitats. We tested the hypothesis that adult females would be in poorer condition in the boreal forest than in adjacent meadows. We found that, during spring, postpartum females in forests weighed less (405 [+ or -] 7 vs. 437 ± 11 g; mean ± SE) and were in poorer condition (mean (± SE) residual of mass over structural size = -11.0 ± 10.2 vs. 20.5 ± 6.1 g) compared with females in meadow-source habitat. However, by the onset of entrance into hibernation in August, forest squirrels had reached parity with meadow squirrels and no difference was found in mass (519 ± 13 vs. 520 ± 15 g; mean ± SE) or condition (residual index = -0.01 ± 0.01 vs. 0.03 ± 0.01; mean ± SE). We suggest that for squirrels in formerly occupied boreal forests, (i) poor spring body condition decreased reproductive success and (ii) achieving compensatory growth, via increased foraging, comes at the costs of higher predation risk. These costs likely contributed to the recent local extinction of arctic ground squirrels in boreal forest habitat. Key words: arctic ground squirrel, body condition, body mass, boreal forest, climate change, extirpation, foraging strategy, Kluane, predation risk, population collapse, source-sink, Urocitellus parryii plesius, vigilance. L'embonpoint des animaux influence la probabilite de survie dans des conditions ambiantes difficiles, le succes de reproduction et la resistance aux maladies. La somme de ces differentes composantes de l'aptitude a, quant a elle, des consequences en ce qui concerne la croissance et la persistance des populations d'animaux sauvages. Nous comparons la masse corporelle et l'embonpoint de spermophiles arctiques (Urocitellus parryii plesius (Osgood, 1900)) femelles adultes, une espece hibernante infeodee, dans des habitats sources et puits. Nous verifions l'hypothese selon laquelle les femelles adultes presenteraient un moins bon embonpoint dans la foret boreale que dans les baissieres adjacentes. Nous avons constate que, au printemps, les femelles post-partum dans les forets presentaient une masse (405 ± 7 contre 437 ± 11 g; moyenne [+ or -] ET) et un embonpoint (residue moyenne (±ET) de la masse sur la taille structurale = -11,0 ± 10,2 contre 20,5 ± 6,1 g) inferieurs a ceux des femelles dans les habitats sources de baissiere. Cependant, au debut de l'entree en hibernation en aout, les spermophiles des forets avaient atteint la parite avec les spermophiles des baissieres et aucune difference de masse (519 ± 13 contre 520 ± 15 g; moyenne ± ET), ni d'embonpoint n'etait observee (indice residuel = -0,01 ± 0,01 contre 0,03 ± 0,01; moyenne ± ET). Nous proposons que, pour les spermophiles dans des forets boreales occupees anterieurement, (i) le faible embonpoint printanier reduisait le succes de reproduction et (ii) la compensation de la croissance par un approvisionnement accru vient au cout d'un risque de predation accru. Ce cout a probablement contribue a la disparition locale recente de spermophiles arctiques dans des habitats de foret boreale. [Traduit par la Redaction] Mots-cles : spermophile arctique, embonpoint, masse corporelle, foret boreale, changement climatique, disparition locale, strategie d'approvisionnement, Kluane, risque de predation, effondrement de populations, source-puits, Urocitellus parryii plesius, vigilance., Introduction For many mammals, body mass and body condition are important determinants of overwinter survival (Festa-Bianchet et al. 1997), reproductive success (Guinet et al. 1998), and susceptibility to disease (Beldomenico [...]