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Resource selection informs understanding of a species' ecology and is especially pertinent for invasive species. Since introduced to Canada, wild pigs (Sus scrofa Linnaeus, 1978) remain understudied despite recognized negative impacts on native and agricultural systems globally. Elsewhere in North America, pigs typically use forests and forage in agricultural crops. We hypothesized Canadian wild pigs would behave similarly, and using GPS locations from 15 individuals, we examined diel and seasonal resource selection and movement in the Canadian prairie region. Forests were predominately selected during the day, while corn (Zea mays L.), oilseeds, and wheat (Triticum aestivum L.) were predominately selected at night. Forests and corn were consistently selected throughout the growing season. Wetlands and forests showed greater use rates than other habitats, with evident trade-offs as crop use increased with the timing of maturation. Activity was consistent with foraging in growing crops. Results indicate diel patterns were likely a function of short-term needs to avoid daytime anthropogenic risk, while seasonal patterns demonstrate how habitats that fill multiple functional roles--food, cover, and thermoregulation--can be optimized. Understanding selection by invasive species is an important step in understanding their potential environmental impacts in novel environments and informs their management. Key words: wild pigs, Sus scrofa, habitat selection, residency time, persistence velocity, Canadian prairies La sélection de ressources permet de mieux comprendre l'écologie des espèces, tout particulièrement en ce qui concerne les espèces envahissantes. Depuis leur introduction au Canada, les sangliers (Sus scrofa Linnaeus, 1758) demeurent peu étudiés, malgré leurs impacts négatifs établis sur des systèmes indigènes et agricoles à l'échelle mondiale. Ailleurs en Amérique du Nord, les sangliers utilisent typiquement des forêts et se nourrissent de cultures. Nous avons postulé que les sangliers canadiens se comporteraient de manière semblable et, en utilisant les positions GPS de 15 spécimens, nous avons étudié leurs motifs nycthéméraux et saisonniers de sélection de ressources et de déplacement dans la région des prairies canadiennes. Durant la journée, des forêts sont sélectionnées de manière prédominante, alors que, durant la nuit, des cultures de maïs (Zea mays L.), d'oléagineuses et de blé (Triticum aestivum L.) sont sélectionnées de manière prédominante. Des forêts et des cultures de maïs sont uniformément sélectionnées tout au long de la période végétative. Les fréquences d'utilisation de milieux humides et de forêts sont plus élevées que celles d'autres habitats, et sont associées à des compromis évidents avec l'augmentation de l'utilisation des cultures au fil de leur maturation. Les motifs d'activité concordent avec une quête de nourriture dans des cultures en croissance. Les résultats indiquent que les motifs nycthéméraux sont probablement fonction du besoin à court terme d'évitement de risques d'origine humaine durant le jour, alors que les motifs saisonniers illustrent comment des habitats qui jouent plusieurs rôles fonctionnels (alimentation, couvert et thermorégulation) peuvent être optimisés. La compréhension de la sélection par des espèces envahissantes constitue un pas important pour comprendre leurs impacts environnementaux potentiels dans de nouveaux milieux et éclairer leur gestion. [Traduit par la Rédaction] Mots-clés : sanglier, Sus scrofa, sélection d'habitats, temps de résidence, vitesse de persistance, prairies canadiennes, Introduction Resource selection is a scale-dependent process, with spatial and temporal scale influencing the contribution of various environmental factors (e.g., landcover; Mayor et al. 2009) on animal landscape-use patterns. While [...]

Untangling the abiotic and biotic feedback mechanisms driving animal movements and ranges is a core question in ecology, yet progress is hampered by inadequate modelling procedures. Here we show how a recently developed process‐based modelling approach, combining step‐selection functions and individual‐based models, enables a flexible method to infer movement drivers and multi‐scale emergent space use patterns. As a case study, we examine the movement behaviours of a highly invasive social generalist (wild pigs, Sus scrofa) in relation to conspecific space use and multiple land cover types in a complex agricultural landscape, showing that social interactions are predominantly more important to this species than selection for land cover. Thus, animal movement studies should not neglect the effects of sociality when inferring resource driven movements and, crucially, use multi‐scale techniques that incorporate movement processes to untangle drivers of animal space use. [ABSTRACT FROM AUTHOR]

Having reproducible and transparent science‐based processes in wildlife management ensures the integrity of decision making. These processes are particularly important when establishing harvest frameworks, as guiding information in the peer‐reviewed literature is limited. We provide an example using multiple data sets, whose products guided aspects of the development of a harvest framework for a population of recolonizing American black bears (Ursus americanus) in Missouri, USA. To characterize the spatial distribution of harvest, we used 10 years (2010–2019) of black bear global positioning system (GPS) location data and 30 years (1991–2020) of sightings data to assess spatial vulnerability to harvest as the intersection among information on bear occurrence, bear sightings, and hunter land‐use tendencies (i.e., the avoidance of steep slopes, large distances from roads). We then used the spatial vulnerability assessment, information on the distribution of public and private lands, and easily discernable boundaries (i.e., major highways, rivers) to suggest boundaries for bear management zones. Additionally, to identify the timing of harvest that would limit female harvest bias, we assessed the temporal vulnerability of harvest using sex‐based changes in average daily step lengths and monthly utilization distribution sizes during fall. Black bear occurrence and sighting propensity was greater in southwestern Missouri, and potential hunter land use appeared pervasive across the landscape given the lack of landscape features that would disincentivize use. Given the influence of black bear occurrence and sighting propensity, spatial harvest vulnerability diminished from southern and southeastern to central portions of Missouri, with areas north of the Missouri River not a part of the established black bear range. We consequently divided areas south of the Missouri River into 3 black bear management zones: a small southwestern zone with primarily private lands and high harvest vulnerability, a southeastern zone that encompassed considerable public lands and moderate amounts of vulnerability, and a central zone that was composed mainly of areas of low vulnerability. Temporally, males did not exhibit movement‐based changes, but females became less active after the first week of October and used 63.9% less area through fall. Based on movements rates of males and females, a hunting season after the first week of October could reduce the likelihood of females being harvested. Harvests from the black bear harvest season in 2021 suggest that the proportion of bears harvested in each zone was similar in distribution to the proportion of permits allocated across zones with no harvest sex bias, which was aligned with agency goals. Animal movement and space use data products can guide harvest framework decision‐making. [ABSTRACT FROM AUTHOR]

Perceived predation risk alters prey behaviour and physiology, but few studies have examined downstream consequences on prey demography in wild populations. Perceived predation risk could alter adult reproductive performance via reduced investment in offspring quality and post-birth care. We manipulated perceived predation risk in snowshoe hare (Lepus americanus Erxleben, 1777) by exposing pregnant mothers to chases by a domestic dog (Canis familiaris Linnaeus, 1758). Litter size was comparable between risk-augmented and control groups, but treated females had more stillbirths and gave birth to leverets of lower body condition. Leverets from risk-augmented females had 88% higher 40-day mortality rate. Maternally preventable causes of death like starvation or predation by red squirrel (Tamiasciurus hudsonicus (Erxleben, 1777)) caused this difference, particularly during the nursing period. Risk-augmented mothers were always more active than controls, but the difference was greatest during the nursing period. We found that perceived predation risk reduces maternal productivity pre- and post-partum, implying downstream consequences to populations. Because our treatment ended before parturition, we can link offspring performance such as survival and behaviour specifically to maternal life-history trade-offs, which has not been shown in a wild mammal. [ABSTRACT FROM AUTHOR]

According to the structural‐function hypothesis, the eggshell pigment protoporphyrin, deposited at weak spots, can strengthen the shell structure when calcium is lacking in avian species. However, this hypothesis has not been tested in species that produce pigmented eggs of uniform ground colour without spotting patterns. We tested the structural‐function hypothesis using 435 eggs produced on seven calcium diets (0.2–4.5%) given to Common Pheasants Phasianus colchicus, a species that produces a large number of eggs on a low‐calcium diet with unspotted eggshells composed of a uniform ground colour of mainly protoporphyrin. We found that pheasants on the lowest calcium diet (0.2%), which had thinner eggshells, produced eggs containing more protoporphyrin‐based coloration than four of six other diets, suggesting this species employs pigmentation as ground colour to strengthen eggshells when available calcium is low. Our results provide the first, at least partial support for a structural function for eggshell pigments producing ground colour without spotting in a species that is often calcium‐limited. This pattern may be more widespread in other ground‐nesting taxa that also produce large numbers of eggs with protoporphyrin‐based ground colour and are potentially limited by calcium during breeding. [ABSTRACT FROM AUTHOR]

Understanding the quality of seed dispersal effectiveness of frugivorous species can elucidate how endozoochory structures tropical forests. Large seeds, containing more resources for growth, and gut passage by frugivores, which remove seed pulp, both typically enhance the speed and probability of germination of tropical seeds. However, the interaction of seed size and gut passage has not been well studied. We assessed the role of two species of toucans (Ramphastos spp.) in seed germination of the tropical tree Eugenia uniflora , which produces seeds that vary considerably in size (3.7–14.3 mm), using 151 control and 137 regurgitated seeds in germination trials. We found that toucan regurgitation did not increase germination success, although 93.4% germinated compared to 76.8% of control seeds; however, larger seeds germinated more often at faster rates. Although only marginally significant, germination rates were 3.6× faster when seeds were both large and regurgitated by toucans, demonstrating that toucan regurgitation can disproportionally benefit larger E. uniflora seeds. As tropical forests are increasingly disturbed and fragmented by human activities, the ability of toucans to continue providing seed dispersal services to degraded habitats may be vital to the persistence of many tropical plants that contain larger seeds and depend on larger dispersers. [ABSTRACT FROM AUTHOR]

Despite continued global declines in large carnivore abundance and distribution, some species are recovering. In North America, these recoveries can occur in large areas of suitable habitat in or near areas of human development, increasing the likelihood of human–carnivore conflicts. Understanding the intersection among habitat suitability, connectivity and human–carnivore conflicts can aid in conflict prevention and mitigation.We used GPS collar data from 97 bears and conflict reports collected from 1991 to 2020 to examine black bear Ursus americanus habitat suitability and landscape connectivity in relation to community‐level human–bear conflict occurrences and conflict rates in Missouri, USA. We used conflict–landscape relationships to predict potential community‐level human–bear conflicts given black bear recolonization.Suitable habitat for black bears comprised about 29% of Missouri and was predominantly forest and shrub cover with low habitat fragmentation and human density, and greater spring vegetation productivity. Landscape connectivity was greatest in south‐central Missouri with limited connectivity in northern and eastern portions of the state.Conflict rates were low (61 of 94 communities had 1–2 reported conflicts over 30 years), increased 6.5‐fold from 2000 to 2020, and 75% involved black bear use of anthropogenic food. The presence and rate of conflicts increased with greater amounts of suitable habitat, landscape connectivity and community size, with conflict rate also positively associated with patch density and aggregation and negatively associated with patch area. Of 1,010 communities in Missouri, we identified 99 communities with increased risk of human–bear conflicts based on surrounding landscape characteristics.Synthesis and applications. Our framework integrating landscape attributes and conflict reports can successfully identify communities at greater potential of human–carnivore conflict. In our Missouri case study, we identified 99 out of 1,010 communities which have increased risk of human–bear conflicts, knowledge which will increase the efficiency of education and mitigation rollouts as black bears re‐establish. This framework allows managers to identify communities at greater risk of conflict for many conflict‐prone species and helps prioritize communities for education and conflict mitigation actions, facilitating long‐term coexistence. [ABSTRACT FROM AUTHOR]

ABSTRACT Peer review is pivotal to science and academia, as it represents a widely accepted strategy for ensuring quality control in scientific research. Yet, the peer-review system is poorly adapted to recent changes in the discipline and current societal needs. We provide historical context for the cultural lag that governs peer review that has eventually led to the system's current structural weaknesses (voluntary review, unstandardized review criteria, decentralized process). We argue that some current attempts to upgrade or otherwise modify the peer-review system are merely sticking-plaster solutions to these fundamental flaws, and therefore are unlikely to resolve them in the long term. We claim that for peer review to be relevant, effective, and contemporary with today's publishing demands across scientific disciplines, its main components need to be redesigned. We propose directional changes that are likely to improve the quality, rigour, and timeliness of peer review, and thereby ensure that this critical process serves the community it was created for. [ABSTRACT FROM AUTHOR]

On 3 May 2016, we observed two Merlins (Falco columbarius) copulating near Hungry Lake in southwestern Yukon. We recorded Merlins frequently from May until the beginning of July and observed them defending the area from Common Ravens (Corvus corax) on two occasions, an activity indicative of a nesting pair. This is the first breeding record for Merlins in southern Yukon, as previous records have documented the breeding range only in central and northern parts of the territory. Here, we summarize historical sightings and breeding reports throughout southern Yukon since 1975 and fill a gap in the breeding range of this species. [ABSTRACT FROM AUTHOR]

The use of remote sensing to monitor animal populations has greatly expanded during the last decade. Drones (i.e., Unoccupied Aircraft Systems or UAS) provide a cost- and time-efficient remote sensing option to survey animals in various landscapes and sampling conditions. However, drone-based surveys may also introduce counting errors, especially when monitoring mobile animals. Using an agent-based model simulation approach, we evaluated the error associated with counting a single animal across various drone flight patterns under three animal movement strategies (random, directional persistence, and biased toward a resource) among five animal speeds (2, 4, 6, 8, 10 m/s). Flight patterns represented increasing spatial independence (ranging from lawnmower pattern with image overlap to systematic point counts). Simulation results indicated that flight pattern was the most important variable influencing count accuracy, followed by the type of animal movement pattern, and then animal speed. A  awnmower pattern with 0% overlap produced the most accurate count of a solitary, moving animal on a landscape (average count of 1.1 ± 0.6) regardless of the animal's movement pattern and speed. Image overlap flight patterns were more likely to result in multiple counts even when accounting for mosaicking. Based on our simulations, we recommend using a lawnmower pattern with 0% image overlap to minimize error and augment drone efficacy for animal surveys. Our work highlights the importance of understanding interactions between animal movements and drone survey design on count accuracy to inform the development of broad applications among diverse species and ecosystems., Competing Interests: The authors have no conflict of interest., (© 2024 The Author(s). Ecology and Evolution published by John Wiley & Sons Ltd.)

Ex situ amphibian populations can experience reproductive dysfunction due to the absence of environmental cues that trigger reproductive events. Assisted reproductive technologies (ART) for amphibians, specifically exogenous hormone regimens, can circumvent these external signals to induce gametogenesis and gamete release. Currently, the use of the mammalian reproductive hormones gonadotropin-releasing hormone (GnRH) and human chorionic gonadotropin (hCG) are used in a species-specific manner to stimulate amphibian breeding. Hormones or hormone mixtures that are effective in all breeding scenarios would provide the best option for conservation practitioners and some commercial products are already in use for breeding other ectotherms. Ovaprim®, which contains salmon GnRH analogue (sGnRHa) and the dopamine antagonist domperidone (DOM), is effective in fish aquaculture and may be effective for amphibians. To test this hypothesis, we treated Fowler's toads ( Anaxyrus fowleri ) with either sGnRHa alone, a high or low dose of Ovaprim® or hCG. We then compared spermiation response, sperm quantity and quality parameters, and changes in animal mass over time within each treatment. We found administration of Ovaprim® resulted in more males producing sperm with better motility compared to administration of sGnRHa alone. In addition, the Ovaprim® and sGnRHa treatments resulted in lower response rates, lower sperm motilities, more abnormal sperm, and higher aggregations of sperm compared to the hCG treatment. Furthermore, Ovaprim®-treated males gained significant mass, suggesting an anti-diuretic effect of DOM. Together, these results show that neither Ovaprim® nor sGnRHa, at the concentrations tested, are likely suitable replacements for hCG in ex situ bufonid breeding programmes and that hormone mixtures developed for fish may have limited transferability to new world toad species., Competing Interests: The authors have no conflicts of interest to declare., (© The Author(s) 2024. Published by Oxford University Press and the Society for Experimental Biology.)