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Abstract Protected areas serve as population strongholds for many large carnivores, with multi‐use landscapes along their borders forming the front‐lines of wildlife conservation. Understanding large carnivore population dynamics within working landscapes is difficult where anthropogenic mortality is high and unregulated. This study focused on working ranches, where killing jaguars (Panthera onca) and their prey was prohibited, to gain insight into jaguar population potential across multi‐use landscapes. Faced with forest fragmentation, presence of domestic livestock, and dynamic land‐use practices, we expected jaguar populations in working landscapes to be predominantly male and transient, with low cub production, and inflated population densities in remnant forest patches, versus protected areas where we expected native forest habitat and stable jaguar territories. Using camera traps and spatial‐capture recapture analyses, we observed that male jaguars demonstrated larger‐scale movements and were more detectable than females (0.07 ± 0.01 SE vs. 0.02 ± 0.01 SE) in both working and protected landscapes. Female jaguars in ranches traveled farther than females in parks. Carnivore density increased with forest cover and wild prey activity, decreased with domestic prey activity, and was marginally higher in ranches (4.08 individuals/100 km2 ± 0.73 SE) than in parks (3.59 individuals/100 km2 ± 0.64 SE). Females outnumbered males in both landscapes (2.20–2.60 females/100 km2 vs. ~1.60 males/100 km2), although local male density reached up to 11.00 males/100 km2 in ranches (vs. 3.50 males/100 km2 in parks). While overall jaguar density was patchier in protected areas (x̿ = 0.69 parks, 0.54 ranches), inter‐annual patchiness was higher within ranches (Moran's I = 0.49–0.60 ranches, 0.69–0.70 parks), reflecting changes in cattle management. Despite major habitat alterations, working landscapes can support carnivore densities equivalent to (or exceeding that of) unmodified forest habitat, provided that wildlife‐tolerant ranching practices are maintained.

O Pantanal é uma área importante para a conservação da onça-pintada (Panthera onca) e da onça-parda (Puma concolor). No entanto, o bioma possui peculiaridades que tornam a conservação de grandes felinos complexa e desafiadora. A predação do gado gera conflitos entre onças e fazendeiros, que tradicionalmente resultam na eliminação oportunista, porém sistemática, dos predadores. Por outro lado, é crescente entre os fazendeiros o reconhecimento da necessidade de conservar as onças, desde que seja resolvido, ou pelo menos diminuído em níveis toleráveis, o prejuízo que elas causam. Nesse contexto, é importante entender a dinâmica da predação, a fim de identificar ações que possam diminuir efetivamente o seu impacto econômico. Aspectos culturais também têm grande importância, influenciando diretamente na decisão de abater uma onça ou tolerar sua presença. Neste artigo, apresentamos e discutimos as características e a dinâmica da predação de espécies nativas e do gado doméstico por onças no Pantanal, em particular a onça-pintada. Além disso, descrevemos aspectos pessoais, sociais e culturais do conflito, e discutimos suas implicações para a conservação das onças, destacando a importância de entender e envolver os diferentes atores ligados à conservação dessas espécies.

Capturing small carnivores is often necessary for obtaining key ecological data. We compared the efficiency of box and leg-hold traps, using live and dead bait, to capture six carnivore species (Herpailurus yagouaroundi (É. Geoffroyi, 1803), Leopardus tigrinus (Schreber, 1775), Nasua nasua (Linnaeus, 1766), Cerdocyon thous (Linnaeus, 1766), Eira barbara (Linnaeus, 1758), and Galictis cuja (Molina, 1782)). The use of leg-hold traps significantly increased the capture rate of carnivores (5.77%) and non-target species (non-carnivores, 11.54%). Dead bait significantly attracted more non-carnivores than carnivores and live bait was more efficient for capturing carnivores (2.56%) than non-carnivores (0.77%). Both box and leg-hold traps caused some minor injuries (swelling and claw loss). We provide recommendations for the ethical use of these trap and bait types. Rev. Biol. Trop. 55 (1): 315-320. Epub 2007 March. 31.La captura de pequeños carnívoros es una práctica común para obtener datos ecológicos. Comparamos la eficiencia de cepos (trampas acolchadas) y trampas tomahawk para capturar seis especies carnívoras (Herpailurus yagouaroundi (É. Geoffroyi, 1803), Leopardus tigrinus (Schreber, 1775), Nasua nasua (Linnaeus, 1766), Cerdocyon thous (Linnaeus, 1766), Eira barbara (Linnaeus, 1758), and Galictis cuja (Molina, 1782)), utilizando carnadas vivas y muertas. Con los cepos se incrementó significativamente la tasa de captura de carnívoros (5.77%) y otros mamíferos (no-carnívoros, 11.54%). La carnada muerta atrajo significativamente mas no-carnívoros que carnívoros, mientras que con la carnada viva se capturaron más carnívoros (2.56% vs 0.77% no-carnívoros). Ambos tipos de trampas; cepos y tomahawk, causaron algunas pequeñas lastimaduras (inflamación y pérdida de garras). Hacemos algunas recomendaciones para el uso ético de este tipo de trampas y cebos.

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Habitat fragmentation can promote patches of small and isolated populations, gene flow disruption between those populations, and reduction of local and total genetic variation. As a consequence, these small populations may go extinct in the long-term. The ocelot (Leopardus pardalis), originally distributed from Texas to southern Brazil and northern Argentina, has been impacted by habitat fragmentation throughout much of its range. To test whether habitat fragmentation has already induced genetic differentiation in an area where this process has been documented for a larger felid (jaguars), we analyzed molecular variation in ocelots inhabiting two Atlantic Forest fragments, Morro do Diabo (MD) and Iguaçu Region (IR). Analyses using nine microsatellites revealed mean observed and expected heterozygosity of 0.68 and 0.70, respectively. The MD sampled population showed evidence of a genetic bottleneck under two mutational models (TPM = 0.03711 and SMM = 0.04883). Estimates of genetic structure (FST = 0.027; best fit of k = 1 with STRUCTURE) revealed no meaningful differentiation between these populations. Thus, our results indicate that the ocelot populations sampled in these fragments are still not significantly different genetically, a pattern that strongly contrasts with that previously observed in jaguars for the same comparisons. This observation is likely due to a combination of two factors: (i) larger effective population size of ocelots (relative to jaguars) in each fragment, implying a slower effect of drift-induced differentiation; and (ii) potentially some remaining permeability of the anthropogenic matrix for ocelots, as opposed to the observed lack of permeability for jaguars. The persistence of ocelot gene flow between these areas must be prioritized in long-term conservation planning on behalf of these felids. [ABSTRACT FROM AUTHOR]

Human-wildlife conflicts have grown in Brazil over the past 10 years. There has been a dramatic increase in the number, diversity of species involved, and even in the severity of outcomes. This growth is attributed to several factors: expanding human settlement, growth of outdoor recreation, and increase in the number of species that have adapted to living in human dominated landscapes. Managing these species is complicated by the growing diversity of wildlife values among different publics. We describe conflicts involving jaguars, pumas, capybaras (associated with agricultural damage, vehicle collisions, and transmission of disease) and wild boars (a spreading exotic species involving issues of hunting/antihunting). Two critical needs are identified: (a) Move from a consen'ation to a management paradigm, where there is need to reduce populations, rather than the conventional situation where the population was expected to increase and (b) Apply interdisciplinary approaches with particular attention to bringing in the social sciences. [ABSTRACT FROM AUTHOR]

The article offers information on the status of jaguar Panthera onca in Pantanal as a well preserved biome compared to other biomes in Brazil. Original vegetation cover in the Pantanal plain, it says, is at 85% while 50% of original vegetation in the Upper Paraguay watershed has been altered. Extent of occupancy (EOO) of jaguars in Pantanal is estimated at 63% and density is 7.0 jaguars for every square kilometer (sq km) area. It mentions threats to jaguars in Pantanal including fragmentation of habitat due to intensified land use, illegal hunting activities and retaliation of ranchers due to jaguars preying on cattle. It also notes regional policies for solving problems including environmental actions, tax benefits and increasing regional prices of beef.

In spite of the worldwide occurrence of domestic cats and dogs, and their close relationship with humans, the number of published papers on free-ranging cats Felis catus and dogs Canis familiaris, is small. The diet of both species was estimated in a suburban and rural environment in July 2002 and January 2003. Visual observations and scat collection of both species were accomplished along a 10 km transect line in the Campus ‘Luiz de Queiroz’, University of São Paulo, Piracicaba, south-eastern Brazil. The diet of both species was determined by analysis of sterilized, washed, dried and sorted scats. Estimated abundances of free-ranging cats and dogs in the sampled area were 81 (±4.32) and 42 (±2.96), respectively. Cats and dogs were more abundant in the suburban than in the rural environment ( t=3.78, P<0.001, N=55; t=8.38, P<0.001, N=55, respectively) and cats were more abundant than dogs in the suburban environment ( t=6.76, P<0.001, N=55), even though there was no significant difference between the abundance of both species in the rural environment ( t=0.82, P=0.46, N=55). Invertebrates were the most commonly consumed item by both species, followed by mammals (cats: 63.24 and 20.51%; dogs: 57.05 and 25.15%, respectively). Niche breadth was 0.4892 for cats and 0.4463 for dogs. Niche overlap was almost complete (0.97108). The consumption of mammals was estimated to be between 16.76 and 25.42 kg individual−1year−1 for dogs and between 2.01 and 2.9 kg individual−1year−1 for cats. These data might be useful to establish a management program to minimize the predation pressure of free-ranging cats and dogs on wildlife. [ABSTRACT FROM AUTHOR]

Discusses the findings of a study on the problems associated with the depredation of domestic livestock by jaguars and pumas in Brazil. Correlation between large cat populations and domestic animal preying; Ways to reduce the frequency of livestock depredation; Actions taken by ranchers to respond to depredation of domestic livestock.

Purpose: Standard of care for various retinal diseases involves recurrent intravitreal injections. This motivates mathematical modeling efforts to identify influential factors for ocular drug residence time, aiming to minimize administration frequency. We sought to describe the vitreal diffusion of therapeutics in nonclinical species frequently used during drug development assessments. In human eyes, we investigated the impact of variability in vitreous cavity size and eccentricity, and in injection location, on drug disposition., Methods: Using a first-passage time approach, we modeled the transport-controlled distribution of two standard therapeutic protein formats (Fab and IgG) and elimination through anterior and posterior pathways. Anatomical three-dimensional geometries of mouse, rat, rabbit, cynomolgus monkey, and human eyes were constructed using ocular images and biometry datasets. A scaling relationship was derived for comparison with experimental ocular half-lives., Results: Model simulations revealed a dependence of residence time on ocular size and injection location. Delivery to the posterior vitreous resulted in increased vitreal half-life and retinal permeation. Interindividual variability in human eyes had a significant influence on residence time (half-life range of 5-7 days), showing a strong correlation to axial length and vitreal volume. Anterior exit was the predominant route of drug elimination. Contribution of the posterior pathway displayed a 3% difference between protein formats but varied between species (10%-30%)., Conclusions: The modeling results suggest that experimental variability in ocular half-life is partially attributed to anatomical differences and injection site location. Simulations further suggest a potential role of the posterior pathway permeability in determining species differences in ocular pharmacokinetics.

Camera traps became the main observational method of a myriad of species over large areas. Data sets from camera traps can be used to describe the patterns and monitor the occupancy, abundance, and richness of wildlife, essential information for conservation in times of rapid climate and land-cover changes. Habitat loss and poaching are responsible for historical population losses of mammals in the Atlantic Forest biodiversity hotspot, especially for medium to large-sized species. Here we present a data set from camera trap surveys of medium to large-sized native mammals (>1 kg) across the Atlantic Forest. We compiled data from 5380 ground-level camera trap deployments in 3046 locations, from 2004 to 2020, resulting in 43,068 records of 58 species. These data add to existing data sets of mammals in the Atlantic Forest by including dates of camera operation needed for analyses dealing with imperfect detection. We also included, when available, information on important predictors of detection, namely the camera brand and model, use of bait, and obstruction of camera viewshed that can be measured from example pictures at each camera location. Besides its application in studies on the patterns and mechanisms behind occupancy, relative abundance, richness, and detection, the data set presented here can be used to study species' daily activity patterns, activity levels, and spatiotemporal interactions between species. Moreover, data can be used combined with other data sources in the multiple and expanding uses of integrated population modeling. An R script is available to view summaries of the data set. We expect that this data set will be used to advance the knowledge of mammal assemblages and to inform evidence-based solutions for the conservation of the Atlantic Forest. The data are not copyright restricted; please cite this paper when using the data., (© 2024 The Ecological Society of America.)

Over the past 40 years, there has been a strong focus on the development of mathematical models of angiogenesis, while developmental remodelling has received little such attention from the mathematical community. Sprouting angiogenesis can be seen as a very crude way of laying out a primitive vessel network (the raw material), while remodelling (understood as pruning of redundant vessels, diameter control, and the establishment of vessel identity and hierarchy) is the key to turning that primitive network into a functional network. This multiscale problem is of prime importance in the development of a functional vasculature. In addition, defective remodelling (either during developmental remodelling or due to a reactivation of the remodelling programme caused by an injury) is associated with a significant number of diseases. In this review, we discuss existing mathematical models of developmental remodelling and explore the important contributions that these models have made to the field of vascular development. These mathematical models are effectively used to investigate and predict vascular development and are able to reproduce experimentally observable results. Moreover, these models provide a useful means of hypothesis generation and can explain the underlying mechanisms driving the observed structural and functional network development. However, developmental vascular remodelling is still a relatively new area in mathematical biology, and many biological questions remain unanswered. In this review, we present the existing modelling paradigms and define the key challenges for the field., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Crawshaw et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Angiogenesis occurs in distinct phases: initial spouting is followed by remodelling in which endothelial cells (ECs) composing blood vessels rearrange by migrating against the direction of flow. Abnormal remodelling can result in vascular malformation. Such is the case in mutation of the Alk1 receptor within the mouse retina which disrupts flow-migration coupling, creating mixed populations of ECs polarised with/against flow which aggregate into arteriovenous malformations (AVMs). The lack of live imaging options in vivo means that the collective EC dynamics that drive AVM and the consequences of mixed populations of polarity remain a mystery. Therefore, our goal is to present a novel agent-based model to provide theoretical insight into EC force transmission and collective dynamics during angiogenic remodelling. Force transmission between neighbouring agents consists of extrusive forces which maintain spacing and cohesive forces which maintain the collective. We performed migration simulations within uniformly polarised populations (against flow) and mixed polarity (with/against flow). Within uniformly polarised populations, extrusive forces stabilised the plexus by facilitating EC intercalation which ensures that cells remained evenly distributed. Excess cohesion disrupts intercalation, resulting in aggregations of cells and functional shunting. Excess cohesion between ECs prevents them from resolving diameter balances within the plexus, leading to prolonged flow reversals which exert a critical behaviour change within the system as they switch the direction of cell migration and traffic patterns at bifurcations. Introducing mixtures of cell polarity dramatically changed the role of extrusive forces within the system. At low extrusion, opposing ECs were able to move past each other; however, at high extrusion the pushing between cells resulted in migration speeds close to zero, forming traffic jams and disrupting migration. In our study, we produced vascular malformations and functional shunting with either excess cohesion between ECs or mixtures of cell polarity. At the centre of both these mechanisms are cell-cell adherens junctions, which are involved in flow sensing/polarity and must remodelling dynamically to allow rearrangements of cells during vascular patterning. Thus, our findings implicate junctional dysfunction as a new target in the treatment and prevention of vascular disease and AVMs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Edgar, Park, Crawshaw, Osborne, Eichmann and Bernabeu.)

Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and function. 1-4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations. 5 Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range. 6-8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars' spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The field of movement ecology has rapidly grown during the last decade, with important advancements in tracking devices and analytical tools that have provided unprecedented insights into where, when, and why species move across a landscape. Although there has been an increasing emphasis on making animal movement data publicly available, there has also been a conspicuous dearth in the availability of such data on large carnivores. Globally, large predators are of conservation concern. However, due to their secretive behavior and low densities, obtaining movement data on apex predators is expensive and logistically challenging. Consequently, the relatively small sample sizes typical of large carnivore movement studies may limit insights into the ecology and behavior of these elusive predators. The aim of this initiative is to make available to the conservation-scientific community a dataset of 134,690 locations of jaguars (Panthera onca) collected from 117 individuals (54 males and 63 females) tracked by GPS technology. Individual jaguars were monitored in five different range countries representing a large portion of the species' distribution. This dataset may be used to answer a variety of ecological questions including but not limited to: improved models of connectivity from local to continental scales; the use of natural or human-modified landscapes by jaguars; movement behavior of jaguars in regions not represented in this dataset; intraspecific interactions; and predator-prey interactions. In making our dataset publicly available, we hope to motivate other research groups to do the same in the near future. Specifically, we aim to help inform a better understanding of jaguar movement ecology with applications towards effective decision making and maximizing long-term conservation efforts for this ecologically important species. There are no costs, copyright, or proprietary restrictions associated with this data set. When using this data set, please cite this article to recognize the effort involved in gathering and collating the data and the willingness of the authors to make it publicly available., (© 2018 The Authors. Ecology © 2018 The Ecological Society of America.)

Background: Non-invasive ventilation is sometimes unable to provide the respiratory needs of very premature infants in the delivery room. While airway obstruction is thought to be the main problem, the site of obstruction is unknown. We investigated whether closure of the larynx and epiglottis is a major site of airway obstruction., Methods: We used phase contrast X-ray imaging to visualise laryngeal function in spontaneously breathing premature rabbits immediately after birth and at approximately 1 hour after birth. Non-invasive respiratory support was applied via a facemask and images were analysed to determine the percentage of the time the glottis and the epiglottis were open., Hypothesis: Immediately after birth, the larynx is predominantly closed, only opening briefly during a breath, making non-invasive intermittent positive pressure ventilation (iPPV) ineffective, whereas after lung aeration, the larynx is predominantly open allowing non-invasive iPPV to ventilate the lung., Results: The larynx and epiglottis were predominantly closed (open 25.5%±1.1% and 17.1%±1.6% of the time, respectively) in pups with unaerated lungs and unstable breathing patterns immediately after birth. In contrast, the larynx and the epiglottis were mostly open (90.5%±1.9% and 72.3%±2.3% of the time, respectively) in pups with aerated lungs and stable breathing patterns irrespective of time after birth., Conclusion: Laryngeal closure impedes non-invasive iPPV at birth and may reduce the effectiveness of non-invasive respiratory support in premature infants immediately after birth., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Measures of traits are the basis of functional biological diversity. Numerous works consider mean species-level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait-based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from -5.83 to -29.75 decimal degrees of latitude and -34.82 to -56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non-volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data., (© 2018 by the Ecological Society of America.)

Antenatal glucocorticoids, exogenous surfactant, and positive end-expiratory pressure (PEEP) ventilation are commonly provided to preterm infants to enhance respiratory function after birth. It is unclear how these treatments interact to improve the transition to air-breathing at birth. We investigated the relative contribution of antenatal betamethasone, prophylactic surfactant, and PEEP (3 cmH 2 O) on functional residual capacity (FRC) and dynamic lung compliance (C DL ) in preterm (28 day GA) rabbit kittens at birth. Kittens were delivered by cesarean section and mechanically ventilated. FRC was calculated from X-ray images, and C DL was measured using plethysmography. Without betamethasone, PEEP increased FRC recruitment and C DL Surfactant did not further increase FRC, but significantly increased C DL Betamethasone abolished the benefit of PEEP on FRC, but surfactant counteracted this effect of betamethasone. These findings indicate that low PEEP levels are insufficient to establish FRC at birth following betamethasone treatment. However, surfactant reversed the effect of betamethasone and when combined, these two treatments enhanced FRC recruitment irrespective of PEEP level., (Copyright © 2016 the American Physiological Society.)