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The greatest driver of the current biodiversity crisis is habitat loss. Roads are a major contributor to habitat loss because they destroy and fragment habitat, in addition to causing direct mortality. Animals may respond to roads either by avoiding them, thus leading to population isolation, or by attempting to cross them, thus potentially leading to increased mortality and, if so, also to population isolation. We studied the impact of road density on abundance of two snake species: redbelly snakes (Storeria occipitomaculata Storer, 1839) and garter snakes (Thamnophis sirtalis Linnaeus, 1758) around Ottawa, Canada. We hypothesized that roads are detrimental to snake populations due to road avoidance and mortality. Therefore, we predicted that snakes should be less abundant at sites with higher road density in their surroundings. We deployed cover boards at 28 sites along a gradient of road density in 2020 and 2021. We visited sites weekly, counted the number of individuals of both species, and measured snout-vent length (SVL) of all individuals captured. We captured fewer garter snakes at sites surrounded by more roads and fewer redbelly snakes at sites surrounded by more urban habitat. Snakes at sites surrounded by more roads were not smaller. The effects of roads and urbanization on the number of snakes were modest, but indicate decreasing population sizes that could lead to loss of ecological function. Key words: anthropogenic land use, road ecology, garter snake, Thamnophis sirtalis, redbelly snake, Storeria occipitomaculata, 1 Introduction The greatest driver of global biodiversity loss is anthropogenic land use (Pimm and Raven 2000; Sala et al. 2000; Thomas et al. 2004; Didham et al. 2005; Valiente-Banuet [...]

As the global population increases, the expansion of road networks has led to the destruction and disturbance of terrestrial and aquatic habitats. Road-related stressors have significant effects on both lotic and lentic habitats. While there are several systematic reviews that evaluate the effects of roads on lotic environments, there are none that consider their effects on lentic habitats only. We conducted a literature review to achieve two objectives: (1) to summarize the effects of roads on the physical, chemical, and biological properties of lentic environments; and (2) to identify biases and gaps in our current knowledge of the effects of roads on lentic habitats, so that we could find promising areas for future research. Our review found 172 papers published between 1970 and 2020. The most frequently studied stressors associated with roads included road salt and heavy metal contamination (67 and 43 papers, respectively), habitat fragmentation (37 papers), and landscape change (14 papers). These stressors can lead to alterations in conductivity and chloride levels, changes in lake stratification patterns, increases in heavy metal concentrations in water and organisms, and significant mortality as amphibians disperse across roadways. We also identified a variety of other stressors that may be understudied based on their frequency of appearance in our search results, including polycyclic aromatic hydrocarbons, road dust, increased accessibility, hydrological changes, noise pollution, dust suppressants, sedimentation, invasive species introductions, and water withdrawal. Our review indicated that there are strong geographic biases in published studies, with 57.0% examining North American sites and 30.2% examining European sites. Furthermore, there were taxonomic biases in the published literature, with most studies focusing on amphibians (41.7%), fish (15.6%), and macroinvertebrates (14.6%), while few considered zooplankton (8.3%), diatoms (7.3%), amoebas (5.2%), water birds (3.1%), reptiles (2.1%), and macrophytes (1.0%). Based on our review, we have identified promising areas for future research for each of the major stressors related to roadways. However, we speculate that rectifying the geographic and taxonomic bias of our current knowledge could significantly advance our understanding of the impacts of roads on lentic environments, thereby better informing environmental management of these important habitats. Key words: lakes, ponds, roads, lentic, habitat, anthropogenic stress Avec l'augmentation de la population mondiale, l'expansion des reseaux routiers a entraine la destruction et la perturbation des habitats terrestres et aquatiques. Les facteurs de stress lies aux routes ont des effets importants sur les habitats lotiques et lentiques. Alors que plusieurs revues systematiques evaluent les effets des routes sur les environnements lotiques, aucune ne considere leurs effets sur les habitats lentiques uniquement. Les auteurs ont effectue une revue de la litterature pour atteindre deux objectifs : (1) resumer les effets des routes sur les proprietes physiques, chimiques et biologiques des milieux lentiques; et (2) identifier les biais et les lacunes des connaissances actuelles quant aux effets des routes sur les habitats lentiques afin de trouver des domaines prometteurs pour les recherches futures. Leur examen a permis de repertorier 172 articles publies entre 1970 et 2020. Les facteurs de stress associes aux routes les plus frequemment etudies sont le sel de deneigement et la contamination par les metaux lourds (67 et 43 articles respectivement), la fragmentation de l'habitat (37 articles) et la modification du paysage (14 articles). Ces facteurs de stress peuvent entrainer des modifications de la conductivite et des niveaux de chlorure, des changements dans les patrons de stratification des lacs, des augmentations des concentrations de metaux lourds dans l'eau et les organismes, et une mortalite significative lorsque les amphibiens se dispersent sur les routes. Ils ont egalement identifie une variete d'autres facteurs de stress qui peuvent etre sous-etudies en fonction de leur frequence d'apparition dans leurs resultats de recherche, notamment les hydrocarbures aromatiques polycycliques, la poussiere des routes, l'accessibilite accrue, les changements hydrologiques, la pollution sonore, les depoussierants, la sedimentation, l'introduction d'especes envahissantes et le retrait de l'eau. Leur examen a indique qu'il existe de forts biais geographiques dans les etudes publiees, 57,0 % d'entre elles portant sur des sites nord-americains et 30,2 % sur des sites europeens. De plus, il existe des biais taxonomiques dans la litterature publiee, la plupart des etudes se concentrant sur les amphibiens (41,7 %), les poissons (15,6 %) et les macroinvertebres (14,6 %), tandis que peu d'entre elles consideraient le zooplancton (8,3 %), les diatomees (7,3 %), les amibes (5,2 %), les oiseaux aquatiques (3,1 %), les reptiles (2,1 %) et les macrophytes (1,0 %). Sur la base de cet examen, ils ont identifle des domaines prometteurs pour la recherche future pour chacun des principaux facteurs de stress lies aux routes. Cependant, ils supposent que la rectification des biais geographiques et taxonomiques des connaissances actuelles pourrait faire progresser de maniere significative notre comprehension des impacts des routes sur les environnements lentiques, et ainsi mieux eclairer les decision en matiere de gestion environnementale de ces habitats importants. [Traduit par la Redaction] Mots-cles : lacs, etangs, routes, lentique, habitat, stress anthropique, 1 Introduction The Earth currently contains over 21 million km of roads, and models predict that several million more km will be constructed by the year 2050 (Meijer et al. [...]

A change in the driver's vision quality might result in deterioration of their perception and effectiveness. The lack of an integrated algorithm to distinguish the location of driver vision impairment motivated this study. The proposed model benefits from a combination of several sub-algorithms such as sun positioning, glare detection, and contrasting shadow illustrator derived from raw geospatial data. The methodology is implemented through a case study involving a road network in a large metropolitan area, a digital elevation model, the associated hillshade geographic data, and weather data from Montreal, Canada. The methodology and corresponding data analysis were implemented in Python. The results revealed a geospatial model to estimate the boundaries of transition points between the glare and contrasting shadows created by changes in the roadway surroundings. The results provided by the model can be used as a tool to aid decisionmakers in new road construction and urban planning by creating safety countermeasure strategies and design review of road geometry. Key words: sun glare, contrasting shadow, geospatial data processing, road environment mapping. Un changement au niveau de la qualite de vision des conducteurs pourrait entrainer une deterioration de leur perception et de leur efficacite. L'absence d'un algorithme integre pour discerner l'emplacement ou se produit la deficience visuelle des conducteurs motive cette etude. Le modele propose beneficie d'une combinaison de plusieurs sous-algorithmes, tels que le positionnement du soleil, la detection de la reflexion du soleil et l'illustrateur d'ombres contrastantes derive de donnees geospatiales brutes. La methodologie est mise en reuvre au moyen d'une etude de cas portant sur un reseau routier metropolitain de grande taille, un modele altimetrique numerique, les donnees geographiques connexes sur l'ombrage des collines et les donnees meteorologiques de Montreal, au Canada. La methodologie et l'analyse des donnees correspondantes sont effectuees en Python. Le resultat a revele un modele geospatial pour estimer les limites des points de transition entre la reflexion et les ombres contrastantes creees par les changements dans l'environnement routier. Les resultats fournis par le modele peuvent etre utilises comme un outil pour aider les decideurs dans la construction de nouvelles routes et la planification urbaine en creant des strategies de contre-mesures de securite et la revision de la conception de la geometrie routiere. [Traduit par la Redaction] Mots-cles : reflexion du soleil, ombre contrastante, traitement des donnees geospatiales, modelisation de l'environnement routier., Introduction Road environment and driving perception are hidden tips for queue forming and safety degradation. The shining of direct sunlight in the driver's eye affects the driving perception. This has [...]

This paper proposes a real-time winter road surface condition (RSC) monitoring solution that automatically generates descriptive RSC information in terms of snow and ice coverage by using images from fixed traffic and weather cameras. Several state-of-the-art pre-trained deep neural networks are customized and fine-tuned to address a specific domain, classifying the amount of snow coverage on a road surface. A thorough evaluation is conducted to identify and select the best model. This evaluation uses an extensive set of experiments to test the accuracy and generalization of each model and uses transfer-learning to fine-tune each of the pre-trained models on independent images from different traffic and weather cameras. The transferability of each model, relationship between model performance and data size, and the system settings of each model are then examined. Lastly, three online weight calibration methods are proposed to automatically update the model in new environments. The result shows that re-training the model using images from a mixed set of cameras has the most promising results. Key words: road surface condition, realtime recognition, deep learning, convolutional neural network. Dans ce document, on propose une solution de surveillance en temps reel de l'etat de la surface de roulement (ESR) en hiver qui genere automatiquement des informations descriptives de l'ESR en matiere de couverture de neige et glace en utilisant des images de cameras fixes de circulation et meteo. Plusieurs reseaux de neurones profonds preentraines de pointe sont adaptes et peaufines pour traiter un domaine specifique, soit celui de classifier la quantite de couverture de neige sur une surface de roulement. Une evaluation approfondie est effectuee afin de determiner et de choisir le meilleur modele. Cette evaluation utilise un vaste ensemble d'experiences pour verifier la precision et la generalisation de chaque modele et utilise l'apprentissage par transfert pour peaufiner chacun des modeles pre-entraines sur des images independantes provenant de differentes cameras de circulation et meteo. La transferabilite de chaque modele, la relation entre la performance du modele et la taille des donnees ainsi que les parametres du systeme de chaque modele sont ensuite examines. Enfin, trois methodes de calibration de poids en ligne sont proposees pour mettre a jour automatiquement le modele dans de nouveaux environnements. Le resultat montre que le reentrainement du modele a l'aide d'images provenant d'un ensemble de cameras fournit les resultats les plus prometteurs. [Traduit par la Redaction] Mots-cles: etat de la surface de roulement, reconnaissance en temps reel, apprentissage profond, reseau neuronal convolutif., 1. Introduction In countries with severe winter seasons such as Canada, road surface conditions (RSC) on highways during snow events could vary remarkably from location to location and over time. [...]

Anthropogenic disturbances, including roads, are known to influence animal habitat selection and mortality. In this study, we consider the role of sensory perception in understanding why and how animals respond to disturbances. Our goal was to investigate the effect of visual perception (visibility) around roads on grizzly bear (Ursus arctos horribilis Ord, 1815) habitat selection and mortality in Alberta, Canada. We used detailed topographic and vegetation data from airborne light detection and ranging (lidar) to estimate visibility around roads. We modelled habitat selection as a function of road visibility and environmental variables using GPS telemetry data from 39 grizzly bears and integrated step selection analysis (iSSA). Finally, we assessed mortality risk in visible areas by comparing habitat selection between grizzly bears that died and those that survived. We found that grizzly bears were less likely to select visible areas when moving slowly or resting, but were more likely to select visible areas when travelling. We found that grizzly bears that survived selected for areas farther from roads than grizzly bears that died. However, no difference in selection for visible areas was observed. An exploratory analysis showed that grizzly bear mortalities commonly occurred in visible areas. Our findings highlight the importance of sensory perception in understanding animal behaviour. Key words: anthropogenic disturbance, grizzly bears, habitat selection, integrated step selection analysis, perception, road ecology, Ursus arctos horribilis, visibility. Il est bien etabli que les perturbations d'origine humaine, y compris les routes, influencent la selection d'habitats par les animaux et la mortalite de ces derniers. Nous examinons le role de la perception sensorielle pour comprendre pourquoi et comment les animaux reagissent a des perturbations. L'objectif est d'etudier l'effet de la perception visuelle (la visibilite) autour des routes sur la selection d'habitats et la mortalite de grizzlis (Ursus arctos horribilis Ord, 1815) en Alberta (Canada). Nous utilisons des donnees topographiques et de vegetation detaillees de detection et telemetrie par ondes lumi-neuses (lidar) aeroportees pour estimer la visibilite autour de routes. Nous modelisons la selection d'habitats comme etant une fonction de la visibilite autour des routes et de variables environnementales en utilisant des donnees de telemetrie GPS pour 39 grizzlis et l'analyse de selection de pas integree (iSSA). Enfin, nous evaluons le risque de mortalite dans les secteurs visibles en comparant la selection d'habitats des grizzlis qui meurent et a celle des grizzlis qui survivent. Nous constatons que les grizzlis sont moins susceptibles de choisir des secteurs visibles quand ils se deplacent lentement ou sont au repos, mais plus susceptibles de choisir des secteurs visibles quand ils se deplacent entre differents lieux. Nous constatons que les grizzlis qui survivent choisissent des secteurs plus eloignes de routes que les grizzlis qui meurent. Aucune difference n'est toutefois observee en ce qui concerne la selection de secteurs visibles. Une analyse exploratoire montre que les morts de grizzlis se produisent souvent dans des secteurs visibles. Nos constatations soulignent l'importance de tenir compte de la perception sensorielle pour comprendre les comportements d'animaux. [Traduit par la Redaction] Mots-cles : perturbation d'origine humaine, grizzlis, selection d'habitats, analyse de selection de pas integree, perception, ecologie des routes, Ursus arctos horribilis, visibilite., Introduction The study of animal behaviour is incomplete without considering the overarching effects of human activity. Few wildlife populations are untouched by human activity. In particular, roads are considered the [...]

Coastal erosion can be a serious issue requiring accurate observations in order to evaluate vulnerable areas and determine the subsequent actions to address this problem. The Town of Bay Bulls, [...]

Roads and their associated low-frequency noise have been linked with a reduction in abundance and density for many songbird species. However, a handful of species remain equally abundant in roadside habitats and nondisturbed areas. Abundance is a valuable baseline indicator of a species' ability to adapt to habitats altered by roads, but does not directly ascertain whether health is affected in these species. Here we examine whether Black-capped Chickadees (Poecile atricapillus (L., 1766)), a species that remains abundant near roads, exhibit higher levels of chronic stress or reduced physical condition when residing near roads. Neither hematological measures of chronic stress, nor any of our measures of physical condition, differed significantly between Black-capped Chickadees inhabiting areas near or far from roads. Our results suggest that health and physical condition, like abundance, are not significantly affected by roads in the Black-capped Chickadee. This species may be an ideal model for understanding how some songbird species adapt to roads and the noise that they produce. Key words: bird, health, stress, noise, distance, road, Black-capped Chickadee, Poecile atricapillus. Des liens ont ete etablis entre les routes et les bruits de basses frequences qui leur sont associes, et une diminution de l'abondance et de la densite de nombreuses especes d'oiseaux chanteurs. Quelques especes demeurent toutefois tout aussi abondantes dans des habitats de bord de route que dans les zones non perturbees. Si l'abondance est un indicateur de base utile de la capacite d'une espece a s'adapter a des habitats modifies par des routes, elle ne permet pas d'etablir directement si la sante de cette espece est affectee. Nous avons verifie si les mesanges a tete noire (Poecile atricapillus (L., 1766)), une espece qui demeure abondante a proximite des routes, presentent des niveaux de stress chronique plus eleves ou un etat physique diminue quand elles resident pres de routes. Aucune difference significative n'a ete observee dans les mesures hematologiques du stress chronique, ni dans aucune mesure de l'etat physique, entre les mesanges a tete noire habitant des zones a proximite de routes et celles habitant des zones eloignees des routes. Nos resultats indiqueraient que la sante et l'etat physique des mesanges a tete noire, comme leur abondance, ne sont pas influences de maniere significative par les routes. Cette espece pourrait constituer un modele ideal pour comprendre comment certaines especes d'oiseaux chanteurs s'adaptent aux routes et aux bruits qu'elles engendrent. [Traduit par la Redaction] Mots-cles: oiseau, sante, stress, bruit, distance, route, mesange a tete noire, Poecile atricapillus., Introduction Urbanization has been associated with declines in the abundance and diversity of many songbird species (Beissinger and Osborne 1982). Factors contributing to these declines include reduced habitat (Friesen et [...]