Ophiophagy by banded krait (Bungarus fasciatus) exposed by a road kill

Bungarus fasciatus (Schneider, 1801) is a nocturnal, large bodied krait species, widely distributed throughout South and Southeast Asia. It is found at a variety of habitats with relatively large home ranges. The ophiophagous diet of this venomous snake comprises a broad spectrum of prey items, even including its congener B. caeruleus. It also preys on skinks, fish, frogs, and eggs of snakes. On 16 June 2021, at 2105 h, a fresh road-kill of an adult male B. fasciatus (total length 1.46 m) was observed on a newly constructed tarmac road (width of road ~6 m) at New Khawlek (23°19'16.00"N, 92°38'36.95"E; alt. 715 m a.s.l.), Lunglei District, Mizoram, India. It seems the krait remained vulnerably exposed on the motorway while consuming a redtail pit-viper, Trimeresurus erythrurus (Cantor, 1839) (total length 48.8 cm), and was fatally run over while busy swallowing more than half of the length of its prey, most probably a few minutes prior to our arrival at the site.

Sustainable road-kill mitigation in Gladak Perak Bridge at Lumajang, Indonesia

Traffic accidents involving animals occur every year. Roadkill is a serious problem faced by the whole world, including Indonesia. Therefore, it is necessary to modify road accessories to prevent accidents, both from animals and road users. Prevention can be done in several ways, such as by installing fences or creating crossing paths, for animals. The fence can be used as a barrier between the driving lane and the animal path, where they can carry out activities such as playing without disturbing road users. Meanwhile, the making of crossing paths can be used by animals as access for animal migration. This study would like to propose a design for implementing cross-fencing mitigation at Gladak Perak Bridge at Lumajang, Indonesia. This location is an accident-prone area due to the sudden crossing of monkeys, which has been a myth in the community. Through the implementation of the installation of road dividers, it is hoped that the road design at the research site becomes wildlife friendly road and the management of traffic also meet the Indonesian design standards for inter-city roads without reducing tourism potential.

Environmental Factors Determinate Roadkill Levels of the Endemic Iberian Species, Iberian Hare (Lepus Granatensis)

Lepus granatensis is an Iberian Peninsula endemic species and one of the most important small game species. We surveyed Iberian hare-vehicle accidents in roads network in southern Spain, analysing the Mediterranean landscape, the main habitats of this species. We recorded roadkill of roads during 6-month, compared hare roadkill densities to hare hunting yields. We analyzed the spatial patterns and factors that could be influencing the hare road kill. We detected blackspots of hare road kill in areas with high landscape heterogeneity and included embankments, intersections roads and high traffic intensity. The hare roadkill ranged between 6% and 41% of the annual harvest of hares killed on neighbouring hunting estates. We therefore consider it highly relevant to take into account the hare road kill, especially in hare hunting areas, suggesting to gamekeepers and managers addressing the issue of road kill of hares. It would be necessary that hunting quotas be adjusted in territories where the additive effect of these non-natural hare mortalities converge. Results point to future directions for applied research in road ecology, which would include demographic compensation and roadkill mitigation. Our methodology could be of wide use to identify lagomorphs’ road kill blackspots by analysing environmental spatial patterns.

A Spatial Approach for Modeling Amphibian Road-Kills: Comparison of Regression Techniques

Road networks are the main source of mortality for many species. Amphibians, which are in global decline, are the most road-killed fauna group, due to their activity patterns and preferred habitats. Many different methodologies have been applied in modeling the relationship between environment and road-kills events, such as logistic regression. Here, we compared the performance of five regression techniques to relate amphibians’ road-kill frequency to environmental variables. For this, we surveyed three country roads in northern Portugal in search of road-killed amphibians. To explain the presence of road-kills, we selected a set of environmental variables important for the presence of amphibians and the occurrence of road-kills. We compared the performances of five modeling techniques: (i) generalized linear models, (ii) generalized additive models, (iii) random forest, (iv) boosted regression trees, and (v) geographically weighted regression. The boosted regression trees and geographically weighted regression techniques performed the best, with a percentage of deviance explained between 61.8% and 76.6% and between 55.3% and 66.7%, respectively. Moreover, the geographically weighted regression showed a great advantage over the other techniques, as it allows mapping local parameter coefficients as well as local model performance (pseudo-R2). The results suggest that geographically weighted regression is a useful tool for road-kill modeling, as well as to better visualize and map the spatial variability of the models.

Spatio-Temporal Patterns and Consequences of Road Kills: A Review

The development and expansion of road networks have profoundly impacted the natural landscape and various life forms. Animals are affected by these roads in a myriad of ways, none as devastating as road mortalities. This article reviews the literature on the magnitude, spatiotemporal patterns, factors, and consequences of Animal-Vehicle Collisions (AVCs) and the subsequent road kills. Furthermore, the review paper briefly outlines the relationship between roads and animals in the surrounding landscape and later examines the nature and impacts of AVCs. This article evaluates the statistics on the number of road kills and a critical analysis of the spatiotemporal patterns of these mortalities is also evaluated. Subsequently, the review paper examines current mitigation measures and the challenges impeding their success. The paper then concludes with an evaluation of geospatial tools (GIS) and other technologies used in road kill studies. The relevant findings of this paper are that, (1) factors influencing road kill patterns interact with one another; (2) AVCs have serious environmental, economic and social consequences; (3) road kill mitigation strategies suffer several challenges hindering their success; and (4) specific geospatial tools and other technologies have been utilised in assessing AVC road kill patterns. The review, therefore, recommends including overall road kill clusters of all animals in mortality surveys, increasing the spatial coverage of road kill observations, consistent surveying, sufficient research on nighttime driving distances and speed, utilising citizen science in all road mortality studies and incorporating GIS into all apps used for recording road kills. An increased sufficiency in road kill data coupled with improved technologies can enable more effective mitigation strategies to prevent AVCs.

Predicting spatial and seasonal patterns of wildlife-vehicle collisions in high-risk areas

ContextVehicle collisions with wildlife can injure or kill animals, threaten human safety, and threaten the viability of rare species. This has led to a focus in road-ecology research on identifying the key predictors of ‘road-kill’ risk, with the goal of guiding management to mitigate its impact. However, because of the complex and context-dependent nature of the causes of risk exposure, modelling road-kill data in ways that yield consistent recommendations has proven challenging.AimHere we used a novel multi-model machine-learning approach to identify the spatio-temporal predictors, such as traffic volume, road shape, surrounding vegetation and distance to human settlements, associated with road-kill risk.MethodsWe collected data on the location, identity and size of each road mortality across four seasons along eight roads in southern Tasmania – a ‘road-kill hotspot’ of management concern. We focused on three large-bodied and frequently impacted crepuscular Australian marsupial herbivore species, the rufous-bellied pademelon (Thylogale billardierii), Bennett’s wallaby (Macropus rufogriseus) and the bare-nosed wombat (Vombatus ursinus). We fit the point-location data using ‘lasso-regularization’ of a logistic generalized linear model (LL-GLM) and out-of-bag optimization of a decision-tree-based ‘random forests’ (RF) algorithm.ResultsThe RF model, with high-level feature interactions, yielded superior results to the linear additive model, with a RF classification accuracy of 84.8% for the 871 road-kill observations and a true skill statistic of 0.708, compared to 61.2% and 0.205 for the LL-GLM.ConclusionsForested areas with no roadside barrier fence along curved sections of road posed the highest risk to animals. Seasonally, the frequency of wildlife-vehicle collisions increased notably for females during oestrus, when they were more dispersive and so had a higher encounter rate with roads.ImplicationsThese findings illustrate the value of using data-driven approaches to predictive modelling, as well as offering a guide to practical management interventions that can mitigate road-related hazards.