scholarly journals Road Kill of Snakes on a Highway in an Orinoco Ecosystem: Landscape Factors and Species Traits Related to Their Mortality

2019 ◽  
Vol 12 ◽  
pp. 194008291983083 ◽  
Author(s):  
Monica Rincón-Aranguri ◽  
Nicolás Urbina-Cardona ◽  
Sandra P. Galeano ◽  
Brian C. Bock ◽  
Vivian P. Páez
Keyword(s):  
Vegetation Cover ◽  
Habitat Preferences ◽  
Species Traits ◽  
Foraging Strategy ◽  
Mitigation Measures ◽  
Ecological Group ◽  
Ecological Groups ◽  
Road Kill ◽  
The Road ◽  
Landscape Characteristics

We sampled the snake fauna in 13 landscapes along 80 km of highway and in the adjacent vegetation cover in the Colombian Llanos. We registered 119 snakes belonging to 33 species. Traffic levels significantly influenced rates of snake road kill, while adjacent vegetation cover, rainfall seasonality, and landscape structure and composition did not. We classified the species into seven ecological groups based upon foraging strategy, body length, and habitat preferences. Although most of the road-killed species had an active foraging strategy, all of the ecological groups contained some species that were killed on the highway, as well as some species that inhabited adjacent vegetation cover but that were not detected on the highway. The different ecological groups were not associated with different landscape characteristics. Six of the 13 landscapes that presented the lowest species richness of road-killed species had a different ecological group represented by each of the species documented as road kills. Thus, considering the ecological group that a species belongs to provides a complementary analytical approach that permits a fuller understanding of the ecological effects of roads on the functional role of the species in the ecosystem. We recommend focusing mitigation measures on highway sectors with the greater vehicular flow, employing both preventive measures such as posting driver advisories and installing speed radars and conducting environmental education programs to raise awareness of local drivers.

scholarly journals Habitat or matrix: which is more relevant to predict road-kill of vertebrates?

2015 ◽  
Vol 75 (4 suppl 1) ◽  
pp. 228-238 ◽  
Author(s):  
C. Bueno ◽  
C. O. M. Sousa ◽  
S. R. Freitas
Keyword(s):  
Regression Models ◽  
Movement Ecology ◽  
Information Criterion ◽  
Mitigation Measures ◽  
Conservation Strategies ◽  
Southeastern Brazil ◽  
Logistic Regression Models ◽  
Road Kill ◽  
Landscape Characteristics ◽  
Effect Model

Abstract We believe that in tropics we need a community approach to evaluate road impacts on wildlife, and thus, suggest mitigation measures for groups of species instead a focal-species approach. Understanding which landscape characteristics indicate road-kill events may also provide models that can be applied in other regions. We intend to evaluate if habitat or matrix is more relevant to predict road-kill events for a group of species. Our hypothesis is: more permeable matrix is the most relevant factor to explain road-kill events. To test this hypothesis, we chose vertebrates as the studied assemblage and a highway crossing in an Atlantic Forest region in southeastern Brazil as the study site. Logistic regression models were designed using presence/absence of road-kill events as dependent variables and landscape characteristics as independent variables, which were selected by Akaike’s Information Criterion. We considered a set of candidate models containing four types of simple regression models: Habitat effect model; Matrix types effect models; Highway effect model; and, Reference models (intercept and buffer distance). Almost three hundred road-kills and 70 species were recorded. River proximity and herbaceous vegetation cover, both matrix effect models, were associated to most road-killed vertebrate groups. Matrix was more relevant than habitat to predict road-kill of vertebrates. The association between river proximity and road-kill indicates that rivers may be a preferential route for most species. We discuss multi-species mitigation measures and implications to movement ecology and conservation strategies.

scholarly journals Mass displacement of Korean clawed salamanders (Onychodactylus koreanus) and the threat of road-kill

2020 ◽  
pp. 28-31
Author(s):  
Yucheol Shin
Keyword(s):  
Hind Limb ◽  
Mass Movement ◽  
Mitigation Measures ◽  
Life History Stage ◽  
Reproductive Condition ◽  
Migration Patterns ◽  
Road Kill ◽  
The Road ◽  
Mass Displacement ◽  
The Republic

Little is known about the ecology of the Korean clawed salamander (Onychodactylus koreanus) but populations are declining due to human activities. We surveyed a mountainside road in the Republic of Korea and recorded the sex and life history stage of the salamanders crossing the road. Our results present the first evidence of mass movement in this species. We also show that road-kill is greater than estimated in previous studies. The males observed had fleshy hind-limb extensions and all females except one were gravid, indicating they were in reproductive condition and that mass movement of this species is probably linked to seasonal conditions and reproduction. Consequently, we argue that road kill may have a large impact on this species by eliminating reproductive adults. We call for road-kill mitigation measures on mountainside roads and further research into the migration patterns of this species.

Application of a combined and automated monitoring and early warning system for debris flows at the Dawinbach

2021 ◽  
Author(s):  
Tobias Schöffl ◽  
Richard Koschuch ◽  
Philipp Jocham ◽  
Johannes Hübl
Keyword(s):  
Debris Flow ◽  
Early Warning ◽  
Pulse Compression ◽  
Mitigation Measures ◽  
Heavy Rainfall Event ◽  
Monitoring Site ◽  
Traffic Lights ◽  
The Road ◽  
Pulse Compression Radar ◽  
Monitoring And Early Warning

<p>After a heavy rainfall event on August 31<sup>st</sup>, 2019, a debris flow at the Dawinbach in the municipality of Strengen (Tyrol, Austria) caused a blockage of the culvert below the provincial road B-316 and deposition in the residential area. The debris deposition raised up to 2 to 3 meters on the road and led to property damage to real estate. The total volume of the debris flow was approximately 15 000 cubic meters.</p><p>In order to control a further debris flow of this magnitude, the Austrian Service of Torrent and Avalanche Control started to construct mitigation measures. They include a channel relocation in order to significantly increase the channel crosssection. Hence the construction company STRABAG is also relocating the provincial road bridge.</p><p>Since the risk for this road section and for the workers on site is particularly high during the construction period, a combined monitoring and early warning concept was developed and implemented by the BOKU, Vienna and the company IBTP Koschuch.</p><p>The monitoring site consisting of a pulse compression radar and a pull rope system was installed 800m upstream from the fan. The combination of the two sensors now results in three major advantages.</p><ul><li>At sensor level, the system operates redundantly.</li> <li>A more reliable differentiation between increased discharge or debris flow is given.</li> <li>In the event of a false alarm, the system provides easier diagnosis and assignment of the fault.</li> </ul><p>Two events of increased runoff occurred during the deployment period. Both were successfully detected by the pulse compression radar. Here, the first event was used for threshold validation of the radar unit. Thus, an alarm could already be sent out automatically for the second one. The road is controlled by an integrated light signal system consisting of three traffic lights. A siren near the construction site can warn workers of an impending event by means of an acoustic signal. The reaction time after the alarm has been triggered is between 75 and 150 seconds, depending on the speed of the debris flow. The responsible authorities are informed by sending an SMS chain, which includes details about the type of process and the type of the activated triggering system.</p>

scholarly journals Ornithocenosis Structure in Fresh and Wet Sudubravas of Kyiv Polissya during the Breeding Period

2016 ◽  
Vol 50 (3) ◽  
pp. 241-250
Author(s):  
A. V. Plyha
Keyword(s):  
Population Density ◽  
Age Groups ◽  
Bird Species ◽  
Pine Forests ◽  
Breeding Period ◽  
Ecological Group ◽  
Ecological Groups ◽  
Age Group ◽  
Majority Population ◽  
Species Lists

Abstract This research was carried out in Kyiv Polissya geobotanical province, in one of most common woods type - fresh and wet sudubravas. Its purpose is to determine ornithocenosis structure in different age groups of this type of forest. To achieve that, forest bird species lists were composed, their population density and that of ecological groups of birds were calculated. In the course of the research in the breeding periods of 2013-2014, two-time surveys were carried out on 12 survey routes of total length 33 km. For further analysis, forests were divided into age groups: 0-20 years, 20-40 years, 40-60 years, 60-80 years, 80-100 years and forests over 100 years. Altogether 53 bird species were found. Species lists were poorest in the forests of 0-20 years (18 species), and richest in the forests over 100 years (39 species). Minimal population density was 473 individuals per square kilometer in the youngest forest age group of 0-20 years, maximal - 2155 individuals per square kilometer in pine forests aged over 100 years. Analysis of different population densities of ecological groups reveals steadily growing numbers of hollow-nesting birds and tree-nesting birds in accordance with aging of the forests. In older forests hollow-nesting birds constitute an absolute majority. Population density of another ecological group shows no such direct tendency.

Evolutionary Modeling of Routes: The Case of Road Design

2001 ◽  
Author(s):  
Ângela Guimarães Pereira
Keyword(s):  
Genetic Algorithms ◽  
Physical Space ◽  
Linear Structure ◽  
Search Space ◽  
Evaluation Methodology ◽  
Mitigation Measures ◽  
Evolutionary Modeling ◽  
Technical Parameters ◽  
The Road ◽  
Road Design

In this study a route is defined as the path that a linear structure or facility follows in the terrain. Linear structures comprise facilities such as roads, motorways, railways, pipelines, electrical power lines, and telephone cables, each of these structures requiring specific technical parameters in what concerns the geometry of the path and having different effects on the terrain they traverse. Amongst these structures, roads and motorways are the group that creates the greatest overall impact; accordingly Portuguese legislation requires an environmental impact assessment (EIA) process as part of the necessary licensing approval. Usually the alternative (or alternatives) that undergo the EIA process is justified in terms of technical and economical issues. The result is that if major environmental impacts are identified by the EIA study, a myriad of mitigation measures are proposed, very seldom the redesign of the path being carried out (Guimarães Pereira & Antunes, 1996). Preliminary studies that precede the implementation of these types of projects are technically detailed and often come together with economical feasibility studies, shelving environmental issues for later assessment. In the methodology proposed in this chapter a multidimensional evaluation methodology, multicriteria evaluation, will be combined with the robustness of a search methodology, genetic algorithms (GAs) to generate alternative road routes that take into consideration environmental, economical, technical, and social criteria. These criteria are referenced to the physical space where the road is to be placed and therefore this methodology is embedded into a geographic information system (GIS). Genetic algorithms are particularly attractive to apply to multi-modal problems, allowing the exploration of spatial features to eventually find “best compromise” alternatives because these algorithms proceed their search by maintaining a population of solutions, that they can simultaneously exploit for their efficiency.1 Moreover, the particular mixing mechanism provides the means to recombine solutions and explore the search space. The remainder of this chapter describes evolutionary modeling of road routes, in particular the coding onto a GA of the geometric algorithm that accounts for the technical aspects of motorway siting. The details of the implementation of the MCDA-GA methodology, running within the GIS GRASS 4.1 (Geographic Resources Analysis Support System) and its application to generate and evaluate alternative routes of a section of a Portuguese complementary itinerary (IC7) will be presented.

Timing of the evening emergence of Hilgendorf’s tube-nosed bat (Murina hilgendorfi) in relation to roost type and season

2020 ◽  
pp. 1-11
Author(s):  
Hayato Takada
Keyword(s):  
Predation Risk ◽  
Vegetation Cover ◽  
Growth Stage ◽  
Outer Wall ◽  
First Record ◽  
Foraging Strategy ◽  
Late Spring ◽  
Reproductive Status ◽  
Central Japan ◽  
Behavioral Aspect

Abstract Like for many species, the timing of evening emergence of bats is an important behavioral aspect that affects their fitness and has been studied in various bat species. However, little is known about emergence timing of solitary bats that frequently switch day roosts, because they are difficult to observe. In this study, I examined the emergence timing of Hilgendorf’s tube-nosed bats (Murina hilgendorfi), which are solitary and frequently switch roosts, in relation to roost type and season over six years in Hayakawa, central Japan. The results show that the bats emerged after dusk when the light was weak. Later emergence may be related to the habits of this species, such as their solitary lifestyle, slow flight speed, and gleaning foraging strategy, which may enhance predation risk. Individuals roosting in dead foliage and on the outer wall of a building situated in closed forests emerged significantly earlier than those roosting in an old mine and tunnel located in open environments, suggesting that vegetation cover and/or lower predictability of roost location provide security for bats. Bats emerged progressively earlier from late spring (preparturition) to early autumn (late lactation or post-lactation), suggesting that the reproductive status of females or the growth stage of pups may influence emergence timing. To my knowledge, this study provides the first record of the emergence timing of Hilgendorf’s tube-nosed bat, and suggests that predation risk may impact the bats’ emergence behavior.

Road and traffic factors correlated to wildlife–vehicle collisions in Galicia (Spain)

2015 ◽  
Vol 42 (1) ◽  
pp. 25 ◽  
Author(s):  
Enrique Valero ◽  
Juan Picos ◽  
Laura Lagos ◽  
Xana Álvarez
Keyword(s):  
Roe Deer ◽  
Multiple Logistic Regression Analysis ◽  
Hierarchical Cluster ◽  
Mitigation Measures ◽  
Curvature Radius ◽  
Nearest Neighbour ◽  
Continuous Variables ◽  
Hotspot Analysis ◽  
Vehicle Collisions ◽  
The Road

Context Wildlife–vehicle collisions (WVC) are one of the major risk factors for the safety of drivers, as well as a great danger to wildlife that moves through the territory. In recent decades, given the growth of these accidents, some researches emerged to understand what are the main causes of this phenomenon and find the best solutions for implementation and try to solve this problem. Aims The aim of the present study was to analyse the road and traffic characteristics of road segments with a high occurrence of WVC in north-western Spain, specifically, the collisions with wild ungulates (roe deer and wild boar). Methods A nearest-neighbour analysis was used to analyse the spatial distribution of the WVC spots, and so as to identify these hotspots of accidents, we performed a hotspot analysis using the routine nearest-neighbour hierarchical cluster. Then, we calculated the WVC density of each road segment (KP). The existence of differences in the values of variables between high and low accident densities was analysed using a Mann–Whitney U-test for the continuous variables, and a χ2-test for the categorical ones. Then, multiple logistic regression analysis was used to identify which variables could predict the existence of KPs with a high density of WVC. Key results Our results showed that the daily traffic volume, the width of the road, the number of lanes and speed limit affect whether a particular road marker has a high or low density of WVC. Conclusions We conclude that high WVC is frequently characterised by wider lanes and shoulders, as well as gentler slopes, whereas in the sections with narrower roads and a shorter curvature radius, there are some conditions (low visibility and speed reduction) that reduce the probability of having an accident with ungulates. However, the speed at which it is possible to drive on a given road section is closely related to the occurrence of WVC. Implications These findings emphasise the importance of including mitigation measures in the decision-making when planning and designing infrastructure.

Factors affecting the mortality of Lumholtz's tree-kangaroo (Dendrolagus lumholtzi) by vehicle strike

2018 ◽  
Vol 45 (6) ◽  
pp. 559 ◽  
Author(s):  
Amy L. Shima ◽  
David S. Gillieson ◽  
Gabriel M. Crowley ◽  
Ross G. Dwyer ◽  
Lee Berger
Keyword(s):  
Wildlife Habitat ◽  
Warning Signs ◽  
Mitigation Strategies ◽  
Mitigation Measures ◽  
Speed Limits ◽  
Road Kill ◽  
Male Tree ◽  
Eastern Australia ◽  
Traffic Volumes ◽  
Dendrolagus Lumholtzi

Context Vehicle strike is a major issue where wildlife habitat is intersected by busy roads. Near Threatened Lumholtz’s tree-kangaroo (Dendrolagus lumholtzi) is a large (5–10 kg) semi-arboreal mammal found in populated rural and forested areas of north-eastern Australia. Warning signs, rope bridges and underpasses have not prevented ~20 animals being killed on the road each year. Aims To identify factors influencing Lumholtz’s tree-kangaroo vehicle strike to help inform mitigation options. Methods Citizen sightings (1998–2000) and 90 road-kills collected over 4.5 years on the Atherton Tablelands, Australia, were examined to determine the causes of vehicle strike in Lumholtz’s tree-kangaroo. The spatial distributions of sightings and road-kills were characterised using nearest-neighbour analysis, and the relationship between them was determined using a Bayesian approach that accounted for spatial autocorrelation. Gender, age, weight, season, rainfall, road and verge characteristics, traffic volumes, speed limits and mitigation measures were recorded to assess their influence on road-kill risk. Adequacy of speed limits to prevent collisions along road sections with more than four road-kills per 8 km (hazard zones) was assessed from visibility and stopping distances. Key results Vehicle strikes mainly affected male tree-kangaroos (2–5 years, 5.5–8 kg), occurred where live animals were most frequently sighted and were most likely on roads with narrow verges, low visibility and medium traffic volumes. Speed limits at hazard zones were inadequate to prevent collisions. Few warning signs corresponded with these zones, and road mortalities persisted where they did. Conclusions Unpredictable dispersal of young males and vehicle speeds unsuited to road conditions drive road mortalities in Lumholtz’s tree-kangaroo. Because tree-kangaroos do not appear to respond to existing mitigation measures, reducing traffic speeds, and increasing visibility, appear to be the most effective mitigation strategies for reducing tree-kangaroo road mortality. Implications Our findings suggest that tree-kangaroo road-kill can be reduced by reducing speed limits in line with government recommendations and increasing visibility by clearing road verges along sections of road with the highest tree-kangaroo mortality. Warning signage should be re-evaluated to determine whether its effectiveness can be improved.

scholarly journals Soils and earthworms as a final chapter in the narrative of a steelworks

2020 ◽  
Vol 27 (2) ◽  
pp. 39-48
Author(s):  
K.R Butt ◽  
S.M Quigg
Keyword(s):  
Sewage Sludge ◽  
Vegetation Cover ◽  
Water Infiltration ◽  
Ecological Groups ◽  
Short Rotation ◽  
Density And Biomass ◽  
Reclaimed Soils ◽  
Planted Tree ◽  
Salix Spp

Hallside steelworks, South Lanarkshire, Scotland, employed thousands of people and constructed rails and ships for over a century, before this successful industry closed in the 1970s. The site,south-east of Glasgow, was then reclaimed from dereliction during the 1990s to produce biomass through Short Rotation Coppice (SRC) of willow trees (Salix spp.). On site, the contaminated soil was removed, and a rudimentary substrate created with a mixture of sewage sludge and colliery spoil, the latter moved from nearby tips to release land for housing. Trees were planted and earthworms (Annelida) added to potentially assist growth. Initially recognised as a flagship for reclamation, the site was then abandoned. In 2018, information was gathered on the development of soils and on earthworm communities. This was achieved by sampling across the 35 ha site below willow, other planted tree species and grassland. The results showed that reclaimed soils were very stony, compacted, resistant to water infiltration but relatively uncontaminated. Willow had grown, but coppicing had not occurred. Earthworm introduction was initially unsuccessful, but colonisation took place from adjacent unadulterated areas and 16 species from three ecological groups were recorded. Mean community density was 208 ± 18.1 earthworms m-2 with a mean mass of 71 ± 6.1 g m-2. Type of vegetation cover had a significant (P <0.05) effect on community density and biomass. The site is now used for recreation and is an effective greenspace close to Glasgow.

scholarly journals Butterfly biodiversity in the city is driven by the interaction of the urban landscape and species traits: a call for contextualised management

2021 ◽  
Author(s):  
Clàudia Pla-Narbona ◽  
Constantí Stefanescu ◽  
Joan Pino ◽  
Francisco J. Cabrero-Sañudo ◽  
Enrique García-Barros ◽  
...  
Keyword(s):  
Species Richness ◽  
Functional Groups ◽  
Urban Landscape ◽  
Landscape Planning ◽  
Choice Model ◽  
Species Traits ◽  
Similar Species ◽  
Landscape Characteristics ◽  
Mobile Species ◽  
The City

Abstract Context Urbanisation is an environmental filter for many species that leads to community homogenisation, with a few species inhabiting isolated patches (e.g. public and private gardens and parks) embedded within the urban landscape. Promoting biodiversity in urban areas requires understanding which species traits allow species to survive the urban landscape. Objectives The objective of this study was to assess how species traits and landscape factors combine to allow species functional groups to live in the city. Methods We used butterfly count data collected by volunteers in 24 gardens of Barcelona city, during 2018 and 2019. Species were clustered in functional groups according to their traits. We applied a multinomial choice model to test for the effect of the landscape on the different functional groups. Results Three functional groups became prevalent in the city while a fourth, containing most sedentary specialist species, was filtered out. Although the observed groups had similar species richness, abundances varied depending on urban landscape characteristics. Specialist sedentary specialists and medium mobile species were all favoured by patch connectivity; while the presence of mobile generalist species was only enhanced by habitat quality. Our results indicate that butterfly communities are more diverse in highly connected gardens. Conclusions Our study highlights the need of contextualised management with actions accounting for the species functional groups, rather than a management focused on general species richness. It demonstrates that urban landscape planning must focus on improving connectivity inside the city in order to diversify the community composition.

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